ADM Traffic Control Devices Manual 0-1_2004R

Version 0.1, 2004

TRAFFIC CONTROL DEVICES MANUAL

PREFACE TO VERSION 0.1 OF THIS MANUAL The Abu Dhabi Traffic Control Devices Manual has been developed by the Abu Dhabi Municipality Road Department to provide guidance to consultants and contractors working on Department projects in the greater Abu Dhabi metropolitan area. To help ensure the conformity of traffic control devices within the UAE, this manual is based chiefly on the equivalent Dubai manual. Where appropriate, this manual also incorporates standards from the draft Gulf Cooperation Council traffic control devices manual and the Road Department's Standard Drawings.

Version 0.0, Interim Edition


Table of Contents

Page No.

CHAPTER 1: GENERAL PROVISIONS 1.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1 1.1.1 REQUIREMENTS AND PURPOSE OF TRAFFIC CONTROL DEVICES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1 1.1.2 STANDARDIZATION OF APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . .1-1 1.1.3 APPROVAL FOR PLACEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2 1.1.4 EXCESSIVE USE OF TRAFFIC CONTROL DEVICES . . . . . . . . . . . . . .1-2 1.1.5 ADVERTISING SIGNING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2 1.2 CLASSIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2 1.2.1 ROUTE DESIGNATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2 1.2.2 TRAFFIC CONTROL DEVICE CLASSIFICATION . . . . . . . . . . . . . . . . . .1-2 1.3 SCOPE OF APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3 CHAPTER 2: TRAFFIC SIGNS — GENERAL 2.1 UNIFORMITY OF ATTRIBUTES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1 2.1.1 SHAPE CODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1 2.1.2 SIZE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1 2.1.3 COLOR CODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3 2.1.4 LEGENDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3 2.1.5 RETROREFLECTION AND ILLUMINATION . . . . . . . . . . . . . . . . . . . . .2-3 2.2 TRAFFIC SIGN PLACEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5 2.2.1 LATERAL PLACEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5 2.2.2 VERTICAL PLACEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-9 2.2.3 LONGITUDINAL PLACEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-9 2.2.4 OVERHEAD INSTALLATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-10 2.2.5 ORIENTATION ANGLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-10 CHAPTER 3: REGULATORY SIGNS 3.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1 3.1.1 FUNCTION AND OBJECTIVES OF REGULATORY SIGNS . . . . . . . . . .3-2 3.1.2 SUBCLASSIFICATION OF REGULATORY SIGNS . . . . . . . . . . . . . . . . .3-2 3.2 CONTROL SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-2 3.2.1 STOP SIGN 301 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-2 3.2.2 GIVE WAY (YIELD) SIGN 302 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3 3.2.3 GIVE WAY TO PEDESTRIANS SIGN 303 . . . . . . . . . . . . . . . . . . . . . . . .3-5 3.2.4 NO ENTRY SIGN 304 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-6 3.2.5 ONE WAY SIGNS 305, 306, AND 307 . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-6 3.3 MANDATORY SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-7 3.3.1 AHEAD ONLY SIGN 321 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-7 3.3.2 TURN RIGHT (OR LEFT) ONLY SIGN 322 (OR 323) . . . . . . . . . . . . . . .3-7 3.3.3 TURN RIGHT (OR LEFT) ONLY SIGN 324 (OR 325) . . . . . . . . . . . . . . .3-7 3.3.4 PASS EITHER SIDE SIGN 326 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-9 3.3.5 KEEP RIGHT (OR LEFT) SIGN 327 (OR 328) . . . . . . . . . . . . . . . . . . . .3-10 3.3.6 ROUNDABOUT SIGN 329 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-10 3.3.7 U-TURN SIGN 330 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-11 3.4 PROHIBITORY SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-11 3.4.1 MAXIMUM SPEED LIMIT SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-11 3.4.1.1 MAXIMUM SPEED LIMIT SIGNS 339 TO 344 . . . . . . . . . . . .3-11 3.4.1.2 DUAL SPEED LIMIT SIGN COMBINATION AND DUAL MAXIMUM SPEED LIMIT SIGN 345 . . . . . . . . . . . . . . . . . . .3-13

i

Version 0.1


Table of Contents

3.5

3.6

Page No.

3.4.2 NO LEFT (OR RIGHT) TURN SIGN 346 (OR 347) . . . . . . . . . . . . . . . . .3-15 3.4.3 NO U-TURN SIGN 348 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-16 3.4.4 NO OVERTAKING SIGN 349 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-16 3.4.5 NO INFLAMMABLE GOODS SIGN 350 . . . . . . . . . . . . . . . . . . . . . . . .3-17 3.4.6 NO GOODS VEHICLES SIGN 351 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-17 3.4.7 NO PEDESTRIANS SIGN 352 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-17 3.4.8 NO CYCLISTS SIGN 353 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-18 3.4.9 NO HORNS SIGN 354 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-18 3.4.10 MAXIMUM HEIGHT LIMIT SIGN 355 . . . . . . . . . . . . . . . . . . . . . . . . . .3-19 3.4.11 MAXIMUM HEIGHT LIMIT SIGN 356 . . . . . . . . . . . . . . . . . . . . . . . . . .3-19 3.4.12 QUALIFICATION PLATE SIGN 365 . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-19 PARKING CONTROL SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-20 3.5.1 NO STOPPING SIGNS 370, 371, 372, AND 373 . . . . . . . . . . . . . . . . . . .3-21 3.5.2 NO PARKING SIGNS 377, 378, AND 379 . . . . . . . . . . . . . . . . . . . . . . . .3-22 3.5.3 PAY-AND-DISPLAY PARKING SIGNS 383, 384, AND 385 . . . . . . . . . .3-23 3.5.4 PARKING FOR DISABLED PERSONS SIGNS 386, 387,, AND 388 . . . .3-23 3.5.5 PARKING TIME LIMIT SIGNS 389, 390, AND 391 . . . . . . . . . . . . . . . .3-23 3.5.6 BUS STOP SIGN 392 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-25 3.5.7 TAXI STAND SIGN 393 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-25 3.5.8 DROP-OFF PICK-UP ONLY SIGN 394 . . . . . . . . . . . . . . . . . . . . . . . . . .3-26 FREEWAY CONTROL SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-26 3.6.1 BEGINNING OF FREEWAY SIGN 398 . . . . . . . . . . . . . . . . . . . . . . . . . .3-26 3.6.2 END OF FREEWAY SIGN 399 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-27

CHAPTER 4: WARNING SIGNS 4.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1 4.1.1 FUNCTION AND OBJECTIVES OF WARNING SIGNS . . . . . . . . . . . . . .4-2 4.1.2 SUBCLASSIFICATION OF WARNING SIGNS . . . . . . . . . . . . . . . . . . . . .4-2 4.2 ADVANCE WARNING SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2 4.2.1 JUNCTION AHEAD SIGNS 401 TO 406 . . . . . . . . . . . . . . . . . . . . . . . . . .4-2 4.2.2 NO THROUGH ROAD SIGNS 407, 408, AND 409 . . . . . . . . . . . . . . . . . .4-4 4.2.3 MERGING TRAFFIC SIGNS 410 AND 411 . . . . . . . . . . . . . . . . . . . . . . . .4-5 4.2.4 RIGHT (OR LEFT) CURVE SIGN 412 (OR 413) . . . . . . . . . . . . . . . . . . . .4-5 4.2.5 BENDS AHEAD SIGN 414 AND 415 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-6 4.2.6 TWO-WAY TRAFFIC SIGN 416 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-6 4.2.7 LANE ENDS SIGNS 417 AND 418 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-7 4.2.8 U-TURN AHEAD SIGN 419 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-8 4.2.9 ROUNDABOUT AHEAD SIGN 420 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-8 4.2.10 ROAD NARROWS AHEAD SIGN 421 TO 423 . . . . . . . . . . . . . . . . . . . . .4-8 4.2.11 DUAL CARRIAGEWAY ENDS AHEAD SIGN 424 . . . . . . . . . . . . . . . . . .4-9 4.2.12 MAXIMUM HEADROOM SIGN 425 . . . . . . . . . . . . . . . . . . . . . . . . . . .4-10 4.2.13 CHILDREN SIGN 426 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-10 4.2.14 PEDESTRIAN CROSSING AHEAD SIGN 427 . . . . . . . . . . . . . . . . . . . .4-11 4.2.15 STOP CONTROL AHEAD SIGN 428 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-11 4.2.16 GIVE-WAY CONTROL AHEAD SIGN 429 . . . . . . . . . . . . . . . . . . . . . . .4-12 4.2.17 TRAFFIC SIGNALS AHEAD SIGN 430 . . . . . . . . . . . . . . . . . . . . . . . . .4-12 4.2.18 QUAYSIDE SIGN 431 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-13 4.2.19 DRAWBRIDGE AHEAD SIGN 432 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-13 4.2.20 ANIMALS AHEAD SIGN 433 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-13 4.2.21 LOW-FLYING AIRCRAFT SIGN 434 . . . . . . . . . . . . . . . . . . . . . . . . . . .4-14

Version 0.1

ii


Table of Contents

4.3

4.4

4.5

Page No.

4.2.22 SPEED HUMP AHEAD SIGN 435 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-14 4.2.23 TUNNEL SIGN 436 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-14 4.2.24 FALLING ROCK SIGN 437 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-15 4.2.25 SLIPPERY SURFACE SIGN 438 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-15 4.2.26 GENERAL WARNING SIGN 450 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-15 HAZARD MARKER SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-16 4.3.1 HAZARD PLATE SIGNS 451 AND 452 . . . . . . . . . . . . . . . . . . . . . . . . . .4-16 4.3.2 SINGLE CHEVRON RIGHT (OR LEFT) SIGN 454 (OR 455) . . . . . . . . .4-17 4.3.3 MULTIPLE CHEVRON RIGHT (OR LEFT) SIGN 456 (OR 457) . . . . . .4-19 4.3.4 T-JUNCTION CHEVRON SIGN 458 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-19 DIAGRAMMATIC SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-20 4.4.1 TRAFFIC MOVEMENT AFFECTED BY OBSTRUCTION SIGNS . . . . .4-21 4.4.1.1 LANE DROP SIGN 465 (FROM THE RIGHT) AND 466 (FROM THE LEFT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-21 4.4.1.2 BEGINNING/END OF MEDIAN SIGNS 472 AND 473 . . . . . .4-22 4.4.2 ADDITIONAL LANE AND LANES MERGE SIGNS . . . . . . . . . . . . . . .4-22 4.4.2.1 ADDITIONAL LANE SIGNS 480 AND 481 . . . . . . . . . . . . . . .4-23 4.4.2.2 JOINING LANE SIGNS 482 OR 483 . . . . . . . . . . . . . . . . . . . . .4-23 4.4.2.3 LANE MERGE SIGNS 490 AND 492 . . . . . . . . . . . . . . . . . . . .4-24 4.4.3 LANE USE CONTROL BY REGULATION . . . . . . . . . . . . . . . . . . . . . . .4-24 4.4.3.1 LANE USE CONTROL — TRUCKS AND BUSSES SIGNS 484 AND 485 . . . . . . . . . . . . . . . . . . . . . . . . .4-24 4.4.3.2 LANE USE CONTROL — DIRECTIONAL RESTRICTION SIGN 486 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-25 HIGH VEHICLE WARNING SIGN 495 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-25

CHAPTER 5: GUIDE SIGNS 5.1 PRINCIPLES OF DIRECTIONAL GUIDANCE . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1 5.5.1 METHOD OF PROVIDING GUIDANCE . . . . . . . . . . . . . . . . . . . . . . . . .5-1 5.1.2 CLASSIFICATION OF GUIDE SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1 5.1.3 ROUTE NUMBERING SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-2 5.1.4 PRIMARY DESTINATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-2 5.1.4.1 CONTROL DESTINATIONS FOR EMIRATE ROUTES . . . . . . .5-4 5.1.4.2 CONTROL DESTINATIONS FOR NON-EMIRATE ROUTES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-4 5.1.4.3 OTHER LOCAL DESTINATIONS FOR NON-EMIRATE ROUTES . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-4 5.1.5 SUPPLEMENTAL DESTINATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-5 5.1.6 COLOR CODING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-5 5.1.7 INFORMATION TO BE DISPLAYED ON SIGNS . . . . . . . . . . . . . . . . . . .5-6 5.1.8 DESTINATIONS NOT ELIGIBLE FOR DISPLAY ON GUIDE SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-7 5.1.9 TRAILBLAZING SIGNING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-7 5.2 GENERAL STANDARDS FOR GUIDE SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . .5-8 5.2.1 LANGUAGE AND LETTERING STYLES . . . . . . . . . . . . . . . . . . . . . . . .5-8 5.2.2 AMOUNT OF LEGEND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-8 5.2.3 SIZE OF LETTERING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-9 5.2.4 SIGN BORDERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-13 5.2.5 INTERNAL SPACING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-13 5.2.6 ARROWS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-13

iii

Version 0.1


Table of Contents

5.3

5.4

5.5

Version 0.1

Page No.

5.2.6.1 CHEVRON ARROW TYPES 1 AND 2 . . . . . . . . . . . . . . . . . . .5-13 5.2.6.2 STACK SIGN ARROW TYPE 3 . . . . . . . . . . . . . . . . . . . . . . . .5-14 5.2.6.3 STACK SIGN ARROW TYPES 4 AND 5 . . . . . . . . . . . . . . . . .5-14 5.2.6.4 STACK SIGN ARROW TYPE 6 . . . . . . . . . . . . . . . . . . . . . . . .5-14 5.2.6.5 DOWNWARD POINTING ARROW TYPE 7 . . . . . . . . . . . . . .5-17 5.2.6.6 UPWARD POINTING ARROW TYPE 8 . . . . . . . . . . . . . . . . . .5-17 5.2.6.7 MAP ARROW TYPE 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-17 5.2.7 ROUTE NUMBER EMBLEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-18 5.2.7.1 EMIRATE ROUTE EMBLEM . . . . . . . . . . . . . . . . . . . . . . . . . .5-18 5.2.7.2 ABU DHABI ROUTE EMBLEM . . . . . . . . . . . . . . . . . . . . . . .5-18 5.2.8 SUPPLEMENTAL DESTINATION SIGN SYMBOLS . . . . . . . . . . . . . . .5-19 ROUTE MARKER SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-19 5.3.1 USE OF ROUTE MARKER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-19 5.3.2 EMIRATE ROUTE MARKER SIGN 501 . . . . . . . . . . . . . . . . . . . . . . . . .5-20 5.3.3 ABU DHABI ROUTE MARKER SIGN 502 . . . . . . . . . . . . . . . . . . . . . . .5-20 TRAILBLAZING SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-22 5.4.1 USE OF TRAILBLAZING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-22 5.4.2 AIRPORT TRAILBLAZER SIGN 503 . . . . . . . . . . . . . . . . . . . . . . . . . . .5-23 5.4.3 CITY CENTER TRAILBLAZER SIGN 504 . . . . . . . . . . . . . . . . . . . . . . .5-23 5.4.4 EMIRATE ROUTE TRAILBLAZER SIGN 505 . . . . . . . . . . . . . . . . . . . .5-23 5.4.5 ABU DHABI ROUTE TRAILBLAZER SIGN 506 . . . . . . . . . . . . . . . . . .5-24 5.4.6 SUPPLEMENTAL DESTINATION TRAILBLAZER SIGN 507 . . . . . . . .5-24 5.4.7 FREEWAY TRAILBLAZER SIGN 508 . . . . . . . . . . . . . . . . . . . . . . . . . .5-25 5.4.8 PARKING TRAILBLAZER SIGN 509 . . . . . . . . . . . . . . . . . . . . . . . . . . .5-25 AT-GRADE JUNCTION SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-25 5.5.1 TYPES OF AT-GRADE JUNCTION SIGNS . . . . . . . . . . . . . . . . . . . . . . .5-25 5.5.2 ADVANCE HORIZONTAL STACK SIGN 511 . . . . . . . . . . . . . . . . . . . . .5-26 5.5.2.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-26 5.5.2.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-26 5.5.2.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-26 5.5.2.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-26 5.5.3 ADVANCE VERTICAL STACK SIGN 512 . . . . . . . . . . . . . . . . . . . . . . .5-27 5.5.3.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-27 5.5.3.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-27 5.5.3.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-28 5.5.3.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-28 5.5.4 ADVANCE MAP SIGN 513 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-29 5.5.4.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-29 5.5.4.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-29 5.5.4.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-29 5.5.4.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-29 5.5.5 ADVANCE SUPPLEMENTAL SIGN 514 . . . . . . . . . . . . . . . . . . . . . . . . .5-31 5.5.5.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-31 5.5.5.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-31 5.5.5.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-31 5.5.5.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-31 5.5.6 CHEVRON DIRECTION SIGN 515 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-32 5.5.6.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-32 5.5.6.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-32 5.5.6.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-32

iv


Table of Contents

5.6

5.7

Page No.

5.5.6.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-33 GRADE-SEPARATED JUNCTION SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-34 5.6.1 TYPES OF GRADE-SEPARATED JUNCTION SIGNS . . . . . . . . . . . . . .5-34 5.6.2 ADVANCE EXIT DIRECTION SIGN 551 . . . . . . . . . . . . . . . . . . . . . . . .5-35 5.6.2.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-35 5.6.2.2 APPLICATION AND LOCATION . . . . . . . . . . . . . . . . . . . . . .5-35 5.6.2.3 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-37 5.6.3 EXIT DIRECTION SIGN 552 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-40 5.6.3.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-40 5.6.3.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-40 5.6.3.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-40 5.6.3.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-40 5.6.4 ONGOING DIRECTION SIGN 553 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-44 5.6.4.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-44 5.6.4.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-44 5.6.4.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-44 5.6.4.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-44 5.6.5 GORE EXIT SIGNS 554 AND 556 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-47 5.6.5.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-47 5.6.5.2 APPLICATION AND LOCATION . . . . . . . . . . . . . . . . . . . . . . .5-47 5.6.5.3 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-47 5.6.6 SUPPLEMENTAL EXIT SIGN 557 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-48 5.6.6.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-48 5.6.6.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-48 5.6.6.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-48 5.6.6.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-48 GENERAL INFORMATION SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-49 5.7.1 DISTANCE SIGN 585 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-49 5.7.1.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-49 5.7.1.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-49 5.7.1.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-49 5.7.1.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-49 5.7.2 HIGH VEHICLE EXIT SIGN 586 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-50 5.7.2.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-50 5.7.2.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-50 5.7.2.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-50 5.7.3 TEXT SIGN 588 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-50 5.7.3.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-50 5.7.3.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-50 5.7.3.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-51 5.7.3.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-51 5.7.4 SUPPLEMENTARY PLATE SIGN 589 . . . . . . . . . . . . . . . . . . . . . . . . . . .5-51 5.7.4.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-51 5.7.4.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-51 5.7.4.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-51 5.7.4.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-51 5.7.5 FIRE HYDRANT SUPPLEMENTARY PLATE SIGN 590 . . . . . . . . . . . .5-52 5.7.5.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-52 5.7.5.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-52 5.7.5.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-52

v

Version 0.1


Table of Contents

Page No.

5.7.5.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-52 GENERAL SERVICE SIGN 591 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-52 5.7.6.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-52 5.7.6.2 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-52 5.7.6.3 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-53 5.7.6.4 DISPLAY OF INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . .5-53 MUNICIPALITY PARKING STRUCTURE SIGNS . . . . . . . . . . . . . . . . . . . . . . .5-54 5.8.1 MUNICIPALITY PARKING STRUCTURE TRAILBLAZER SIGN 595 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-54 5.8.2 MUNICIPALITY PARKING STRUCTURE ENTRANCE BANNER SIGN 596 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-54 5.8.3 MUNICIPALITY PARKING STRUCTURE ENTRANCE SIGN 597 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-55 5.8.4 MUNICIPALITY PARKING STRUCTURE EXIT SIGN 598 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-55 5.7.6

5.8

CHAPTER 6: PAVEMENT MARKINGS 6.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-1 6.1.1 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-1 6.1.2 MARKING TYPES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-1 6.1.3 COLOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-2 6.1.4 CONFIGURATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-2 6.1.5 IMPLEMENTATION OF THIS PAVEMENT-MARKING GUIDANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-3 6.2 REGULATORY MARKINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-3 6.2.1 STOP LINE MARKING 601 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-4 6.2.2 GIVE WAY LINE MARKING 602 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-4 6.2.3 PEDESTRIAN CROSSING MARKING 603 . . . . . . . . . . . . . . . . . . . . . . .6-6 6.2.4 NO PASSING LINE MARKING 611 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-6 6.2.5 CHANNELIZING LINE MARKING 612 . . . . . . . . . . . . . . . . . . . . . . . . . .6-7 6.2.6 EDGE LINE MARKING 613 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-8 6.2.7 LANE DIRECTION ARROW MARKINGS 614 TO 619 (INCLUDING STRAIGHT, RIGHT TURN, LEFT TURN, STRAIGHT/RIGHT, STRAIGHT/LEFT, AND RIGHT/LEFT) . . . . . . . . . .6-8 6.2.8 PARKING ENVELOPE LINE MARKING 620 . . . . . . . . . . . . . . . . . . . . .6-10 6.2.9 PARKING SPACE LINE 621 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-12 6.3 WARNING MARKINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-12 6.3.1 RUMBLE STRIPS MARKING 650 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-12 6.3.2 SPEED HUMP MARKING 651 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-16 6.3.3 DIVIDING LINE MARKING 652 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-17 6.3.4 LANE LINE MARKING 654 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-17 6.3.5 LANE END ARROW MARKING 656 . . . . . . . . . . . . . . . . . . . . . . . . . . .6-17 6.3.6 CHEVRON MARKING 657 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-18 6.3.7 HATCH MARKING 658 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-18 6.4 GUIDANCE MARKINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-18 6.4.1 GUIDE LINE MARKING 680 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-18 6.4.2 CONTINUITY LINE MARKING 661 . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-19 6.5 RAISED PAVEMENT MARKERS (RPM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-19 6.5.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-20 6.5.2 RETROREFLECTIVE RPM MARKING R . . . . . . . . . . . . . . . . . . . . . . .6-20

Version 0.1

vi


Table of Contents

Page No.

6.5.3 NONRETROREFLECTIVE RPM MARKING N . . . . . . . . . . . . . . . . . . .6-22 CURB PAINTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-22 6.6.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-22 6.6.2 NO PARKING MARKING 690 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-22 6.6.3 VISIBILITY PAINTING MARKING 691 . . . . . . . . . . . . . . . . . . . . . . . . .6-23 6.7 OBJECT MARKERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-23 6.7.1 OBJECT MARKER DESIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-23 6.7.2 OBJECTS IN THE ROADWAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-24 6.7.3 OBJECTS ADJACENT TO THE ROADWAY . . . . . . . . . . . . . . . . . . . . . .6-24 6.8 TEXT PAVEMENT MARKINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-24 6.8.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-24 6.8.2 TEXT SYMBOL MARKINGS 695 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-25 6.9 DELINEATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-27 6.9.1 DELINEATORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-27 6.9.2 DESIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-27 6.9.3 CURB MARKINGS FOR DELINEATION . . . . . . . . . . . . . . . . . . . . . . . .6-27 6.9.4 DELINEATOR APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-27 6.9.5 DELINEATOR PLACEMENT AND SPACING . . . . . . . . . . . . . . . . . . . .6-28 6.10 BARRICADES AND CHANNELIZING DEVICES . . . . . . . . . . . . . . . . . . . . . . .6-28 6.10.1 BARRICADES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-28 6.10.2 CHANNELIZING DEVICES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-28 6.11 CURB PAINTING AND PAVEMENT MARKING FOR FIRE HYDRANTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-30 6.11.1 CURB PAINTING FOR FIRE HYDRANTS ALONG ROADWAYS MARKING 695 . . . . . . . . . . . . . . . . . . . . . . . . . .6-30 6.11.2 CURB PAINTING AND PAVEMENT MARKING FOR FIRE HYDRANTS ADJACENT TO PARKING SPACES . . . . . . . .6-30 6.6

CHAPTER 7: ROADWORKS TRAFFIC CONTROL 7.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-1 7.1.1 BASIC PRINCIPLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-1 7.1.1.1 SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-1 7.1.1.2 UNIFORMITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-1 7.1.1.3 FUNCTIONALITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-2 7.1.1.4 MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-2 7.1.2 TRAFFIC CONTROL ZONE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-2 7.1.2.1 ADVANCE WARNING AREA . . . . . . . . . . . . . . . . . . . . . . . . . .7-4 7.1.2.2 TRANSITION AREA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-4 7.1.2.3 STABILIZATION AREA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-4 7.1.2.4 WORK AREA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-5 7.1.2.5 TERMINATION AREA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-5 7.1.3 DEPLOYING ROADWORKS DEVICES . . . . . . . . . . . . . . . . . . . . . . . . . .7-5 7.2 TRAFFIC SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-6 7.2.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-6 7.2.2 REGULATORY SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-6 7.2.2.1 CONTROL SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-6 7.2.2.2 MANDATORY SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-11 7.2.2.3 PROHIBITORY SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-11 7.2.2.4 PARKING CONTROL SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . .7-11 7.2.2.5 FREEWAY CONTROL SIGNS . . . . . . . . . . . . . . . . . . . . . . . . .7-12

vii

Version 0.1


Table of Contents

Page No.

7.2.3

7.3

7.4

WARNING SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-12 7.2.3.1 ADVANCE WARNING SIGNS . . . . . . . . . . . . . . . . . . . . . . . . .7-12 7.2.3.2 HAZARD MARKER SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . .7-14 7.2.3.3 DIAGRAMMATIC WARNING SIGNS . . . . . . . . . . . . . . . . . . .7-14 7.2.4 GUIDE SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-16 CHANNELIZATION DEVICES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-17 7.3.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-17 7.3.2 PAVEMENT MARKINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-17 7.3.2.1 PAINTED MARKINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-18 7.3.2.2 RAISED PAVEMENT MARKERS . . . . . . . . . . . . . . . . . . . . . . .7-19 7.3.3 CONES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-19 7.3.3.1 TRAFFIC CONE DEVICE 7459 . . . . . . . . . . . . . . . . . . . . . . . .7-20 7.3.3.2 CONE DESIGN PARAMETERS . . . . . . . . . . . . . . . . . . . . . . . .7-20 7.3.3.3 CONE APPLICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-20 7.3.4 BARRIERS AND BARRICADES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-21 7.3.4.1 BARRICADE DEVICE 7460 . . . . . . . . . . . . . . . . . . . . . . . . . . .7-21 7.3.4.2 BARRIERS AND BARRICADE DESIGN PARAMETERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-21 7.3.4.3 BARRIER AND BARRICADE APPLICATIONS . . . . . . . . . . . .7-24 7.3.5 DELINEATORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-24 7.3.5.1 DELINEATOR SIGNS 7454 AND 7455 . . . . . . . . . . . . . . . . . . .7-24 7.3.5.2 DELINEATOR DESIGN PARAMETERS . . . . . . . . . . . . . . . . .7-25 7.3.5.3 DELINEATOR APPLICATIONS . . . . . . . . . . . . . . . . . . . . . . . .7-25 7.3.6 OBJECT MARKERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-25 7.3.7 DRUM DEVICE 7461 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-25 7.3.8 ILLUMINATED DEVICES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-26 7.3.8.1 WARNING AND DELINEATION LIGHTS . . . . . . . . . . . . . . . .7-26 7.3.8.2 WARNING ARROW SIGN PANELS SIGN 7462 . . . . . . . . . . .7-26 7.3.8.3 ILLUMINATED DEVICE APPLICATIONS . . . . . . . . . . . . . . .7-28 7.3.9 FLOODLIGHTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-29 OTHER FORMS OF TRAFFIC CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-29 7.4.1 HAND SIGNALING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-29 7.4.2 PILOT CAR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-30 7.4.3 TEMPORARY TRAFFIC SIGNALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-30

CHAPTER 8: TYPICAL APPLICATIONS 8.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-1 8.2 AT-GRADE JUNCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-1 8.2.1 ROAD JUNCTIONS IN COMMUNITY AREAS . . . . . . . . . . . . . . . . . . . .8-1 8.2.2 ARTERIAL MIDBLOCK U-TURN AND LOCAL T-JUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-3 8.2.3 ARTERIAL MIDBLOCK LEFT TURN AT LOCAL ROAD T-JUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-3 8.2.4 SERVICE ROAD CONNECTIONS TO AN ARTERIAL . . . . . . . . . . . . . .8-6 8.2.5 LARGE ROUNDABOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-8 8.2.6 LARGE SIGNALIZED ROUNDABOUT . . . . . . . . . . . . . . . . . . . . . . . . . .8-8 8.2.7 SIGNALIZED INTERSECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-11 8.2.8 FREEWAY CROSSROADS WITH SMALL ROUNDABOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-11

Version 0.1

viii


Table of Contents

Page No.

8.2.9

8.3

8.4

8.5

FREEWAY CROSSROADS AT A SIGNALIZED DIAMOND INTERCHANGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-14 8.2.10 MINI ROUNDABOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-16 GRADE-SEPARATED JUNCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-16 8.3.1 FREEWAY WITH ONE-LANE EXIT, NO LANE DROP . . . . . . . . . . . . .8-16 8.3.2 FREEWAY WITH TWO-LANE EXIT, ONE LANE DROP . . . . . . . . . . . .8-19 8.3.3 INTERCHANGE WITH A C-D ROAD . . . . . . . . . . . . . . . . . . . . . . . . . . .8-19 8.3.4 FREEWAY SYSTEMS INTERCHANGE WITH TWO CLOSELY SPACED EXITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-22 8.3.5 FREEWAY SYSTEMS INTERCHANGE WITH A TWO-LANE EXIT AND RAMP SPLIT . . . . . . . . . . . . . . . . . . . . . . . .8-22 8.3.6 FREE-FLOW RAMP CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-25 ROADWORKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-25 8.4.1 TYPICAL TAPER DETAIL — TRANSITION AREA . . . . . . . . . . . . . . . .8-25 8.4.2 TYPICAL CROSSOVER DETAIL — TRANSITION AREA . . . . . . . . . .8-28 8.4.3 TYPICAL TAPER DETAIL — TERMINATION AREA . . . . . . . . . . . . . .8-28 8.4.4 SHORT WORK SITE — TWO-WAY TRAFFIC . . . . . . . . . . . . . . . . . . . .8-28 8.4.5 WORK SITE CLOSE TO SIDE ROAD . . . . . . . . . . . . . . . . . . . . . . . . . . .8-28 8.4.6 ROAD CLOSURE DETOUR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-33 8.4.7 MAINTENANCE WORK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-33 8.4.8 TYPICAL TWO-LANE TAPER DETAIL — TRANSITION AREA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-36 8.4.9 MINOR-ROAD SINGLE-LANE OPERATION . . . . . . . . . . . . . . . . . . . . .8-36 SCHOOL ZONE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-36

CHAPTER 9: SIGNALS 9.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-1 9.1.1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-1 9.1.2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-1 9.1.3 ADVANTAGES AND DISADVANTAGES OF TRAFFIC CONTROL SIGNALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-4 9.1.4 AREA OF CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-4 9.1.5 TYPES OF TRAFFIC CONTROL SIGNALS . . . . . . . . . . . . . . . . . . . . . . .9-4 9.1.6 PORTABLE TRAFFIC CONTROL SIGNALS . . . . . . . . . . . . . . . . . . . . . .9-5 9.2 TRAFFIC CONTROL SIGNAL INDICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . .9-5 9.2.1 MEANING OF VEHICULAR TRAFFIC CONTROL SIGNAL INDICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-5 9.2.1.1 GREEN TRAFFIC SIGNAL INDICATION . . . . . . . . . . . . . . . . .9-5 9.2.1.2 YELLOW TRAFFIC SIGNAL INDICATION . . . . . . . . . . . . . . .9-5 9.2.1.3 RED TRAFFIC SIGNAL INDICATION . . . . . . . . . . . . . . . . . . .9-5 9.2.2 USE OF TRAFFIC CONTROL SIGNAL INDICATIONS . . . . . . . . . . . . . .9-6 9.2.2.1 NONFLASHING INDICATIONS . . . . . . . . . . . . . . . . . . . . . . . .9-6 9.2.2.2 ARROW INDICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-6 9.2.2.3 PROHIBITED COMBINATIONS OF TRAFFIC CONTROL SIGNAL INDICATIONS . . . . . . . . . . . . . . . . . . . . . .9-7 9.2.2.4 INDICATIONS THAT MAY FOLLOW OTHER INDICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-7 9.3 DESIGN AND LOCATION OF VEHICULAR TRAFFIC CONTROL INDICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-7 9.3.1 SIZE AND DESIGN OF TRAFFIC SIGNAL LENSES . . . . . . . . . . . . . . . .9-7

ix

Version 0.1


Table of Contents

Page No.

9.3.2

9.4

9.5

9.6

Version 0.1

NUMBER AND ARRANGEMENT OF INDICATIONS IN A TRAFFIC CONTROL SIGNAL FACE . . . . . . . . . . . . . . . . . . . . . . .9-11 9.3.3 ILLUMINATION OF TRAFFIC CONTROL LENSES . . . . . . . . . . . . . . .9-11 9.3.4 VISIBILITY AND SHIELDING OF SIGNAL FACES . . . . . . . . . . . . . . .9-11 9.3.5 NUMBER AND LOCATION OF SIGNAL FACES . . . . . . . . . . . . . . . . . .9-12 9.3.6 HEIGHT OF SIGNAL FACES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-15 9.3.7 DESIGN AND LOCATION OF TRAFFIC CONTROL SIGNAL SUPPORTS AND CONTROLLER CABINETS FOR SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-15 SIGNAL USE CRITERIA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-22 9.4.1 FACTORS TO BE CONSIDERED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-22 9.4.2 ENGINEERING DATA REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . .9-23 9.4.3 CRITERION 1 — MINIMUM VEHICULAR VOLUME . . . . . . . . . . . . .9-23 9.4.4 CRITERION 2 — INTERRUPTION OF CONTINUOUS TRAFFIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-30 9.4.5 CRITERION 3 — MINIMUM PEDESTRIAN VOLUME . . . . . . . . . . . . .9-31 9.4.6 CRITERION 4 — SCHOOL CROSSING . . . . . . . . . . . . . . . . . . . . . . . . .9-31 9.4.7 CRITERION 5 — PROGRESSIVE MOVEMENT . . . . . . . . . . . . . . . . . .9-33 9.4.8 CRITERION 6 — ACCIDENT EXPERIENCE . . . . . . . . . . . . . . . . . . . . .9-33 9.4.9 CRITERION 7 — COMBINATION OF CRITERIA . . . . . . . . . . . . . . . . .9-34 9.4.10 CRITERION 8 — SHORT PEAK PERIOD TRAFFIC VOLUME CRITERION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-34 9.4.11 CRITERION 9 — ESTIMATE OF TRAFFIC ON STREET TO BE CONSTRUCTED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-36 9.4.12 SELECTION OF PRETIMED OR TRAFFIC-ACTUATED CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-36 9.4.13 PEDESTRIAN ACTUATION OF TRAFFIC CONTROL SIGNALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-37 9.4.14 SIGNAL CRITERIA ANALYSIS FORM . . . . . . . . . . . . . . . . . . . . . . . . .9-37 TRAFFIC CONTROL SIGNAL OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-37 9.5.1 VEHICLE CHANGE AND CLEARANCE INTERVALS . . . . . . . . . . . . .9-37 9.5.2 PREVENTION OF UNEXPECTED TRAFFIC CONFLICTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-41 9.5.3 PROTECTIVE FAIL-SAFE CIRCUITRY . . . . . . . . . . . . . . . . . . . . . . . . .9-41 9.5.4 SEQUENCE OF TRAFFIC CONTROL SIGNAL INDICATIONS (OPERATING PLANS) . . . . . . . . . . . . . . . . . . .9-41 9.5.5 COORDINATION OF TRAFFIC CONTROL SIGNALS . . . . . . . . . . . . .9-62 9.5.6 FLASHING OPERATION OF TRAFFIC CONTROL SIGNALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-62 9.5.7 CONTINUITY OF OPERATION OF TRAFFIC CONTROL SIGNALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-63 9.5.8 CONTROL PREEMPTION BY PRIORITY TRAFFIC . . . . . . . . . . . . . . .9-63 9.5.9 MAINTENANCE OF TRAFFIC CONTROL SIGNALS . . . . . . . . . . . . . .9-63 9.5.10 VEHICLE SENSORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-64 9.5.11 USE OF SIGNS WITH TRAFFIC CONTROL DEVICES . . . . . . . . . . . . .9-65 9.5.12 OPERATION OF TRAFFIC CONTROL SIGNALS BY HAND CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-65 PEDESTRIAN SIGNAL INDICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-65 9.5.1 MEANING OF PEDESTRIAN SIGNAL INDICATIONS . . . . . . . . . . . . .9-65 9.5.2 USE OF PEDESTRIAN SIGNAL INDICATIONS . . . . . . . . . . . . . . . . . .9-66

x


Table of Contents

Page No.

9.6.3 9.6.4 9.6.5 9.6.6 9.7

DESIGN OF PEDESTRIAN SIGNAL INDICATIONS . . . . . . . . . . . . . . .9-66 LOCATION OF PEDESTRIAN SIGNAL INDICATIONS . . . . . . . . . . . .9-67 PEDESTRIAN PUSHBUTTON DETECTORS . . . . . . . . . . . . . . . . . . . . .9-67 PEDESTRIAN SIGNAL PHASES AND INTERVAL TIMING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-67 FLASHING BEACONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-68 9.7.1 HAZARD IDENTIFICATION BEACONS . . . . . . . . . . . . . . . . . . . . . . . .9-68 9.7.2 SPEED LIMIT SIGN BEACON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-68 9.7.3 INTERSECTION CONTROL BEACON . . . . . . . . . . . . . . . . . . . . . . . . . .9-69 9.7.4 STOP SIGN BEACON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-69 9.7.5 DESIGN AND OPERATION OF FLASHING BEACONS . . . . . . . . . . . .9-69

LIST OF FIGURES 1-1 Classification of Traffic Control Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3 1-2 Roads Owned and Managed by the Abu Dhabi Municipality Road Department . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4 2-1 Standard Sign Shapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2 2-2 Lateral and Vertical Positioning of Regulatory and Warning Signs . . . . . . . . . . . . . . . . . . .2-7 2-3 Lateral and Vertical Positioning of Guide and General Information Signs . . . . . . . . . . . . . .2-8 2-4 Sign Orientation Angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-10 3-1 Longitudinal Position of Stop Sign 301 and Give Way Sign 302 . . . . . . . . . . . . . . . . . . . .3-4 3-2 Use of One Way Signs 305, 306, and 307 with Signs 346 and 347 . . . . . . . . . . . . . . . . . . .3-8 3-3 Typical Use of Maximum Speed Limit Signs 340 to 344 . . . . . . . . . . . . . . . . . . . . . . . . .3-14 3-4 Dual Speed Limit Sign Combination (typical) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-15 3-5 No Stopping Sign Variants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-21 3-6 No Stopping with Time Limit Displays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-22 3-7 No Parking Sign Variants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-22 3-8 Pay and Display Parking Sign Variants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-23 3-9 Parking for Disabled Persons Sign Variants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-24 3-10 Parking Time Limit Sign Variants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-24 3-11 Examples of Sign Combinations in the Parking Group . . . . . . . . . . . . . . . . . . . . . . . . . . .3-25 4-1 Typical Hazard Plate Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-17 4-2 Examples of Applications of Sign 454 and Sign 455 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-18 4-3 Typical Application of Multiple Chevron Signs 456 and 457 . . . . . . . . . . . . . . . . . . . . . .4-19 5-1 Route Numbering System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-3 5-2 Principles of Legibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-12 5-3 Typical Guidesign Internal Spacing Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-14 5-4 Arrow-Type Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-15 5-5 Approved Supplemental Destination Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-20 5-6 Use of Route Marker Signs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-21 5-7 Advance Direction Sign 551 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-36 5-8 Exit Direction Sign 552 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-41 5-9 Ongoing Direction Sign 553 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-45 5-10 Gore Exit Signs 554 and 556 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-47 5-11 Supplemental Exit Sign 557 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-48 5-12 Sign 590 with No Stopping Sign 370 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-52 5-13 General Services Iconic Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-54 6-1 Use of No Passing Line 611 at Junction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-4 6-2 Transverse Regulatory Pavement Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-5 6-3 Longitudinal Regulatory Pavement Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-9

xi

Version 0.1


Table of Contents 6-4 6-5 6-6 6-7 6-8 6-9 6-10 6-11 6-12 6-13 6-14 7-1 7-2 7-3 7-4 7-5 7-6 7-7 8-1 8-2 8-3 8-4 8-5 8-6 8-7 8-8 8-9 8-10 8-11 8-12 8-13 8-14 8-15 8-16 8-17 8-18 8-19 8-20 8-21 8-22 8-23 8-24 8-25 8-26 9-1 9-2 9-3 9-4

Version 0.1

Page No.

Typical Regulatory Arrow Pavement Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-11 Warning Pavement Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-13 Combined Regulatory and Warning Pavement Markings as Painted Islands . . . . . . . . . . .6-14 Guidelines for Using Rumble Strip Marking 650 for Speed Reduction . . . . . . . . . . . . . . .6-15 Guidance Pavement Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-19 Use of Raised Pavement Markers (RPMs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-21 Object Markers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-25 Typical Delineator Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-26 Barricades and Channelizing Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-29 Curb Painting for Fire Hydrants Along Roadways Marking 695 . . . . . . . . . . . . . . . . . . . .6-31 Curb Painting and Pavement Marking for Fire Hydrants Adjacent to Parking Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-32 Roadworks Zone Traffic Control Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-3 Regulatory Signs at Roadworks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-7 Warning Signs at Roadworks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-8 Diagrammatic Signs at Roadworks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-9 Guide Signs at Roadworks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-10 Examples of Directional Barricade Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-22 Examples of Nondirectional Barricade Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-23 Road Junctions in Community Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-2 Arterial Midblock U-Turn and Local Road T-Junction . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-4 Arterial Midblock Left Turn at Local Road T-Junction . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-5 Service Road Connections to an Arterial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-7 Large Roundabout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-9 Large Signalized Roundabout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-10 Signalized Roundabout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-12 Freeway Crossroads with Small Roundabout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-13 Freeway Crossroads at a Signalized Diamond Interchange . . . . . . . . . . . . . . . . . . . . . . . .8-15 Mini Roundabout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-17 Freeway with One-Lane Exit, No Lane Drop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-18 Freeway with Two-Lane Exit, One Lane Drop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-20 Interchange with a C-D Road . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-21 Freeway Systems Interchange with Two Closely Spaced Exits . . . . . . . . . . . . . . . . . . . . .8-23 Freeway Systems Interchange with a Two-Lane Exit and Ramp Split . . . . . . . . . . . . . . . .8-24 Free-Flow Ramp Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-26 Typical Taper Detail — Transition Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-27 Typical Crossover Detail — Transition Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-29 Typical Taper Detail — Termination Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-30 Short Work Site — Two-Way Traffic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-31 Work Site Close to Side Road . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-32 Road Closure Detour . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-34 Maintenance Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-35 Typical Two-Lane Taper Detail — Transition Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-37 Minor-Road Single-Lane Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-38 School Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-39 Typical Arrangements of Indications on Signal Faces . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-11 Required Location of Signal Faces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-14 Signal Face Location and Indications without Pedestrian Signals . . . . . . . . . . . . . . . . . . .9-16 Signal Face Location and Indications with Pedestrian Signals . . . . . . . . . . . . . . . . . . . . .9-17

xii


Table of Contents 9-5 9-6 9-7 9-8 9-9 9-10 9-11 9-12 9-13 9-14 9-15 9-16 9-17 9-18 9-19 9-20 9-21 9-22 9-23 9-24 9-25

9-26

9-27

9-28 9-29 9-30A 9-30B 9-31A 9-31B 9-32 9-33 9-34 9-35 9-36

Page No.

Signal Face Location and Indications — School or Pedestrian Midblock Crossings (push-button signal) . . . . . . . . . . . . . . . . . . . . .9-18 School or Pedestrian Midblock Crossings (flashing amber) . . . . . . . . . . . . . . . . . . . . . . .9-19 Typical Mast Arm Mounting of Signal Heads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-20 Typical Pole Mounting of Signal Heads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-21 Vehicle Volume Count Field Data Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-24 Traffic Volume Summary Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-25 Pedestrian Count Field Data Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-26 Condition Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-27 Typical Collision Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-28 Vehicle Speed Study Field Data Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-29 Example of a Test for Criterion 2, Interruption of Continuous Traffic . . . . . . . . . . . . . . . .9-32 Peak Hour Volume Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-35 Peak Hour Volume Criteria (less than 10,000 population or above 65 km/h) . . . . . . . . . . .9-35 Completed Traffic Signal Criteria Analysis Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-38 Standard Four-Phase Traffic Signal — Without Pedestrian Signals . . . . . . . . . . . . . . . . . .9-44 Signal Operating Plan No. 1 — Standard Signal Operating Plan — Without Pedestrian Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-45 Signal Operating Plan No. 2 — Standard Signal Operating Plan — With Pedestrian Crossings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-46 Signal Operating Plan No. 3 — Leading Protected/Permissive Left Turn From One Approach — With Pedestrian Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-47 Signal Operating Plan No. 4 — Permissive Left Turn on Green Disk From Opposite Approaches — With Pedestrian Signals . . . . . . . . . . . . . . . . . . . . . . . . . .9-48 Signal Operating Plan No. 5 — Leading Protected/Permissive Left Turn From Opposite Approaches — With Pedestrian Signals . . . . . . . . . . . . . . . . . . . . . . . . . .9-49 Signal Operating Plan No. 6 — Leading Protected/Prohibited Left Turn From One Approach Intersection With One-Way Street — With Pedestrian Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-50 Signal Operating Plan No. 7 — Intersection of Two Divided Streets With Service Roads — Stop or Signal Control on the Service Roads — Without Pedestrian Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-51 Signal Operating Plan No. 8 — Leading Protected/Prohibited Left Turn From Two Approaches — Leading Protected/Permissive Left Turn From Two Other Approaches — Intersection of Two Divided Streets With Left-Turn Bays — With Pedestrian Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-52 Signal Operating Plan No. 9 — “T” Intersection With a One-Way Service Road Along the Principal Street — Without Pedestrian Signals . . . . . . . . . . . . . . . . . . . .9-53 Signal Operating Plan No. 10 — “T” Intersection With Left-Turn Bay — Continuous Traffic on the Principal Street . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-54 Intersection Plan — Traffic-Actuated Signal With Pedestrian Signals . . . . . . . . . . . . . . . .9-55 Movements Doing Each of the Phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-55 Table of Conflicting and Nonconflicting Phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-56 Signal Indications to be Used in the Change and Clearance Intervals . . . . . . . . . . . . . . . .9-57 Three-Phase, Lead-Lag Diamond Interchange Ramp Signal Sequence . . . . . . . . . . . . . . .9-58 Four-Phase Diamond Interchange Ramp Signal Sequence . . . . . . . . . . . . . . . . . . . . . . . .9-59 Four-Phase, Two-Overlap Diamond Interchange Ramp Signal System . . . . . . . . . . . . . . .9-60 Three-Phase, Lag-Lag Diamond Interchange Ramp Signal System . . . . . . . . . . . . . . . . . .9-61 Pedestrian Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-66

xiii

Version 0.1


Table of Contents

Page No.

LIST OF TABLES 1-1 Roadway Types by Functional Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2 2-1 Regulatory and Warning Sign Sizes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3 2-2 Traffic Sign Background and Legend Colors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4 2-3 Lateral and Vertical Positioning of Traffic Signs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6 3-1 Guidelines for Speed Limit Sign Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-13 4-1 Guidelines for Positioning Advance Warning Signs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1 4-2 Junction Spacing Requirements for Signs 405 and 406 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-4 4-3 Spacing on Curves for Signs 451, 452, 454, and 455 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-16 5-1 Emirates Route Control Destinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-4 5-2 Locations Eligible for Supplemental Destination Signing . . . . . . . . . . . . . . . . . . . . . . . . . .5-5 5-3 Guide Sign Background Color Coding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-6 5-4 Information Eligible for Display on Guide Signs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-7 5-5 Places Not Eligible for Display on Guide Signs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-8 5-6 Recommended “x” Height for Guide Signs (millimeters) . . . . . . . . . . . . . . . . . . . . . . . . .5-11 6-1 Colors of Longitudinal Pavement Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-3 6-2 Use of No Passing Line 611 on Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-7 6-3 Use of No Passing Line 611 and Channelizing Line 612 at Junctions . . . . . . . . . . . . . . . . .6-7 6-4 Lane End Arrows Spacing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-18 6-5 Suggested Maximum Spacing for Highways Delineators on Bends . . . . . . . . . . . . . . . . .6-28 7-1 Location of Roadworks Sign 7441 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-13 7-2 Recommended Cone Spacings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-21 7-3 Warning Arrow Panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-27 9-1 Permissible Sequential Traffic Control Signal Indications . . . . . . . . . . . . . . . . . . . . . . . . . .9-8 9-2 Additional Permissible Sequential Traffic Control Signal Indications During Signal Preemption Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-10 9-3 Required Advanced Visibility of Traffic Control Signal Indications . . . . . . . . . . . . . . . . .9-12 9-4 Minimum Vehicular Volumes for Criterion 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-30 9-5 Minimum Vehicular Volumes for Criterion 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-30 9-6 Minimum Vehicular Volumes for Criterion 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-31 9-7 Minimum Vehicular Volumes for Criterion 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-36 9-8 Vehicle Change Interval (seconds) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-40 9-9 Vehicle Red Clearance Interval (seconds) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-40

Version 0.1

xiv


1

- establish road user right-of-way.

GENERAL PROVISIONS

1.1

•

- indicate potential hazards. - identify major changes in road characteristics. - locate physical obstructions. - inform of regulatory controls ahead. - advise of appropriate actions.

GENERAL

1.1.1 REQUIREMENTS AND PURPOSE OF TRAFFIC CONTROL DEVICES •

The Abu Dhabi Traffic Control Devices Manual establishes the basic guidelines and principles that dictate the design, application, and maintenance of traffic control devices. These devices, including traffic signs, pavement markings, and signals, are placed on, over, or adjacent to a public road and act to regulate, warn, or guide the traffic flow on that facility. In order to fulfill the duty of promoting safe and efficient vehicular movement, a traffic control device should meet these basic requirements: • • • •

establish route identification. direct motorists to destinations. delineate lane assignments. provide general information to motorists.

The requirements and purposes of traffic control devices can be achieved through the proper design, application, placement, maintenance, management, and uniformity, as specified in this manual.

The device should fulfill an important need. The device should command attention. The device should convey a clear, simple meaning. The device should command the respect of motorists. The device should be positioned to give sufficient time for proper response.

1.1.2 STANDARDIZATION OF APPLICATION Traffic control devices applied in predictable ways can significantly improve the safety and operation of roadways. When nonstandard devices are used in nonstandard applications, road users may tend to disregard and disrespect the intended regulations or warnings. The need to standardize traffic control devices in Abu Dhabi has heightened due to the following factors: •

As regulations. As warnings. As guidance.

• •

Therefore, traffic control devices are commonly categorized into three groups with the following specific purposes: •

Guide devices should be used to: -

The basic purpose of traffic control devices is to provide visual information to the motorist. The information is conveyed in three ways to the road user: • • •

Warning devices should be used to:

Road networks are becoming increasingly more complex. Traffic speeds and volumes are increasing. The number of visitors and, therefore, drivers unfamiliar with the city is increasing.

In an effort to standardize the application of traffic control devices, the following objectives must be achieved:

Regulatory devices should be used to:

•

- inform of traffic laws, regulations, and statutes. - instruct to take some physical action. - prohibit certain vehicular maneuvers. - permit certain vehicular maneuvers.

•

1-1

Accuracy: Where the sign face accurately displays a relationship to the road conditions being experienced. Uniformity: Where the sign face, color, legend, symbol, etc., are designed such that the

Version 0.1


• •

motorist can reduce reading and comprehension times whereby the time available to take proper action is maximized. Consistency: Where like situations are signed and marked in a consistent or like manner. Continuity: Where the message is displayed continuously until the information provided is no longer relevant to the circumstances or the road conditions.

signs is recommended to reassure motorists of their location and route.

1.1.5 ADVERTISING SIGNING Any signs or markings placed on the road system not having approval by the Abu Dhabi Municipality should be removed. Any signs or markings advertising or promoting a private company, their products, or services should be prohibited from the public road right of way unless specifically authorized.

1.1.3 APPROVAL FOR PLACEMENT

1.2

Traffic control devices should be placed only with the approval of the Abu Dhabi Municipality for the purpose of regulating, warning, and guiding traffic. The use of traffic control devices in any Municipal or privately owned semipublic area without proper approval should not be permitted.

CLASSIFICATION

1.2.1 ROUTE DESIGNATION A route designation system that includes a range of road classifications has been developed to assist in the consistent application of guidance and information signs. The local and regional road network has been defined by various road classifications, each with a distinct character, purpose, and level of access control. The road classifications in Abu Dhabi are listed and described in Table 1-1.

When given approval by the Abu Dhabi Municipality for the erection of specific devices, construction contractors, public utility companies, and police agencies are permitted to erect construction, maintenance, and other warning signs to protect the public provided that such signs, markings, and devices conform to the standards contained in this manual.

1.2.2 TRAFFIC CONTROL DEVICE CLASSIFICATION

1.1.4 EXCESSIVE USE OF TRAFFIC CONTROL DEVICES

The traffic control devices included in the Abu Dhabi Traffic Control Devices Manual are traffic signs, pavement markings, and signals. Signs, markings, and signals are broadly grouped into three major categories:

Due care should be taken to limit the number of traffic signs and markings used. Regulatory and warning signs should be used conservatively as these signs, if used excessively, tend to lose their effectiveness and road users could disregard their message. However, a frequent display of guide

• • •

Regulatory. Warning. Guide.

Table 1-1 Roadway Types by Functional Classification Roadway Type for Design Roadway Classification Urban Rural Freeway Freeway Primary Expressway Expressway Arterial Arterial (Main Roads) Secondary • Primary Frontage Roads • Secondary Sector Road Collector Local • Primary Local Access • Secondary

Version 0.1

1-2


A fourth group of signs and markings is that of roadworks devices. This group includes all of the three major categories of devices. The categories of typical traffic control devices are defined in Figure 1-1 with subclasses identified for each.

1.3

SCOPE OF APPLICATION

The guidance in this manual is to be practiced on all roads owned and managed by the Abu Dhabi Municipality Road Department. The roads managed by the Department include all roads on Abu Dhabi Island and roads on the mainland in the vicinity of Abu Dhabi Island. In exceptional cases, the Department also constructs and manages road improvements in other areas of Abu Dhabi Emirate. Figure 1-2 is a map showing the general boundaries of the roads owned and managed by the Department in the vicinity of Abu Dhabi.

Typical Traffic Control Devices

Regulatory

Pavement Marking

Signals

• Control • Mandatory • Prohibitory • Parking Control • Freeway Control

Guide

Warning

Signs

Pavement Marking

Signals

Signs

• Advance Warning • Hazard Marker • Diagrammatic Warning

Pavement Marking

Signs

• At-grade Junctions • Grade-separated Junctions • General Information • Route Numbers • Trailblazing

ROADWORKS

Figure 1-1 Classification of Traffic Control Devices

1-3

Version 0.1


Version 0.1

1-4


2

•

TRAFFIC SIGNS — GENERAL

Traffic signs should be installed only when stipulated by the principles of this manual and/or when deemed warranted on the basis of a traffic engineering evaluation. Traffic signs are necessary to advise motorists of traffic regulations that apply at specific locations and/or at specific times and to warn of hazards that may not otherwise be self apparent. Traffic signs also provide motorists with information concerning routes, destinations and locations of interest.

•

•

The standardization of traffic signs in their appearance, placement, and design simplifies the task of road users in finding, recognizing, and understanding signs and markings. It also aids road users, the Traffic Police, and the legal system in having a common interpretation of sign meanings and messages.

•

Other shapes should not be used for sign panel outline shapes unless specifically approved by the Abu Dhabi Municipality Road Department.

The meanings and applications of specific standard traffic signs are described in detail in Chapters 3, 4, 5, and 7 of this manual. This chapter deals with the attributes and criteria of signs in general.

2.1

The RECTANGLE, with the long axis vertical, is used primarily for regulatory signs (primarily parking control and one-way signs). The shape is also used for diagrammatic warning signs and may occasionally be used for guide signs. The TRIANGULAR shape, with the point up, is used exclusively for advance warning signs such as a sign warning a driver of a curve ahead. The RECTANGLE, with the long axis horizontal, is the primary shape for direction and general information guide signs and as supplemental plates or qualification plates below other sign shapes. It is also used for the oneway regulatory sign. The POINTED RECTANGLE, with the long axis horizontal, is used exclusively for chevron signs.

2.1.2 SIZE The size of a traffic sign is important for two primary reasons: •

UNIFORMITY OF ATTRIBUTES

Conspicuousness: A sign must be of sufficient size to command the attention of drivers against the background of the roadway environment. Legibility: The legend (text or symbol) of the sign must be of sufficient size to allow recognition and comprehension by drivers traveling at roadway design speeds.

Uniformity of attributes applies to shape, dimensions, color, legend, conspicuousness, and nighttime visibility of signs. The standardization of these attributes is necessary for an efficient and uniform signing system.

•

2.1.1 SHAPE CODE

For guide signs, which are largely text based, the sign sizes will vary widely depending on the amount of legend and the lettering size of the legend. Legibility is the primary factor controlling guide sign sizes.

Standard sign shapes are as shown in Figure 2-1 and their principal features are listed below: • • •

The OCTAGON shape is reserved exclusively for the STOP sign. The TRIANGULAR shape, with the point down, is reserved exclusively for the GIVE WAY (YIELD) sign. The CIRCULAR shape is reserved exclusively for regulatory signs such as speed limit signs.

Sizing guide signs on the basis of legibility will generally ensure that a guide sign will be conspicuous. The parameters affecting guide sign sizing are discussed fully in Chapter 5 of this manual and therefore are not generalized herein.

2-1

Version 0.1


Reserved exclusively for the STOP sign.

Reserved exclusively for the GIVE WAY (YIELD) sign.

Reserved exclusively for REGULATORY signs (mandatory and prohibitory).

Primarily used for REGULATORY SIGNS. Also used for DIAGRAMMATIC WARNING signs.

Reserved exclusively for ADVANCE WARNING signs.

Primary shape for GUIDE signs including DIRECTION signs and GENERAL INFORMATION signs. Also used for ONE WAY sign and SUPPLEMENTARY PLATE or QUALIFICATION PLATE below other signs.

Reserved exclusively for CHEVRON DIRECTION signs.

Figure 2-1 Standard Sign Shapes

Version 0.1

2-2


For regulatory and warning signs, a standardization of size is possible and is in fact necessary. Regulatory and warning signs, which are more symbol oriented than text oriented, tend to be much smaller in size than guide signs. Because of their relatively small size, conspicuousness is an equally important factor as legibility in sizing regulatory and warning signs.

589 (see Section 5.7.4 of this manual) should accompany these signs for a period of up to three years, if deemed necessary, for public education.

Table 2-2 establishes the background colors, legend colors, and border colors to be used for traffic signs in Abu Dhabi.

Standard text messages in Arabic and English should be used when an appropriate symbol is not available. Symbolic messages given in this manual should be used in preference to text messages whenever available. Otherwise, word messages should be as brief as possible. The Department’s standard Arabic and English fonts should be used for text on all types of signs. The height of the Arabic “aleph” character should be 1.4 times the height of the English “x” letter height. Numerical legends and their corresponding unit of measure should be displayed in English and Arabic except in the specific case of route numbers.

Sign background and legend colors or uses other than those listed in Table 2-2 are not permitted.

2.1.5 RETROREFLECTION AND ILLUMINATION

2.1.4 LEGENDS The legend of a traffic sign is the element that provides a sign with a unique and definitive meaning or message. The legend may be composed of a symbol, a text message, or both.

Traffic signs are generally required to function on an around-the-clock basis. It is thus necessary that they exhibit the same shape and color during both day and night hours. To accomplish this, all sign faces should be constructed using retroreflective sheeting.

Symbols used should be the same in appearance as those shown in this manual. When new symbols are approved for usage, especially on warning signs, a SUPPLEMENTARY PLATE sign

Retroreflective sheeting gains its name from the design characteristic of the sheeting whereby the sheeting is capable of capturing light coming from a vehicle headlight and reflecting a signifi-

Table 2-1 presents guidelines for selecting the appropriate sign sizes for regulatory and warning signs.

2.1.3 COLOR CODE

Operating Speed3 (km/h) 40 60 80 >100

Table 2-1 Regulatory and Warning Sign Sizes1, 2 Recommended Recommended Regulatory Sign Size4, 5 Warning Sign Size6 (millimeter) (millimeter) 600 750 750 900 900 1200 1200 1500

Required Minimum Clear Visibility (meters) 50 60 80 100

Notes: 1. Sizes smaller than the lower limits shall not be used without specific authorization. 2. The sizes for regulatory signs are not applicable to parking control signs and freeway control signs. 3. When it is known that 85th percentile speeds are significantly different from posted speed limits, sign sizes should be chosen based on an 85th percentile speed. 4. Regulatory sign sizes refer to a circle diameter. For the STOP sign, the diameter represents an inscribed circle. 5. Warning sign sizes refer to the apex to apex measurement of the side of the triangular sign. GIVE WAY signs should be sized in the same way as warning signs. 6. Sizes shown are desirable minimums. Larger sign sizes, particularly for warning signs, may be used in particularly critical situations.

2-3

Version 0.1


Table 2-2 Traffic Sign Backgrounds and Legend Colors1 Sign Class Background Color Legend Color

Border Color Regulatory Control Red/Blue White White/None Mandatory Blue White None Prohibitory White Black Red Parking White Red/Green2 Red/Green Freeway control Blue White White Warning White Black3 Red Guide Emirates Routes direction Blue White4 White Abu Dhabi roads direction Blue White4 White Supplemental direction Brown White White Street name signs — local/collector roads5 Blue/Green White Metallic Distance (Emirates Route) Blue White White Parking Blue White White Other Blue White White Roadworks — all signs except regulatory control Yellow Black3 Red/Black Notes: 1. This table provides general information. Exceptions and variations exist in most sign classes. 2. Permissive parking signs also include a white on blue parking symbol. 3. Warning signs may include red in the legend to represent such things as “hazard” areas. Hazard marker signs include red arrow shapes. 4. Route numbers and abbreviations within the route emblem shall be yellow. 5. Street name signs are not covered in this manual. Their standards and installation fall under the authority of other Municipality sections.

cant portion of that light back to the eye of the driver. This reflected light is what drivers see, allowing them to distinguish the shape, color, and ultimately the message of the sign. Since signs must be located outside of the travel path of a vehicle, the nighttime visibility of a sign is dependent upon the ability of the sheeting material to capture light striking the surface of the sign at an angle and reflect that light back at the same angle. This feature, called angularity, is one of the primary measures of the functionality of a retroreflective sheeting material. Type-MP highintensity microprismatic retroreflective sheeting has very favorable properties with respect to angularity and thus should be used for sheeting on all traffic signs of all types described in this manual unless otherwise specifically stated.

spicuousness and legibility. However, this is not usually the case for signs mounted overhead. Overhead signs are generally guide signs containing multiple pieces of information that must be viewed and understood by drivers traveling at relatively high speeds and/or under heavy traffic volumes and/or through complex interchange maneuvers. Thus these signs must be conspicuous and legible from a relatively long distance to provide adequate time for a driver to comprehend the messages being conveyed. Particularly on urban roadways, where driving is done with low beam headlights, the intensity of light from vehicles striking the sign face is too low to provide this long distance legibility. For this reason, all overhead signs should be illuminated except in cases where all of the following conditions are met:

A vehicle directs the largest percentage of its headlight output slightly below horizontal (and predominantly to the right), especially under low-beam operation. Thus, ground-mounted signs (particularly those on the right side of the roadway) will generally be well lit by vehicle headlights and will be capable of retroreflecting enough light to provide adequate nighttime con-

Version 0.1

• •

2-4

When the roadway is not lighted, and When the sign is visible from a distance of 370 meters or more, and


•

•

When the horizontal curvature of the road approaching the sign has no less than a 250 meter radius.

•

The standard means of illuminating overhead signs should be through the use of external illumination using mercury-vapor wide-beam floodlights. Other means of external lighting, internal lighting, or legend-outline lighting will be permitted only on a special case demonstration basis when authorized by the Abu Dhabi Municipality Road Department.

2.2

•

•

Divided roadways and one-way roads where supplementary regulatory, warning, or guide signs are needed. Two-way roadways where sharp right curves exist. Multilane freeways where visibility of rightside signs is blocked (this can also be a warrant for the use of overhead signs, particularly guide signs). At roadworks, particularly for signs located within the advance warning area.

Every sign location must be thoroughly checked to identify any possible visibility obstructions. Typical problem placement locations include:

TRAFFIC SIGN PLACEMENT

• • •

This section deals with the placement of groundmounted and overhead signs. Proper placement of traffic signs refers to the lateral, vertical, and longitudinal positioning that provides the necessary sign legibility for the passing motorists. Without proper placement the efforts to select, design, fabricate, and apply traffic signs are wasted. However, since no two roads are aligned and designed alike, the guidelines for sign placement given here are intended to be interpreted with a measure of flexibility. Sound engineering judgement on an individual project basis, following the general guidelines provided here, must be applied so that sign visibility and legibility are maximized.

• •

Downhill dips in the roadway. Crest vertical curves. Parked or stationary vehicles blocking visibility. Trees and other foliage blocking visibility. Proximity of other (existing) traffic signs in front of or behind the new sign under consideration.

In addition, signs should be placed to avoid blocking or impeding the pedestrian or bicycle flow along sidewalks and trails. While traffic signs are placed to enhance the safety conditions of a roadway, they are fixed obstacles which can pose a hazard if struck by motorists. Therefore, the sign supports must be protected appropriately and the supports themselves should not be overdesigned.

It should never be assumed that a poorly designed roadway can be corrected by providing superior traffic signing. The basic guidelines of sign placement must be considered early in the road design process. This applies particularly to the provision of guide signs and sequences of guide signs on multilane expressways and freeways and even more so to signs required within complex interchanges. Except as identified in this section, all traffic signs should be positioned on the right side of the roadway facing the approaching traffic or overhead close to the center of the travel lanes to which the signs apply. Under certain motoring conditions traffic signs can be placed on the left side of the road. These conditions are:

2.2.1 LATERAL PLACEMENT Since signs are a roadside hazard if struck, they should be placed at as great a distance from the pavement edge as practical. However, the further removed that signs are from the pavement edge the less conspicuous and legible they become to motorists. Every opportunity to position traffic signs behind crash barriers, guardrail, or other roadside safety barriers should be pursued. Figures 2-2 and 2-3 and Table 2-3 describe the requirements for lateral placement of signs.

2-5

Version 0.1


Table 2-3 Lateral and Vertical Positioning of Traffic Signs (refers to Figures 2-2 and 2-3) Roadway Type Dimension Minimum Maximum Remarks (millimeters) (millimeters) Freeway A 600 3000 Expressway B 3600 9000 Major Arterial C 2100 2500 See Notes 5, 6, and 7 Frontage D 1600 2500 See Notes 7, 8, and 9 E 500 1600 See Notes 5, 6, and 8 F 2100 2500 See Note 5 G 6000 See Note 10 H 50 I 600 - See Note 11 J 9000 K 6000 6500 See Note 12 L 1800 4200 See Note 10 Arterial A 300 1000 Collector B 600 2000 Local C 2100 2500 See Notes 5, 6, and 7 D 1900 2500 See Notes 7, 8, and 9 E 1200 1600 See Notes 5, 6, and 8 F 2100 2500 See Note 5 G 6000 See Note 10 I 600 - See Note 11 K 6000 6500 See Note 12 L 1800 4200 See Note 10 NOTES: 1. Dimension letters refer to Figures 2-2 and 2-3. 2. If no dimension value is given in the table this means that the dimension concerned is variable. 3. Lateral dimension reference points are defined as follows: X - Face of curb, guardrail, or barrier. Y - Edge of pavement. Z - Edge of shoulder. 4. For large, multipost signs with a breakaway post system, the minimum clearance between the underside of the sign and the ground below it shall be 2250 millimeters. This will permit a standard vehicle striking the post to pass under the sign panel. 5. In urban areas (assumed to be curbed but may sometimes not have curbs) vertical dimensions are the minimum clearance from the bottom of the sign to the ground below. 6. Certain regulatory signs, principally the mandatory turn signs 322, 323, 326, 327 and 328 are commonly located in front of drivers as they approach a turn. These signs should be mounted as per dimension “E” rather than “C” if so doing will not create a visual obstruction. 7. When two signs of different classes are mounted on the same post a regulatory sign should be mounted above an advance warning sign. 8. In rural areas (assumed to be uncurbed) vertical dimensions are measured up from the near side edge of pavement elevation (Point Y). If the roadway is superelevated such that it rises in the direction of the sign, the pavement surface slope shall be extended to the furthest edge of the sign and the vertical dimension taken from that elevation. 9. The use of a mounting height of less than 2000 millimeters is not recommended for Dimension “D” for signs with a single support unless the support is provided with a breakaway system. 10. The maximum value stated may be exceeded but individual detailed structural designs shall be provided for all support structures. 11. When posts are required to be located behind a flexible beam guardrail, the minimum dimension shall be checked for compatibility with the maximum deflection of the railing being used. 12. The minimum dimension given is the point of minimum clearance between the bottom of the sign support structure and the pavement surface (including shoulder if sign is over shoulder) vertically below. Minimum clearance will be 6.0 meters for gantries and 6.5 meters for cantilevers.

Version 0.1

2-6


Parking Control Signs B

A

A

C

C

X

D Z/Y

X

Detail 2-2-1: Standard Regulatory Signs

B

A

D

D

D Z/Y

X

Detail 2-2-2: Standard Advanced Warning Signs E

A

B E

X

Z

B E

A E

Z

X

Detail 2-2-3: Hazard Warning Signs A

A B

X

Z/Y

E

150 millimeters

X

Detail 2-2-4: Gore Hazard Marker

Detail 2-2-5: Diagrammatic Warning Signs

Figure 2-2 Lateral and Vertical Positioning of Regulatory and Warning Signs

2-7

Version 0.1


0.5 Median Width

A

C

C

A

E

X

X Median

Vertical Community Street Name Detail 2-3-1: Street Name and Action Direction Signs

Lateral

B

A

A

A

D

C Z/Y

X

Z

Gore

Uncurbed

Curbed

E

Z

Detail 2-3-2: Route Marker and Gore Exit Direction Signs

G

G E

B F

X

F

Z/Y

Curbed

Uncurbed

Detail 2-3-3: Guide and General Information Signs

L H I

X

K

J Y

Gantry

K

I X

Cantilever

Detail 2-3-4: Overhead Direction Signs

Figure 2-3 Lateral and Vertical Positioning of Guide and General Information Signs

Version 0.1

2-8


•

2.2.2 VERTICAL PLACEMENT The vertical placement of a traffic sign should be determined as the least distance measured from the pavement or ground surface to the underside of the sign, taking account of cross fall or super elevation if the sign is positioned over the roadway. The mounting height of a traffic sign affects the following elements: • • •

•

The visibility of the sign. Pedestrian hazard of striking the underside of signs. The breakaway safety of the support structure.

•

Figures 2-2 and 2-3 and Table 2-3 describe the requirements for vertical placement of signs.

2.2.3 LONGITUDINAL PLACEMENT Longitudinal placement is the element of sign positioning that is the least definable. Guidelines for the longitudinal placement are general and subject to the specific field and road conditions, particularly in urban areas. The longitudinal placement along a road depends on the sign type, criticality of message, and maneuver required. Traffic sign positions can, and should, be moved longitudinally in many situations in order to: • • • •

• •

Improve visibility. Avoid blocking other signs. Improve roadside safety. Increase spacing between adjacent signs.

As a general guide, regulatory signs are placed where the mandate/prohibition starts or applies. Regulatory signs may commonly be repeated along a section of road to improve driver awareness of the application of the regulations. Warning signs are placed sufficiently far in advance of the condition being indicated on the sign to allow adequate response time to the warning. Guide signs should be placed at regular positions that best guide the motorist to routes and destinations of interest.

• • • •

General guidelines for the longitudinal placement of signs are provided below:

2-9

Most regulatory signs are placed where their message is applied. These sign messages typically refer to one point (e.g., a STOP sign) or remain in effect until another regulatory sign changes the requirement (e.g., a SPEED LIMIT sign). When regulatory signs are located in advance of the point of application of the regulation, an accompanying distance referring to the point of application should be displayed, normally with a SUPPLEMENTARY PLATE sign. Advance warning signs should be provided well in advance of the hazard or condition being signed. The motorist must recognize the message, determine the appropriate response, and adjust his speed accordingly prior to arriving at the hazard. The distance that an advance warning sign is located from the hazard therefore varies with the speed at which the hazard can be safely negotiated and with the speed of approach — the greater the speed reduction required, the greater the longitudinal distance that the sign should be located in advance of the hazard. Table 4-1 in Chapter 4 gives detailed guidelines on these distances. Hazard marker signs should be located as close as possible to the hazard they are marking. Directional guide signs should be provided in advance of intersections, interchanges, and exits to allow the motorist to make the necessary decisions and actions. Detailed guidelines for advance distances and the sequencing order of freeway direction signs are provided in Chapter 5 and are illustrated in Chapter 8. On rural roads, a minimum longitudinal spacing between smaller signs of 75 meters to 80 meters is recommended. On urban roads, a minimum longitudinal spacing between smaller signs of 45 meters to 50 meters is recommended. On rural roads, a longitudinal spacing between larger signs of 150 meters to 300 meters is desirable. On urban roads, a minimum longitudinal spacing between larger signs of 90 meters to 175 meters is desirable.

Version 0.1


•

On freeways, a minimum longitudinal spacing of 200 meters between signs should be adhered to.

or more of the following general conditions are present: •

When there is competition from several signs for space along a road it is generally better practice to increase distances between signs rather than to reduce them in order to solve specific problems. However, when guide signs are involved, great care must be exercised in the vicinity of minor side-road junctions to ensure that confusion is not created as a result of a sign position. It is also often a better solution to a problem of smaller, closely spaced signs to mount the signs on a common support, particularly if, as may be the case with regulatory and warning signs, their messages are associated. In such a case the regulatory sign should be mounted above the warning sign. The minimum clearance requirement must be applied to the lower of the two signs.

• •

• • • • •

All grade separated interchanges through roadways. All roadways with four or more lanes in one direction. All roadways with three or more lanes in one direction and with peak-hour design-year one-way traffic in excess of 1,000 vehicles per hour. Restricted sight distance. High percentage of trucks. High speed traffic. Consistency of sign message location through a series of intersections. Insufficient space for ground-mounted signs.

2.2.5 ORIENTATION ANGLE Ground-mounted traffic signs should be placed at approximate right angles to traffic that must read the message. Specifically, signs located less than 9.0 meters from the edge of pavement should be oriented at 93° to the line of approaching traffic. This slight rotation from true right angle eliminates many of the glare problems that can occur when retroreflective sheeting is used. For signs greater than 9.0 meters from the pavement edge an orientation of 87° to the line of approaching traffic is recommended.

Site and field staff must be trained to recognize potential sign placement problems. They must have the authority initiative, and skill to adjust a sign position from that appearing on a drawing in order to overcome local difficulties without creating an undesirable or unsafe side effect.

2.2.4 OVERHEAD INSTALLATIONS Overhead traffic sign installations may be mounted to road bridges, overcrossing structures, or support structures. The signs placed on overhead structures should be located directly over the affected travel lane(s). Overhead structures and signs are typically provided on freeways, multilane facilities, and heavily traveled roads. Overhead guide signs should be used when one

Figure 2-4 illustrates sign orientation in these two distance conditions.

Greater than 9.0m Edge of pavement

Edge of pavement

Less than 9.0m

93°

Figure 2-4 Sign Orientation Angle Version 0.1

2-10

87°


3

REGULATORY SIGNS

3.1

GENERAL

•

Regulatory signs are used to control the actions of road users. They indicate what road users must do and what they must not do. Failure to obey a regulatory sign, unless directed otherwise by a traffic officer, constitutes an offense. For this reason it is important that those who erect regulatory signs do so with a clear knowledge of other regulatory signs in the vicinity in order to avoid conflicting regulatory messages being presented to road users.

•

It is also possible to add information to a regulatory sign that does not modify its application but simply gives road users additional information about its operation. Examples of such applications are:

Regulatory signs must be easy to understand, difficult to misinterpret, and easy to enforce without argument. To this end symbols are recommended whenever possible rather than words to pass on regulatory messages. The use of exclusive shapes for regulatory signs, such as the octagon for the STOP sign and the inverted triangle for the GIVE WAY sign, together with the reserved use of a circular shape for most other regulatory signs ensures that their function can be instantly recognized by road users.

•

•

The significance or meaning of each individual regulatory sign is given in subsequent sections of this chapter. It should be clearly understood that a regulatory sign applies for 24 hours a day and to all road users approaching the sign. If it is required to modify either or both of these two factors the sign must be altered in some way. This can be achieved by either: • •

If a speed limit is reduced in the vicinity of a school the SPEED LIMIT sign may have a SUPPLEMENTARY PLATE sign 589 indicating SCHOOL. If an advance warning sign is considered necessary before the introduction of a regulatory sign and an appropriate warning sign is not available, a SUPPLEMENTARY PLATE sign 589 may be displayed below the regulatory sign indicating the distance to the start of the regulation. A second regulatory sign, without such a plate, must be placed at the point from which the regulation is to apply.

In order to maintain the clarity of message required of regulatory signs it is recommended that only one symbol should be used on a sign. If two messages are required, two signs should be used.

Qualifying the meaning of the sign with a QUALIFICATION PLATE. Use of a variable message sign.

There are many aspects of the control of road users and of the safe, good behavior of road users which apply throughout the road network. This makes it impractical to exercise the necessary control by means of erecting a large number of regulatory signs.

The use of a QUALIFICATION PLATE below a regulatory sign may qualify the meaning of the sign in any number of ways: •

By showing that a specific class of vehicle is obliged or prohibited from taking some action while the rest of road users are not. For example, a TURN RIGHT ONLY sign required to apply to heavy vehicles but not other traffic should display a plate with the pictogram or symbol of a heavy vehicle below the TURN RIGHT ONLY sign. The only exception to the above rule is the NO U-TURN sign when required to indicate that the sign is applicable to heavy vehicles only. This case is further described in Sections 3.4.3 and 4.2.8.

By indicating the time(s) of the day that the sign is operational. For example, a NO STOPPING sign required to operate only during peak hours should display a plate with the appropriate times of the peak periods indicated below the NO STOPPING sign.

3-1

Version 0.1


•

3.1.1 FUNCTION AND OBJECTIVES OF REGULATORY SIGNS

•

It is the function of regulatory signs to supplement the rules of the road to further control the actions of road users, when necessary, in the sense that road users should take, or not take, specific actions as indicated by such signs.

•

Many of the signs in these classes may also be used at roadworks. The roadworks signs universally use a black symbol on a yellow background with the exception of any control signs used at roadworks which retain the colors shown in the following sections.

It is the function of regulatory signs to indicate the existence of general laws or regulations made in the interests of road safety, such as by SPEED LIMIT signs. Alternatively, regulatory signs may control traffic movement by means of STOP or GIVE WAY signs or traffic signals in the interests of good traffic order and operational efficiency. It can also be the function of a regulatory sign to indicate a change in the general levels of control existing for road users to a different level of control. NO OVERTAKING, NO PARKING, or other restrictions are examples of this.

All classes of regulatory sign apply on a 24-hour basis unless otherwise indicated by a secondary message (see Section 3.1). Signs in all classes may also have a SUPPLEMENTARY PLATE sign 589 located below the regulatory sign. In working with regulatory signs it often helps to consider the way in which the function of an individual sign message is indicated. This function can be considered as exercising control or restriction in one of three ways as follows:

In erecting regulatory signs, the road authority must seek the objective of only providing so many regulatory signs as is necessary, with adequate levels of enforcement, to ensure the safe and orderly movement of traffic. The provision of too many regulatory signs will result in a disrespect for the signing system by road users and a failure to achieve the desired objective.

1. By imposing a restrictive “limit,” e.g., an upper mass limit. 2. By requiring or prohibiting a particular “action,” e.g., a turn. 3. By controlling a particular type of “object” (indicated by a pictogram or symbol of the “object”), e.g., a heavy vehicle.

It should be the objective of any specific regulatory sign to transfer the required message to the intended road users as clearly and as quickly as possible with a minimum effect on the complexity of the driving task. In order to achieve this objective, regulatory signs must be of adequate size and must be correctly positioned to attract the attention of road users.

3.2

3.2.1 STOP SIGN 301 Sign 301 requires that the driver of a vehicle should come to a full and complete stop with such vehicle at the STOP LINE pavement marking 601 and that the driver should not proceed until it is safe to do so.

In order to assist the understanding of the different functions of different types of regulatory sign the class is further subdivided:

•

Control signs assign priority right of way or direction of travel. Mandatory signs indicate actions that must be taken.

Version 0.1

CONTROL SIGNS

The signs in this group have a common function in that they are used to allocate priority right-ofway or direction of movement.

3.1.2 SUBCLASSIFICATION OF REGULATORY SIGNS

•

Prohibitory signs indicate prohibited action or objects. Parking control signs regulate parking and stopping. Freeway control signs indicate limits of roads classified as freeways.

STOP signs should not be used unless engineering judgment indicates that one or more of the following conditions exist:

3-2


STOP signs should not be erected at intersections where traffic control signs are operating. The conflicting commands of two types of control devices are confusing. If traffic is required to stop when the operation of the stop-and-go signals is not warranted, the signals should be put on flashing operation with the red flashing light facing the traffic that must stop. Where two main highways intersect, the STOP sign or signs should normally be posted on the minor street to stop the lesser flow of traffic. Traffic engineering studies, however, may justify a decision to install a STOP sign or signs on the major street, as at a three-way intersection where safety considerations may justify stopping the greater flow of traffic to permit a left-turning movement.

Sign 301

1. Intersection of a less important road with a main road where application of the normal right-of-way rule is unduly hazardous. 2. Street entering a through highway or street. 3. Unsignalized intersection in a signalized area. 4. Other intersections where a combination of high speed, restricted view, and serious accident record indicates a need for control by the STOP sign.

Portable or part-time STOP signs should not be used except for emergency purposes. Also, STOP signs should not be used for speed control. STOP sign 301 should be located on the right side of the intersecting side street between 3 and 15 meters in advance of the near-side edge of the crossroad (see Figure 3-1). A second STOP sign 301 should be similarly located on the left side of the roadway when the side street is a one-way street with two or more lanes, and a central island or median exists.

Prior to the application of these warrants, consideration should be given to less restrictive measures, such as GIVE WAY sign 302 (Section 3.2.2), where a full stop is not necessary at all times. Periodic reviews of existing installations may be desirable to determine whether, because of changed conditions, the use of less restrictive control or no control could accommodate traffic demands safely and more effectively.

A STOP sign 301 should not be used at a junction having a traffic signal or a GIVE WAY sign 302 controlling another approach. STOP sign 301 should have a red background with a white border and white legend.

STOP signs should never be used on the through roadways of expressways. Properly designed expressway interchanges provide for the continuous flow of traffic, making STOP signs unnecessary even on the entering roadways. Where atgrade intersections are temporarily justified for local traffic in sparsely populated areas, STOP signs should be used on the entering roadways to protect the through traffic. STOP signs may also be required at the end of diverging roadways at the intersection with other highways not designed as expressways. In most of these cases, the speeds will not warrant any great increase in the sign sizes.

3.2.2 GIVE WAY (YIELD) SIGN 302 Sign 302 requires that the driver of a vehicle should yield right-of-way at a GIVE WAY pavement marking 602 to all traffic on the roadway intersecting the roadway on which he is traveling, where such traffic is so close as to constitute a danger or potential danger. The driver should also give way to pedestrian and bicycle traffic crossing his path at that point.

3-3

Version 0.1

Centerline


3000 Minimum (See Note 4)

Curb Radius Per Design

300 Minimum 600 Preferred

15000 Maximum

Sign 301/302 (See Note 3) Acceptable Sign Placement Area Envelope (See Note 2)

3000 Maximum

Notes: 1. Dimensions are shown in millimeters. 2. The preferred sign location is a point behind the curbline, within the acceptable sign placement envelope, closest to the stop line unless another position within the envelope gives better visibility of the sign for approaching traffic. 3. Sign orientation should be at right angles to the centerline unless a right turn only is permitted, in which case a radial orientation is required. 4. The 3000 minimum dimension may be increased to 5000 when a conflict with a community street name sign would occur. Figure 3-1 Longitudinal Position of Stop Sign 301 and Give Way Sign 302

The GIVE WAY sign may be warranted:

GIVE WAY sign may be placed at the entrance to the second roadway. 4. Where there is a separate or channelized right-turn lane, without an adequate acceleration lane. 5. At any intersection where a special problems exists and where an engineering study indicates the problem to be susceptible to correction by use of the GIVE WAY sign.

1. At the entrance to an intersection where it is necessary to assign right-of-way and where the safe approach speed on the entrance exceeds 15 kilometers per hour. 2. On the entrance ramp to an expressway where an acceleration lane is not provided. 3. At intersections on a divided highway where the median between the roadways is more than 30 feet wide. At such intersections, a STOP sign may be used at the entrance to the first roadway of the divided highway and a

Version 0.1

GIVE WAY signs generally should not be placed to control the major flow of traffic at an intersection. However, GIVE WAY signs may be installed to control a major traffic movement 3-4


Sign 302

where a majority of drivers in that movement are making right turns. At such an intersection, GIVE WAY signs should not be erected on more than one approach. GIVE WAY signs should not be used on the through roadways of expressways. They may be used on an entering roadway without an adequate acceleration lane, but in a well-designed interchange, the sign would interfere with the free merging movement, and it should not be used under those circumstances.

Sign 303

Sign 303 should be used in conjunction with PEDESTRIAN CROSSING pavement marking 603 and GIVE WAY pavement marking 602. GIVE WAY TO PEDESTRIANS sign 303 should be used in advance of all marked pedestrian crossings which are not otherwise controlled by STOP sign 301, GIVE WAY sign 302 or traffic signals.

GIVE WAY sign 302 should be located on the right side of the intersecting side street between 3 and 15 meters in advance of the near side edge of the crossroad (see Figure 3-1). A second GIVE WAY sign 302 should be similarly located on the left side of the roadway when the street is a one way street with two or more lanes and a central island or median.

A GIVE WAY sign should not be used at at-grade junctions when these are provided with appropriately designed full acceleration lanes.

GIVE WAY TO PEDESTRIANS sign 303 should be located on the right side of the roadway 3 meters in advance of GIVE WAY pavement marking 602. GIVE WAY pavement marking 602 should be at least 3 meters and preferably 6 meters in advance of PEDESTRIAN CROSSING pavement marking 603. A second GIVE WAY TO PEDESTRIANS sign 303 should be provided on the left side of the roadway when a median island or other central island is provided in advance of the pedestrian crossing.

GIVE WAY sign 302 should have a white background with a broad red border.

GIVE WAY TO PEDESTRIANS sign 303 should have the following color pattern:

3.2.3 GIVE WAY TO PEDESTRIANS SIGN 303

•

A GIVE WAY sign should not be used at a junction having a STOP sign controlling another approach.

•

Sign 303 requires that the driver of a vehicle should yield right-of-way to pedestrians crossing the roadway or waiting to cross the roadway. 3-5

The upper, GIVE WAY sign should have a white background with a broad red border. The lower sign, indicating pedestrians, should have a red background with a white icon and border.

Version 0.1


3.2.4 NO ENTRY SIGN 304 Sign 304 indicates to drivers of vehicles that entry is prohibited to all vehicular traffic.

Sign 305

Sign 304

Sign 306

NO ENTRY sign 304 should be used to prohibit “wrong way” entry to a roadway when confusion may exist as to the direction of travel of traffic in the roadway (see Section 3.2.5, ONE WAY signs 305, 306, and 307 ). NO ENTRY sign 304 should be located on the right and left sides of a one-way roadway. NO ENTRY sign 304 should be oriented at 90 degrees to the direction of “wrong way” travel.

Sign 307

travel in streets intersecting the one in which they are traveling is in one direction towards them and to inhibit the possibility of “wrong way” entry to such streets. ONE WAY sign 305 may also be used to indicate that a street is a one-way street in a straight ahead direction (this practice is intended to make drivers aware that when they return to such a street from a private property or a parking area that they must turn only in one direction, it being impractical to indicate the direction of travel at all points of access along a one-way street).

Sign 304 should have a red background with a white legend and a thin white border.

3.2.5 ONE WAY SIGNS 305, 306, AND 307 Signs 305, 306, and 307 indicate to drivers of vehicles that the only permitted direction of travel, in the road or portion of road on which they are erected, is in the direction indicated by the arrow on the sign. Signs 305, 306, and 307 may be displayed to indicate directions straight ahead, to the right, or to the left.

When used to indicate the direction of travel in an intersecting street ONE WAY signs 306 and 307 should be located on both sides of the intersecting street so that both signs can be seen clearly by drivers traveling in the through street. When used to indicate the direction of travel within a one-way roadway ONE WAY sign 305 should be located on the right side of single-lane one-way streets and on both sides of one-way

ONE WAY signs 305, 306, and 307 should be used in preference to NO ENTRY sign 304 in networks of intersecting one-way streets. ONE WAY signs 306 and 307 should be used to indicate to drivers of vehicles that the direction of

Version 0.1

3-6


streets with two or more lanes. If necessary, additional signs should be strategically placed with respect to local accesses from properties or parking areas (see Figure 3-2).

in a street at a junction, other directions of travel at the junction may be chosen. AHEAD ONLY sign 321 indicates that drivers have no other choice but to proceed straight ahead. A 600-millimeter sign 321 may be mounted on the post below a traffic signal when appropriate.

ONE WAY signs 305, 306, and 307 are the one exception to the general color code for the control group of regulatory signs. ONE WAY signs 305, 306, and 307 should have a blue background with a white legend and a thin white border.

A typical example for the use of AHEAD ONLY sign 321 would be at a signal-controlled crossroad intersection with a free right turn and a dedicated left turn lane or lanes separated from the through route by a splitter island. In this instance, if the driver is located in one of the through lanes the AHEAD ONLY movement is the only available option and should be signed accordingly.

NOTE: In some situations, regulatory signs 304, 321 thru 328, 346, and/or 347 may be used in place of or in addition to ONE WAY signs to delineate a one-way road system. Specific approval should be obtained from the Abu Dhabi Municipality Department for one-way system signing.

3.3

AHEAD ONLY sign 321 should have a blue background with a white icon and a thin white border.

MANDATORY SIGNS 3.3.2 TURN RIGHT (OR LEFT) ONLY SIGN 322 (OR 323)

The signs in this group have the function that they are used to indicate to road users actions that they must take or that are mandatory.

Signs 322 (or 323) require that the driver of a vehicle should proceed only to the right (or to the left - the arrow direction being reversed) at the junction. TURN RIGHT (or LEFT) ONLY signs 322 (or 323) should be located on the far side of a roadway facing drivers to which they apply.

3.3.1 AHEAD ONLY SIGN 321 Sign 321 requires that the driver of a vehicle should proceed only straight ahead in the direction indicated by the arrow on the sign.

Signs 322 (and 323) should have a blue background with a white legend and a thin white border.

AHEAD ONLY sign 321 should be located on the right side of a two-way roadway and on the left side of a one-way roadway. The function of the AHEAD ONLY sign 321 differs from that of the ONE WAY sign 305 in that, while the ONE WAY sign may indicate the mandatory direction

3.3.3 TURN RIGHT (OR LEFT) AHEAD ONLY SIGN 324 (OR 325) Signs 324 (or 325) require that the driver of a vehicle should proceed only to the right (or to the left — the arrow direction being reversed) at the junction ahead. TURN RIGHT (or LEFT) AHEAD ONLY signs 324 (or 325) should be located on the right side of a two-way roadway and on the left side of a one-way roadway at a distance of approximately 50 meters from the junction to which it applies. Signs 324 (or 325) should normally only be provided when the alignment of the approach to the junction is such that the layout of the junction is

Sign 321

3-7

Version 0.1


307 347

346 301

301 346

301

301

307

*

*

* Optional subject to traffic volumes

306

*

Access to property or parking

305

305 306

307

346

301 305

301

305 347

See Section 3.2.5 Note

Figure 3-2 Use of One Way Signs 305, 306, and 307 with Signs 346 and 347

Version 0.1

3-8


Sign 322

Sign 325

not readily obvious. A 600-millimeter sign 324 (or 325) may be mounted on the post below a traffic signal where appropriate. Signs 324 (and 325) should have a blue background with a white icon and a thin white border.

3.3.4 PASS EITHER SIDE SIGN 326 Sign 326 indicates to the driver of a vehicle that he may pass to either side of an obstruction in the roadway, such as a traffic island. PASS EITHER SIDE sign 326 should be located on a traffic divider, near the nose of the divider, so that there is a minimum clearance of 300 millimeters between the edges of the divider and the sign. The most common application of sign 326 will be at entrances to collector-distributor roads and road splits.

Sign 323

Sign 326

Sign 324

3-9

Version 0.1


PASS EITHER SIDE signs 326 should have a blue background with a white icon and a thin white border.

3.3.5 KEEP RIGHT (OR LEFT) SIGN 327 (OR 328) Signs 327 (or 328) indicate to the driver of a vehicle that he should pass to the right (or to the left, the arrow direction being reversed) of an obstruction in the roadway. KEEP RIGHT (or LEFT) signs 327 (or 328) should be located as near as possible to the leading edge of the obstruction so that there is at least a clearance of 300 millimeters from the closest path of vehicles. Use of signs 327 (or 328) most commonly applies to traffic islands or refuges in two-way roadways or at the beginning of median island when a single two-way carriageway widens to become a dual carriageway. If such a condition occurs on a vertical curve it may be effective to mount two type 327 (or 328) signs one above the other.

Sign 327

Signs 327 and 328 should have a blue background with a white icon and a thin white border.

3.3.6 ROUNDABOUT SIGN 329 Sign 329 requires that the driver of a vehicle should proceed only in a counterclockwise direction at the roundabout ahead.

Sign 328

ROUNDABOUT sign 329 should be located below GIVE WAY sign 302 in advance of the entry to a roundabout when on the approach concerned, it may not be obvious that the junction ahead is a roundabout. In such circumstances, sign 329 may be used in addition to advance warning ROUNDABOUT AHEAD sign 420. Sign 420 should be located as indicated in Chapter 4. Should mini roundabouts be instituted in Abu Dhabi, sign 329 should be used to direct motorists to operate within the junction in a manner consistent with driving rules for a roundabout. Sign 329

Version 0.1

3-10


3.4.1 MAXIMUM SPEED LIMIT SIGNS

ROUNDABOUT sign 329 should have a blue background with a white icon and a thin white border.

3.4.1.1

MAXIMUM SPEED LIMIT SIGNS 339 TO 344

3.3.7 U-TURN SIGN 330 Signs 339 to 344 prohibit drivers of vehicles from exceeding the maximum speed limit indicated in kilometers per hour by means of a number on such a sign.

Sign 330 notifies the driver of a vehicle that he may make a U-turn.

In Abu Dhabi, the following speed limits should be in effect unless otherwise posted: • • • • • •

MAXIMUM SPEED LIMIT signs 339 to 344 should be provided after the point of access from another roadway or when:

Sign 330

U-TURN sign 330 should be located at the end of the traffic median on the near side of the possible U-turn road configuration. At signalized intersections, it should be attached to the traffic signal post supporting the signals for traffic coming from the opposite direction.

• • •

In Abu Dhabi, U-TURN sign 330 is often used with a NO TRUCKS qualification plate 365 mounted below.

•

U-TURN sign 330 should have a blue background with a white icon and a thin white border.

3.4

30 km/h: School zone. 40 km/h: Selected roadways in areas with a high concentration of pedestrians. 60 km/h: Urban dual carriageway. 80 km/h: Selected roadways with limited access and control. 100 km/h: Rural roads. 120 km/h: Freeways and expressways.

There is a change in speed limit along a specific route. There is a reduction in speed limit between intersecting roadways of like types. The road environment that would be the criterion for the speed limit cannot be easily identified by drivers. The distance between postings exceed those indicated in Table 3-1.

The sign numbers apply as follows: •

PROHIBITORY SIGNS

• • • • •

The signs in this group have the function to indicate to road users actions that they must not take, or which are prohibited. Prohibitions may apply in the form of limits, or to certain actions or objects. Maximum limits such as speed or height limits are indicated in circular signs without a diagonal slash. Prohibitions on actions or objects are indicated in circular signs which include a diagonal slash.

Sign 339: 30 km/h (see Chapter 8 for guidance on use of Sign 339 in school zones). Sign 340: 40 km/h. Sign 341: 60 km/h. Sign 342: 80 km/h. Sign 343: 100 km/h. Sign 344: 120 km/h.

The following guidelines and comments should be considered as being applicable to general or average conditions. Specific circumstances may warrant a variation in application when the prin-

3-11

Version 0.1


Version 0.1

Sign 339

Sign 342

Sign 340

Sign 343

Sign 341

Sign 344

3-12


Situation In Which Sign Is To Be Provided Parking Area or Service Road Urban Single Carriageway Urban Dual Carriageway Rural Roads

Table 3-1 Guidelines for Speed Limit Sign Location Sign Location Warrants For Additional Signs(1) After Point Of Access within 10 meters Not applicable within 50 meters Not applicable - Above 60 km/h(2), 4 km between postings - 60 km/h(2), 2 km between postings within 50 meters - Below 60 km/h(2), 1 km between postings - 100 km/h(2), 10 km between postings within 100 meters - 80 km/h(2), 4 km between postings

Notes: 1. Additional signs should be provided at the rate of one extra sign approximately in the middle of the length of section between “postings” as given in the table. A “posting” represents the initial provision of a MAXIMUM SPEED LIMIT sign in terms of the criteria given above and as illustrated in Figure 3-3. 2. Refers to the maximum speed limit posted on the section of road.

ciples involved should be applied with engineering judgment.

3.4.1.2

When the provision of a MAXIMUM SPEED LIMIT sign is warranted, signs should be located as indicated in Table 3-1. Figure 3-3 illustrates the typical use of MAXIMUM SPEED LIMIT SIGNS 341 to 343.

DUAL SPEED LIMIT SIGN COMBINATIONS AND DUAL MAXIMUM SPEED LIMIT SIGN 345

Many Abu Dhabi roadways have one speed limit for cars and another, lower speed limit for trucks and other heavy vehicles. Signing for these conditions should be done using a dual speed-limit sign combination or with a dual speed limit sign combination complemented by DUAL MAXIMUM SPEED LIMIT sign 345.

A MAXIMUM SPEED LIMIT sign should also be provided when a change in maximum speed limit occurs along a route. It is not uncommon that a decrease in maximum speed limit may be as much as 40 km/h (e.g., from 100 km/h down to 60 km/h). In such a situation, an appropriate MAXIMUM SPEED LIMIT sign should be provided for each 20 km/h decrease in speed limit so that the maximum decrease in speed limit posted at any one time is 20 km/h. The minimum distance between successively decreasing speed limit signs should be 500 meters.

Sign 345 (typical)

It is not necessary to post maximum speed limits on major roads after minor joining access roads, except in the unlikely event that with roads of equal status the one being entered has a lower maximum speed limit than drivers would have reason to expect.

All roadways with dual speed limits should be signed using a sign combination as shown in Figure 3-4. The combination is made up of two maximum speed limit signs mounted on a single pole, one above the other, with a truck qualification plate mounted at the bottom, below the sign indicating the speed limit for trucks. The sign indicating the speed limit for cars should be mounted above the

MAXIMUM SPEED LIMIT signs 339 to 344 should have a white background, a black legend, and a thick red border.

3-13

Version 0.1


Version 0.1

3-14


the guidelines in Table 3-1; DUAL MAXIMUM SPEED LIMIT sign 345 should be added subsequently as deemed useful. When used, DUAL MAXIMUM SPEED LIMIT sign 345 should be evenly interspersed with dual speed limit sign combinations. Good engineering judgement should be exercised in determining the location and frequency of DUAL MAXIMUM SPEED LIMIT sign 345 in a dual speed limit zone, but its frequency should not exceed the guidelines in Table 3-1.

3.4.2 NO LEFT (OR RIGHT) TURN SIGN 346 (OR 347) Signs 346 (or 347) indicate to drivers of vehicles that they should not turn to the left or right, as the case may be, at the junction or entrance where the signs are displayed. Figure 3-4 Dual Speed Limit Sign Combination (typical)

sign indicating the speed limit for trucks and other heavy vehicles. On roadways with dual speed limits, dual speed limit sign combinations should be located as would normal speed limit signs, in accordance with the distances specified in Table 3-1. In some conditions, it may be advantageous to complement dual speed limit sign combinations with DUAL MAXIMUM SPEED LIMIT sign 345. This sign takes the appearance of a typical guide sign in color and shape. However, its large size and the limited information on it precludes the potential for confusion on the part of drivers and clearly emphasizes the respective speed limits of the two different types of vehicles.

Sign 346

DUAL MAXIMUM SPEED LIMIT sign 345 is to be ideally located in wide, open areas adjacent to the roadway. DUAL MAXIMUM SPEED LIMIT sign 345 should be considered a complement to but not a substitute for dual speed limit sign combinations, and thus its placement in a dual speed limit zone should not affect the placement or frequency of dual speed limit sign combinations. Dual speed limit sign combinations should first be correctly positioned according to

Sign 347

3-15

Version 0.1


Signs 346 (or 347) should be located on the side of the roadway towards which the illegal turn would be made, not more than 25 meters in advance of the point where the prohibition applies.

ings or where there is a conflict with pedestrian movements. NO U-TURN sign 348 may be made specific to a time of day by means of a QUALIFICATION PLATE sign 365 mounted below the sign. A 600millimeter sign 348 may be mounted on the post below a traffic signal where appropriate. NO UTURN for specific vehicle types is the one exception to this rule and is further explained in Section 4.2.8.

Signs 346 or 347 should only be used in situations where the left (or right) turn would, under normal circumstances, be expected by drivers to be available. Their use is generally not necessary when roadway geometry clearly indicates that turns are not intended at the location under consideration. A 600 millimeter sign 346 (or 347) may be mounted on the post below a traffic signal where appropriate.

NO U-TURN sign 348 should have a white background, a black icon, a thick red diagonal line, and a thick red border.

3.4.4 NO OVERTAKING SIGN 349

Signs 346 and 347 should have a white background, a black icon, a thick red diagonal line, and a thick red border.

Sign 349 prohibits the driver of a vehicle from overtaking another vehicle traveling in the same direction within the next 500 meters.

3.4.3 NO U-TURN SIGN 348 Sign 348 indicates to drivers of vehicles that they should not perform a U-turn at the junction or break in the median island ahead.

Sign 349

NO OVERTAKING sign 349 may be used in addition to NO PASSING LINE pavement marking 611 when this is likely to be ineffective due to adverse conditions or other factors. Sign 349 should be located on the left side of the road. If the overtaking message is required for a distance in excess of 500 meters the sign should be repeated at 500 meter intervals.

Sign 348

NO U-TURN sign 348 should be located not more than 25 meters in advance of the point to which the prohibition applies. The sign may be repeated at the point of prohibition.

NO OVERTAKING sign 348 should have a white background, a black icon, a thick red diagonal line, and a thick red border.

Sign 348 may be required when the parallel carriageway is too narrow to accept safe U-turns or when such a movement cannot safely be accommodated due to limitations in traffic signal tim-

Version 0.1

3-16


3.4.5 NO INFLAMMABLE GOODS SIGN 350

3.4.6 NO GOODS VEHICLES SIGN 351

Sign 350 prohibits the driver of a vehicle transporting inflammable goods, including inflammable gases in portable cylinders, from proceeding beyond the sign.

Sign 351 prohibits drivers of goods vehicles from proceeding beyond the sign.

Sign 351 Sign 350

NO GOODS VEHICLES sign 351 should be located on the right side of the roadway at the point from which the prohibition is required to apply. This point should be chosen where an alternative route is available to drivers of goods vehicles.

NO INFLAMMABLE GOODS sign 350 may be used in advance of any area, such as a tunnel, where transported inflammable goods represent a particular hazard. The sign should be located on the right of the roadway at the point from which the prohibition is required to apply. This position should permit vehicles carrying inflammable goods to take an alternative route. In practice it is likely that other prohibitions may apply at such places. It is recommended that all necessary prohibitory signs be displayed on a custom designed backing board with a white background color and a thin red border of the style used for diagrammatic warning signs. It is also recommended that a similar combined sign be displayed in advance of the exit or turn onto the alternative route with an appropriate explanatory text message such as “Alternative Route 150 m.”

NO GOODS VEHICLES sign 351 may be made specific to a particular time of day rather than for the full 24-hours by means of a QUALIFICATION PLATE sign 365, indicating the applicable time period or periods, mounted below the sign. In a similar way the NO GOODS VEHICLES sign 351 may be made applicable to goods vehicles exceeding a specific weight by the mounting of QUALIFICATION PLATE below the sign which displays the weight limit in the form “10 T” where the unit “T” refers to a metric tonne. Where appropriate this weight limit may be replaced by a length limit such as “6.0 m.” NO GOODS VEHICLES sign 351 should have a white background, a black icon, a thick red diagonal line, and a thick red border.

NO INFLAMMABLE GOODS sign 350 should have a white background, a black icon, a thick red diagonal line, and a thick red border. The detail of the flame within the truck icon on the legend should be red and yellow.

3.4.7 NO PEDESTRIANS SIGN 352 Sign 352 prohibits pedestrians from proceeding beyond the sign.

3-17

Version 0.1


NO CYCLISTS sign 353 may be displayed in any position where it is required to prohibit cyclist movement or access. If pedestrian movement or access is not otherwise prohibited, cyclists may proceed provided they dismount and walk their bicycles. Sign 353 should be used with a size of 300 millimeters unless a larger size is warranted for conspicuousness. Sign 353 should have a white background, a black icon, a thick red diagonal line, and a thick red border.

3.4.9 NO HORNS SIGN 354

Sign 352

Sign 354 prohibits the driver of a vehicle from sounding the horn or other audible device of his vehicle within 75 meters of the sign.

NO PEDESTRIANS sign 352 may be displayed in any position where it is required to prohibit pedestrian movement or access, normally across a roadway. Such places may include specific parts of a roadway or junction which pedestrians otherwise might expect to be able to use, but which are considered unsafe due to the traffic management arrangements of the road or junction. Sign 352 should be used with a size of 300 millimeters unless a larger size is warranted for conspicuousness. NO PEDESTRIANS sign 352 should have a white background, a black icon, a thick red diagonal line, and a thick red border.

Sign 354

3.4.8 NO CYCLISTS SIGN 353 Sign 353 prohibits cyclists from proceeding beyond the sign.

NO HORNS sign 354 may be used in the vicinity of hospitals or other places where it is considered necessary to limit traffic noise. Sign 354 should be located on the right side of the roadway at the point where the prohibition is required to apply. Additional signs may be placed at 150 meter intervals if the prohibition is required over some distance. Sign 352 should have a white background, a black icon, a thick red diagonal line, and a thick red border.

Sign 353

Version 0.1

3-18


3.4.10 MAXIMUM HEIGHT LIMIT SIGN 355

3.4.11 MAXIMUM HEIGHT LIMIT SIGN 356

Sign 355 prohibits drivers of vehicles exceeding the indicated height from proceeding beyond the sign.

Sign 356 incorporates sign 355 into a larger sign and includes an iconic symbol and text to increase visibility and reinforce the sign’s message.

Sign 356 Sign 355

MAXIMUM HEIGHT LIMIT sign 356 should be used only where vehicles exceeding Abu Dhabi’s legal vehicle height limit may use the road on an exceptional basis. It should be placed where it is deemed tall truck traffic may enter the highway. It should be located on both the right and left sides of the roadway.

MAXIMUM HEIGHT LIMIT sign 355 should be located 25 to 50 meters in advance of any limited height structure that has a minimum clearance of less than 4.2 meters, preferably on both the right and left sides of the approach roadway. The height indicated within the sign should be at least 100 millimeters less than the actual minimum clearance measured under the structure. The height should be expressed on the sign to the next lowest one decimal place of a meter.

The height indicated within the sign should be at least 100 millimeters less than the actual minimum clearance measured under the structure. The height should be expressed on the sign to the next lowest one decimal place of a meter.

The maximum legal height for a vehicle in Abu Dhabi is 4.2 meters.

MAXIMUM HEIGHT LIMIT sign 356 should have a white background, a black border, and a black and red legend.

Sign 355 must not be used as an advance warning sign. The sign should always be preceded by an advance warning MAXIMUM HEADROOM sign 425 (see Chapter 4).

3.4.12 QUALIFICATION PLATE SIGN 365

Sign 355-4.2 should be located on both sides of the road at all Emirates Route border crossings into Abu Dhabi Emirate and on all exit roads from cargo-handling seaports.

Sign 365 provides a secondary message that qualifies or restricts the primary message of another regulatory sign. Sign 365 is never used alone and is always mounted directly below the regulatory sign that it qualifies. The background color, border color, and message color of sign 365 should correspond to those of the associated regulatory

MAXIMUM HEIGHT LIMIT sign 355 should have a white background, a black legend, and a thick red border.

3-19

Version 0.1


Thus, a QUALIFICATION PLATE sign 365 may contain textual messages or symbols such as, but not limited to, the following: • • • • •

08:00 TO 20:00. 8 m. Except Friday. Truck (symbol). 10 T.

When it is desired to add to a regulatory sign information that does not qualify the message of the sign, a SUPPLEMENTARY PLATE sign 589 should be used.

3.5

PARKING CONTROL SIGNS

The signs in this group apply to the control and regulation of stopping and parking. The signs in the group are available to clarify stopping or parking controls in complex environments or to indicate circumstances where limited or part-time restrictions operate for part(s) of a day or apply to specific classes of vehicle. The group includes circular prohibition signs, which are commonly contained within a rectangular background. The prohibitory meaning of the sign is not affected by its manner of display. The reason for placing the sign within a rectangular background is to provide a suitable base to display relevant secondary information which limits the application of the sign in some way. Parking control signs may be prohibitory signs or permissive signs. Prohibitory parking control signs use a red border, text, and arrow whereas permissive parking signs, which may still contain a restrictive element in their message (e.g., a maximum duration of stay), use a green border, text and arrow. Prohibitory and permissive parking control signs may be mounted side-by-side on sections of street where a stopping or parking prohibition changes to permitted parking. If there are no time or payment controls over the use of a parking area it is not necessary to erect parking control signs.

Sign 365

sign with which it is mounted (this also applies to roadworks versions of regulatory signs). Ordinarily, regulatory signs apply 24 hours a day, 7 days a week and are relevant to all vehicles passing that sign. QUALIFICATION PLATE sign 365 is used when the regulatory message is intended to apply to only certain times or days, and/or to only certain types or classes of vehicles.

Version 0.1

Not all numbered signs are illustrated. Examples are shown in Figures 3-5 to 3-8.

3-20


3.5.1 NO STOPPING SIGNS 370, 371, 372, AND 373

when a particular stopping problem has been identified.

Sign 370 prohibits the driver of a vehicle from stopping his vehicle at any time along the section of road beyond such a sign, subject to compliance with a traffic signal, the direction of a traffic officer, or to avoid a collision. The action of NO STOPPING sign 370 should cease automatically when a driver leaves the roadway on which it is provided unless he comes under the control of another NO STOPPING sign on the roadway which he enters.

QUALIFICATION PLATE sign 365 should be used to convey regulatory limits with messages such as the following: • • • •

Signs 371, 372 and 373 require that the driver of a vehicle should not stop his vehicle at any time along a section of road within 40 meters of such a sign, subject to compliance with a traffic signal, the direction of a traffic officer, or to avoid a collision. Signs 371, 372, and 373 should include an arrow to indicate the direction of application of the restriction from the sign.

The use of NO STOPPING sign 370 is appropriate on high speed roads such as major arterials which have limited points of access. Sign 370 should be located on the right side of such multilane one-way roadways within 150 meters of a point of entry to the roadway and in such a way that the sign is at right angles to the normal direction of travel.

NO STOPPING signs 371, 372, and 373 should be located on the right and/or left side of the roadway, as appropriate, with the sign face parallel to the curbline or edge of roadway. The maximum distance between signs to give adequate coverage to a full section of nonarterial urban roadway should be 80 meters. When a stopping prohibition is to be applied to a section of roadway for a distance less than 80 meters two NO STOPPING signs 371 and 373 should be used, one at each end of the section of roadway. The range of arrow variations with signs 371, 372, and 373 is illustrated in Figure 3-5.

NO STOPPING sign 370 should not be used indiscriminately but should be limited to situations where: • • •

The stopping of vehicles will pose a severe safety or capacity problem, and There is a situation whereby a significant number of drivers are stopping their vehicles, and Where another form of regulatory sign or pavement marking would not otherwise make stopping illegal.

NO STOPPING signs 371, 372, and 373 may be made specific to a particular time of day, rather than the full 24 hours, by indicating within the

Thus, the use of sign 370 should generally not be included in new designs, but rather as a retrofit

Sign 370

For 1000 m. On Bridge. In Thru Lanes. End.

Sign 371

Sign 372

Sign 373

Figure 3-5 No Stopping Sign Variants

3-21

Version 0.1


sign face the applicable time period or time periods. Alternatives, with their specific sign numbers, are illustrated in Figure 3-6.

to a full section of urban roadway should be 80 meters. When a parking prohibition is to be applied to a section of roadway for a distance less than 80 meters two NO PARKING signs 377 and 379 should be used, one at each end of the section of roadway.

3.5.2 NO PARKING SIGNS 377, 378, AND 379

NO PARKING signs 377, 378, and 379 may be made specific to a particular time of day, rather than the full 24 hours, by indicating within the sign face the applicable time period or time periods. The manner of display should be as illustrated in Figure 3-6, with the substitution of the NO PARKING disc for the NO STOPPING disc and the use of specific sign numbers 380, 381 and 382.

Signs 377, 378, and 379 require that the driver of a vehicle should not park his vehicle at any time along a section of road within 40 meters of such a sign. Signs 377, 378, and 379 should include an arrow to indicate the direction of application of the restriction from the sign. NO PARKING signs 377, 378, and 379 should be located on the right and/or left side of the roadway, as appropriate, with the sign face parallel to the curbline or edge of roadway. The maximum distance between signs to give adequate coverage

:

:

Sign 374

Sign 377

The range of arrow variations with signs 377, 378, and 379 is illustrated in Figure 3-7.

:

:

Sign 375 Figure 3-6 No Stopping with Time Limit Displays

Sign 378 Figure 3-7 No Parking Sign Variants

Version 0.1

3-22

: :

: :

Sign 376

Sign 379


3.5.3 PAY-AND-DISPLAY PARKING SIGNS 383, 384, AND 385

The range of PAY AND DISPLAY PARKING signs 383, 384, and 385 is illustrated in Figure 3-8.

Signs 383, 384, and 385 indicate to drivers of vehicles using the parking area designated by the sign that they should pay the appropriate tariff at the designated payment point and should affix the ticket/notice received on the inside of the windscreen of the vehicle so that it can be observed from outside the vehicle.

3.5.4 PARKING FOR DISABLED PERSONS SIGNS 386, 387, AND 388 Signs 386, 387,and 388 indicate to drivers of vehicles that the parking area designated by the sign is reserved for use by disabled persons only and that it should not be used by other drivers.

PAY-AND-DISPLAY PARKING signs 383 and 385 should be located at each end of a row of parking bays served by a “PAY-AND-DISPLAY” payment point, with the sign face parallel to the curbline or edge of roadway. The arrows on the signs will indicate the point from which the “PAY-AND-DISPLAY” criteria applies, and will generally point towards the payment point. PAYAND-DISPLAY PARKING sign 384 should be located at intermediate intervals between PAYAND-DISPLAY PARKING signs 383 and 385 only when the row of parking bays is considered to be of sufficient length as to warrant the provision of additional “PAY-AND-DISPLAY” payment points. If it is necessary to advise drivers of time limits applicable to the parking area this should be done using appropriate PARKING TIME LIMIT signs 389, 390, and 391 in addition to signs 383, 384, and 385 in a manner similar to the examples in Figure 3-11.

Sign 383

When a single PARKING FOR DISABLED PERSONS sign 387 is required for a single parking bay it should be located on the sidewalk approximately in the center of the length or width of the parking bay. In such an application the arrow is omitted. In other applications, signs 386 and 388 should be displayed in a similar manner to that described for NO PARKING signs 377 and 379 (see Section 3.5.2). Sign 387 should be used only to identify a single parking bay. The range of PARKING FOR DISABLED PERSONS signs 386, 387, and 388 is illustrated in Figure 3-9.

3.5.5 PARKING TIME LIMIT SIGNS 389, 390, AND 391 Signs 389, 390, and 391 indicate to drivers of vehicles using the parking area designated by the

Sign 384

Sign 385

Figure 3-8 Pay and Display Parking Sign Variants

3-23

Version 0.1


Sign 386

Sign 387

Sign 388

Figure 3-9 Parking for Disabled Persons Sign Variants

sign that there are time limits to their use of the parking area. The time limit may apply in one or both of two ways:

STOPPING signs 374, 375, and 376 and NO PARKING signs 377, 378, and 379 with regard to position and frequency. In an area where mixed prohibition (signs 377, 378, and 379) and permissive (signs 383 to 391) signs are used prohibition and permissive signs may be mounted next to each other with arrows pointing in appropriate directions.

• To the maximum duration of the parking period. • To the times of day that parking is permitted. Signs 389, 390, and 391 should include an arrow to indicate the direction of application of the time restrictions indicated on the sign (see Figure 3-10).

The messages of the PARKING TIME LIMIT signs 389, 390, and 391 may be varied. The duration of stay limit or the time of day limit may be omitted if one or other is not appropriate to the circumstances of the parking area.

PARKING TIME LIMIT signs 389, 390, and 391 should be displayed in the same manner as NO

Sign 389

Sign 390 Figure 3-10 Parking Time Limit Sign Variants

Version 0.1

3-24

Sign 391


Figure 3-11 illustrates some of the sign combinations possible within this group of signs.

3.5.6 BUS STOP SIGN 392 Sign 392 indicates to drivers that the section of roadway designated is reserved for the stopping or standing of buses. BUS STOP sign 392 should be located at the edge of the sidewalk so that it can be seen by pedestrians and bus drivers (mounted perpendicular to the curb). It should be positioned near the end of the loading area and indicate the position for the driver to stop and passengers to queue. Sign 392

BUS STOP sign 392 should have a white background. The icon should be offset on a blue background and the horizontal dividing lines should be blue. Both Arabic and English text should be red.

The space reserved by TAXI STAND sign 393 should not be used for the unattended parking of taxis. Taxis may only stand in the space while waiting for fares.

3.5.7 TAXI STAND SIGN 393 Taxi stand locations must be approved by the Traffic Police.

Sign 393 indicates to drivers of vehicles that the section of roadway designated is reserved for the stopping or standing of taxis only, and that such section of road should not be used by other vehicles.

TAXI STAND sign 393 should have a white background. The icon and the horizontal dividing lines should be blue. The border and the Arabic and English text should be red.

Sign 380

Sign 381

Sign 390

Sign 381

Sign 388

Sign 389

Sign 382

Sign 391

Sign 371

Figure 3-11 Examples of Sign Combinations in the Parking Group

3-25

Version 0.1


DROP-OFF PICK-UP ONLY sign 394 should have a white background. The car-and-person icon and the horizontal dividing lines should be blue. The border, the prohibition icon, and the Arabic and English text should be red.

3.6

FREEWAY CONTROL SIGNS

The signs in this group indicate to road users which roads are classified as freeways. In doing so they make road users aware of the application, and removal, of the particular “Rules of the Road” relevant to the use of freeways.

3.6.1 BEGINNING OF FREEWAY SIGN 398

Sign 393

3.5.8 DROP-OFF PICK-UP ONLY SIGN 394

Sign 398 indicates to drivers of vehicles that a dual carriageway freeway begins and that the various controls and prohibitions become effective beyond the sign.

Sign 394 indicates to drivers of vehicles that the section of roadway designated is reserved for dropping off or picking up passengers. These sections of roadways may be used by any type vehicle, public or private.

Sign 398

Freeway rules invoked by sign 398 should mean that, except in case of emergency, no person should:

Sign 394

The space reserved by sign 394 should not be used for the unattended parking of any vehicle. Sign 394 is also generally used near the beginning of the loading area at bus stops, allowing other vehicles to use the bus stop for drop-off and pick-up. Approval should be obtained from the Road Department before installing Sign 394 in a bus stop.

Version 0.1

• • • • •

3-26

Operate a nonmotorized vehicle on or near the freeway. Be on foot on or near the freeway. Stop or reverse a vehicle on the roadway. Stop, park, or drive on a shoulder, median, or roadside area. Drive at a speed less than 70 km/h or 30 km/h less than the prevailing traffic speed, whichever is lower.


The BEGINNING OF FREEWAY sign 398 should be located on the right side within the first third of the length of all freeway on-ramps and on the right side, and left side when a median island is available, when a non-freeway roadway becomes a freeway in a straight-ahead situation. Sign 398 should have a blue background with a white icon and border.

3.6.2 END OF FREEWAY SIGN 399 Sign 399 indicates to the drivers of vehicles that a freeway is about to end and that the relevant freeway rules are no longer applicable.

Sign 399

END OF FREEWAY sign 399 should be located on the right side within the final third of the length of all freeway off-ramps. When a freeway ends, but continues as a non-freeway road, sign 399 should be located on the right side, and if a median island is available, on the left side of the roadway. It should be noted that if it is required that some of the prohibitions provided for on the freeway be retained, specific prohibition signs should be erected accordingly beyond sign 399. END OF FREEWAY sign 399 should have a blue background with a white icon and border. The diagonal slash should be red.

3-27

Version 0.1


4

WARNING SIGNS

4.1

GENERAL

guidelines for the positioning of advance warning signs. Distances in Table 4-1 are based on standard traffic-engineering stopping-sight distance equations (distance needed to reduce speed from approach speed to safe operating speed at hazard).

Warning signs are used to make drivers aware of hazardous or potentially hazardous conditions in the roadway which drivers might not otherwise expect to see due to the nature of the hazard, the hazard being hidden or partially hidden, or due to the driver’s workload at the time. Advance warning signs have a unique triangular shape and the warning message is given in the majority of instances by a symbolic representation of the hazard or potential hazard.

It is also important that there be an adequate clear visibility distance to the warning sign. The availability of this distance must be checked at the time of installation of the sign. Clear visibility distance cannot be assumed to exist simply because it appears to be available from reading a plan of a section of road. Engineers need to exercise professional judgement on site to ensure drivers have adequate clear visibility to a warning sign.

In order to maintain the credibility of warning signs they should only be used when a need has been established or a warrant satisfied. If warning signs are used automatically to “warn” of fully visible everyday road features, those warning signs which really are important are likely to be less effective.

Likewise, sound engineering judgement is required for placement of warning signs used to alert drivers to temporary road conditions or particularly hazardous conditions. In either of these situations, distances from the sign to the hazard may need to be increased or decreased from the guidelines in Table 4-1. It may also be the case that multiple warning signs are needed to effectively alert drivers to a single hazard. Engineers should consider either of these options during initial installation and prepared to review this decision in the future if deemed warranted.

Most warning signs are located in advance of the hazard to which they refer. To be effective as a class, warning signs must be positioned consistently. The location of warning signs should, in part, be related to the speed with which the hazard can be negotiated. This in turn relates to the difference between the speed at the hazard and the speed when viewing the sign. Table 4-1 gives

Approach Speed (km/h)

Table 4-1 Guidelines for Positioning Advance Warning Signs Posted Speed at Hazard (km/h) <20 30 40 50 60 70 Preferred Distance of Sign from Hazard (meters) Note 1 Note 2 25 Note 1 Note 2 75 60 Note 1 Note 2 125 110 100 50 Note 2 150 140 125 110 50 Note 2 175 160 150 125 100 60 200 185 175 150 140 75 250 230 200 180 175 125 275 250 225 210 190 160 300 275 250 230 210 190

80

30 40 50 60 70 80 Note 2 90 65 100 100 110 130 120 175 NOTES: 1. No suggested minimum distances are provided for these speeds, as placement location is dependent on site conditions and other signing to provide an adequate advance warning for the driver. 2. No specific recommended placement distance are provided for these speeds. The Engineer should exercise professional engineering judgement in light of local conditions.

4-1

Version 0.1


The function of each individual warning sign is given in subsequent sections of this chapter. If a warning sign is required for which there is no symbol GENERAL WARNING sign 450 should be used in conjunction with a SUPPLEMENTARY PLATE sign 589 (see Section 4.2.26). SUPPLEMENTARY PLATE sign 589 may be attached below an advance warning sign to enhance the message of the sign (see Section 5.7.4).

which they relate. Consistent with this function they have a unique triangular shape in order to attract the attention of drivers sufficiently early for their message to be effective. Advance warning signs are therefore not appropriate to mark or identify the point location of the hazard. Hazard marker signs should be used for such a purpose (see Section 4.3).

4.2.1 JUNCTION AHEAD SIGNS 401 TO 406

4.1.1 FUNCTION AND OBJECTIVES OF WARNING SIGNS

Signs 401 to 406 warn drivers of vehicles of a junction ahead.

It is the function of warning signs to alert drivers to hazardous or potentially hazardous conditions on or adjacent to the roadway. This function may be exercised in the form of an advance warning of a hazard ahead or by marking the actual physical hazard.

CROSSROAD AHEAD sign 401, SIDE ROAD AHEAD signs 403 and 404 and STAGGERED SIDE ROAD AHEAD signs 405 and 406 are specifically for use on a major road to indicate the presence and layout of the junction ahead. TJUNCTION AHEAD sign 402 may be used on a major or minor road although its use on major roads is not likely to be common.

The objective of warning signs is to transfer the desired warning message to road users as clearly and as quickly as possible with a minimum impact on the driving task and in so doing to create the safest practical road environment for users. In order to achieve this objective warning signs must be of adequate size and must be correctly positioned to attract the attention of road users in time for them to take the required action. By providing warning signs the design engineer must have as an objective the creation of an adequate level of road safety while using the fewest possible signs.

Signs 401 to 406 should be located on the right side of the roadway at a distance from the junction as indicated in Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 indicating the distance to the junction to the nearest 20 meters should be attached below all signs 401 to 406. Signs 401 to 406 should be considered for use in an urban area only when all of the following conditions apply:

4.1.2 SUBCLASSIFICATION OF WARNING SIGNS

• • •

In order to clarify the different functions of warning signs the class is further subdivided as follows: • • •

Advance warning signs. Hazard marker signs. Diagrammatic signs.

4.2

•

ADVANCE WARNING SIGNS

Signs 405 and 406 should only be used when the distance between the staggered side roads is less

The signs in this group should all be used in advance of the hazard or potential hazard to Version 0.1

The junction is not controlled by traffic signals. There are no advance direction signs. With the exception of T-JUNCTION AHEAD sign 402, there are no STOP or GIVE WAY signs or road markings on the major road approach. No other means is available to improve the identification of the junction from an adequate distance to allow drivers to safely negotiate a turn. That is,there are no road markings, gore signing, or street name signs.

4-2


Sign 401

Sign 402

Sign 403

Sign 404

Sign 405

Sign 406

4-3

Version 0.1


than that given in Table 4-2. If the distance exceeds the value shown, two type 403 or 404 signs should be used, the signs being located in accordance with Table 4-1. STAGGERED JUNCTION AHEAD signs 405 and 406 should be located at the distance given in Table 4-1 in advance of the first of the two side road junctions. Table 4-2 Junction Spacing Requirements for Signs 405 and 406 Operating Speed Distance Between (8th Percentile) Junctions (km/h) (meters) Up to 45 <60 45 to 65 <150 65 to 85 <200 <300 $85

Sign 407

It is also appropriate to consider the use of CROSSROAD AHEAD sign 401 and T-JUNCTION AHEAD sign 402 on the minor road approach to a rural junction, particularly if the road alignment is not straight on the approach to the junction. For such an application the width of both legs of the symbol on CROSSROAD AHEAD sign 401 should be sized similarly to that for T-JUNCTION AHEAD sign 402. Signs 401 to 406 should have a white background, a black icon, and a thick red border.

Sign 408

4.2.2 NO THROUGH ROAD SIGNS 407, 408, AND 409 Signs 407 to 409 are to warn drivers of vehicles that the road indicated on the sign is not available to through traffic, i.e., the road is a dead-end road or is closed to through traffic for some reason. NO THROUGH ROAD signs 407 to 409 should be located on the right side of the roadway at a distance from the junction as indicated in Table 4-1 and with a clear sight distance. Sign 409

Signs 407 to 409 should only be used when it is not otherwise obvious that the road concerned is not a through road. The use of sign 409 is appropriate in advance of a crossroad when the straight ahead leg of the junction is not a through road.

Version 0.1

NO THROUGH ROAD signs 407, 408, and 409 should have a white background and a thick red border. The icon should be black and red, with black representing the road and a red “stump” representing the end of the throughway.

4-4


4.2.3 MERGING TRAFFIC SIGNS 410 AND 411

Sign 411 need only be used when the angle between the two merging roadways makes it difficult to position sign 410 so that it may be viewed from both roadways. Signs 410 and 411 should not be used if the traffic on the joining roadway is subject to stop or give way control.

Signs 410 and 411 are to warn drivers of vehicles of a junction ahead where two streams of traffic traveling in the same direction, and of equal priority, are required to merge into one stream.

MERGING TRAFFIC signs 410 and 411 should have a white background, a black icon, and a thick red border.

4.2.4 RIGHT (OR LEFT) CURVE SIGN 412 (OR 413) Signs 412 and 413 warn drivers of vehicles that there is a curve in the road ahead to the right (or left) which requires caution. RIGHT CURVE sign 412 should be located on the right side of the roadway at a distance from the start of a right-hand curve as indicated in Sign 410

Sign 412 Sign 411

MERGING TRAFFIC sign 410 should be located on the right side of the through roadway at a distance from the junction of the roadways as indicated in Table 4-1, subject to adequate clear sight distance being available. MERGING TRAFFIC sign 411, if required, should be located on the right side of the joining roadway at a distance from the junction of the roadways as indicated in Table 4-1, subject to adequate clear sight distance being available. Sign 413

4-5

Version 0.1


Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 indicating the recommended speed at which the curve may be safely negotiated should be attached below sign 412. Sign 413 should be used similarly for a left-hand curve. RIGHT (or LEFT) CURVE sign 412 (or 413) should be used in advance of a horizontal curve that can only be negotiated comfortably by reducing speed by one tenth or more of the operating speed of traffic on the preceding straight. Sign 412 (or 413) should not be used on roadways with a basic posted speed less than 60 kilometers per hour, except for exceptional circumstances.

Sign 414

RIGHT (OR LEFT) CURVE sign 412 (or 413) should have a white background, a black icon, and a thick red border.

4.2.5 BENDS AHEAD SIGNS 414 AND 415 Signs 414 and 415 warn drivers of vehicles that there are sharp reverse direction curves in the road ahead. BENDS AHEAD signs 414 and 415 should be located on the right side of the roadway at a distance from the start of the first curve as indicated in Table 4-1 and with a clear sight distance. A SUPPLEMENTARY PLATE sign 589 indicating the recommended speed at which the curves may be safely negotiated should be attached below signs 414 and 415. The symbol direction must always be specified so that it is correctly oriented for the first curve or bend to be entered, e.g., left before right (414) or right before left (415).

Sign 415

BENDS AHEAD signs 414 and 415 should have a white background, a black icon, and a thick red border.

4.2.6 TWO-WAY TRAFFIC SIGN 416 Sign 416 warns drivers of vehicles in a one way roadway that the roadway ahead carries traffic in both directions.

BENDS AHEAD signs 414 and 415 should only be displayed when: •

• •

TWO-WAY TRAFFIC sign 416 should be located on the left side of a one way roadway at a distance from the start of the two way roadway as indicated in Table 4-1 and with a clear sight distance to the sign. A second sign 416 may be mounted on the right side of the roadway for additional emphasis. A SUPPLEMENTARY PLATE sign 589 indicating the distance to the start of two-way traffic may be attached below

The bends can only be negotiated comfortably by reducing speed by more than one tenth of the operating speed of traffic on the preceding straight, and/or The length of the straight between curves is less than 120 meters, or The nature of the reverse curves is not obvious to approaching drivers.

Version 0.1

4-6


Sign 416

Sign 417

sign 416. The sign may be repeated once the twoway section of roadway is fully developed if additional emphasis is needed. TWO-WAY TRAFFIC sign 416 should be used when a one way roadway or carriageway becomes a two way roadway. This condition commonly occurs at the end of a dual carriageway. The sign is therefore commonly used with DUAL CARRIAGEWAY ENDS AHEAD sign 424. TWO-WAY TRAFFIC sign 416 should have a white background, a black icon, and a thick red border. Sign 418

4.2.7 LANE ENDS SIGNS 417 AND 418

A SUPPLEMENTARY PLATE sign 589 indicating the distance to the start of the lane reduction taper should be attached below signs 417 and 418.

Signs 417 and 418 warn drivers of vehicles that the right-hand or left-hand lane ends ahead. LANE ENDS signs 417 and 418 should be located on the right side of the roadway on two-way roadways. Whenever possible a sign should be located on the left side as well, particularly when the lane on the left side of a one way carriageway is ending ahead. Signs 417 and 418 should not be used if the reduction in road width does not result in a reduction in the number of lanes. In such instances the appropriate ROAD NARROWS AHEAD sign 421, 422, or 423 should be used. Signs 417 and 418 should be located as indicated in Table 4-1 in advance of the lane reduction taper and clear sight distance to the signs should be available.

LANE ENDS sign 417 and 418 should be provided in advance of any lane drop situation on an arterial road that is not clearly demarcated by overhead guide signs. If necessary the larger diagrammatic warning LANE DROP signs 465 and 466 may be specified for improved conspicuity on arterial roads, and should be used for high speed freeway or expressway locations. LAND ENDS signs 417 and 418 should have a white background, a black icon, and a thick red border.

4-7

Version 0.1


4.2.8 U-TURN AHEAD SIGN 419

ahead be located in advance of the median opening for a U-turn from the opposite direction.

Sign 419 warns drivers of vehicles that they are permitted to make a U-turn at the junction or median opening ahead.

U-TURN AHEAD sign 419 should have a white background, a black icon, and a thick red border.

4.2.9 ROUNDABOUT AHEAD SIGN 420 Sign 420 warns drivers of vehicles of a roundabout ahead.

Sign 419

U-TURN AHEAD sign 419 should be located on the median island of a dual carriageway roadway on the left side of the roadway at a distance from the junction or median opening as indicated in Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 indicating the distance to the point where a U-turn is permitted should be attached below sign 419.

Sign 420

ROUNDABOUT AHEAD sign 420 should be located on the right side of the roadway at a distance from the roundabout as indicated in Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 indicating the distance to the junction to the nearest 20 meters should be attached below sign 420. An additional sign may be placed on the left side of a one-way carriageway.

U-TURN AHEAD sign 419 should be provided in advance of median openings provided specifically for U-turns or at which U-turns are permitted. U-TURN AHEAD sign 419 should not be provided in situations where the availability of a U-turn is apparent or can be accurately anticipated by a driver (e.g., as almost all signalized intersections in Abu Dhabi allow U-turns, no UTURN AHEAD sign 419 is necessary in advance of a signalized intersection).

Sign 420 should only be considered for use when it is not obvious at the distance given in Table 41 that there is a roundabout ahead.

Subject to the distance available, in particular between opposing U-turns through a median island, U-TURN AHEAD sign 419 may be located further from the point of U-turn than the distance given in Table 4-1 in order to reassure drivers that an opportunity to U-turn exists ahead. The distance given on the supplementary plate must reflect such an adjustment in position and indicate the actual distance to the U-turn. Under no circumstances should sign 419 for a U-turn

Version 0.1

ROUNDABOUT AHEAD sign 420 should have a white background, a black icon, and a thick red border.

4.2.10 ROAD NARROWS AHEAD SIGNS 421 TO 423 Signs 421 to 423 warn drivers of vehicles that the roadway ahead narrows from the right side (421), the left side (422) or from both sides (423).

4-8


narrowing situations at roadworks when the extent of the narrowing is less than a full lane width. If the road width reduction results in a reduction in the number of lanes, then LANE ENDS signs 417 and 418 should be used instead. Signs 421 to 423 should be used when the width of a roadway is reduced on the left or right, or both sides, at a quicker rate than would be the case by a standard design taper. ROAD NARROWS AHEAD signs 421 to 423 should have a white background, a black icon, and a thick red border. Sign 421

4.2.11 DUAL CARRIAGEWAY ENDS AHEAD SIGN 424 Sign 424 warns drivers of vehicles that the one way roadway forming part of a dual carriageway road on which they are traveling is about to become a single carriageway roadway carrying two way traffic.

Sign 422

Sign 424

DUAL CARRIAGEWAY ENDS AHEAD sign 424 should be located on the left and right hand sides of a one way roadway which is about to become part of a single carriageway roadway, at a distance from where the two carriageways forming the dual carriageway come together as indicated in Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 indicating the distance to the start of the two way roadway should be attached below sign 424.

Sign 423

ROAD NARROWS AHEAD signs 421 to 423 should be located on the right side of the roadway on two way roadways and, where practical, on both sides of one way roadways. The normal application of these should be for temporary road

4-9

Version 0.1


DUAL CARRIAGEWAY ENDS AHEAD sign 424 may be used with TWO WAY TRAFFIC sign 416. When both signs are used sign 416 should be located as indicated in Table 4-1 and sign 424 should be positioned in advance of sign 416 so that clear sight distance is maintained to sign 416. DUAL CARRIAGEWAY ENDS AHEAD sign 424 should have a white background, a black icon, and a thick red border.

and sign 425 should be located in advance of the structure in such a position that the driver of an over-height vehicle may turn off onto an alternative route. In such instances it may be necessary to provide a custom designed information sign, incorporating sign 425, advising drivers of overheight vehicles of the alternative route. Unless specified otherwise by the Department, the height to be indicated on sign 425 should be 200 millimeters less than the actual minimum clearance measured under the structure, further rounded down to the nearest one decimal point of a meter.

4.2.12 MAXIMUM HEADROOM SIGN 425 Sign 425 warns drivers of vehicles that the clearance available under an overhead structure ahead is restricted to the amount indicated in meters on the sign.

The maximum legal height of a vehicle in the United Arab Emirates is 4.2 meters. MAXIMUM HEADROOM sign 425 should have a white background, a black icon, and a thick red border.

4.2.13 CHILDREN SIGN 426 Sign 426 warns drivers of vehicles of the likelihood that children are on or adjacent to the road ahead due to the presence of a school, playground, or other activity area.

Sign 425

Sign 425 should be located on the right side of the roadway. MAXIMUM HEADROOM sign 425 should not be displayed for any structure with minimum clearance of 5.0 meters or greater. For structures with a clearance less than and 5.0 meters sign 425 should be provided as indicated in Table 4-1 and with a clear sight distance to the sign. In such an instance it is not normally considered necessary to provide prohibition MAXIMUM HEIGHT LIMIT sign 355 at such structures.

Sign 426

CHILDREN sign 426 should be located on the right side of the roadway and, where possible, on the left side as well, at a distance from the start of the area where children are likely to be present as indicated in Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 indicating the specific reason for the

MAXIMUM HEADROOM sign 425 and MAXIMUM HEIGHT LIMIT sign 355 should both be displayed for any structure with a minimum clearance of less than 5.0 meters. Sign 355 should be located as indicated in Section 3.4.10

Version 0.1

4-10


presence of children such as “School” or “Playground” in Arabic and English should be attached below sign 426.

vided at pedestrian crossings located at signalized or sign controlled legs of an intersection. PEDESTRIAN CROSSING AHEAD sign 427 should have a white background, a black icon, and a thick red border.

CHILDREN sign 426 should be provided in advance of any appropriate roadway area which is potentially hazardous to children.

4.2.15 STOP CONTROL AHEAD SIGN 428

CHILDREN sign 426 should have a white background, a black icon, and a thick red border.

Sign 428 warns drivers of vehicles of the presence of a STOP sign 301 ahead and that they should prepare to stop.

4.2.14 PEDESTRIAN CROSSING AHEAD SIGN 427 Sign 427 warns drivers of vehicles that there is a marked and/or signalized pedestrian crossing ahead at which pedestrians have right-of-way.

Sign 428

STOP CONTROL AHEAD sign 428 should be located on the right side of the roadway at a distance from the STOP sign as indicated in Table 41 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 indicating the distance to the STOP sign 301 should be attached below sign 428. An additional sign should be provided on the left side of the roadway on a median island if the roadway is part of a dual carriageway.

Sign 427

PEDESTRIAN CROSSING AHEAD sign 427 should be located on the right side of the roadway and, where possible, on the left side as well, at a distance from the crossing as indicated in Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 indicating the distance to the pedestrian crossing should be attached below sign 427.

STOP CONTROL AHEAD sign 428 should only be considered for use when:

PEDESTRIAN CROSSING AHEAD sign 427 should be provided in advance of all marked pedestrian crossings and mid-block signalized pedestrian crossings. Sign 427 should not be located at a pedestrian crossing to mark the position of the crossing. All unsignalized pedestrian crossings should be marked by GIVE WAY TO PEDESTRIANS sign 303. PEDESTRIAN CROSSING AHEAD sign 427 should not be pro-

• •

It is not obvious at the distance given in Table 4-1 that there is a STOP control ahead, and/or The approach speed is in excess of 60 km/h.

STOP CONTROL AHEAD sign 428 should have a white background, a red icon, and a thick red border.

4-11

Version 0.1


4.2.16 GIVE-WAY CONTROL AHEAD SIGN 429

4.2.17 TRAFFIC SIGNALS AHEAD SIGN 430

Sign 429 warns drivers of vehicles of the presence of a GIVE-WAY sign 302 ahead and that they should prepare to yield right-of-way and stop if necessary.

Sign 430 warns drivers of vehicles that the junction or pedestrian crossing ahead is controlled by traffic signals.

Sign 430 Sign 429

TRAFFIC SIGNALS AHEAD sign 430 should be located on the right side of the roadway at a distance from the traffic signal as indicated in Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 indicating the distance to the traffic signal should be attached below sign 430. An additional sign should be provided on the left side of the roadway on a median island if the roadway is part of a dual carriageway.

GIVE-WAY CONTROL AHEAD sign 429 should be located on the right side of the roadway at a distance from the GIVE WAY sign 302 as indicated in Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 indicating the distance to the GIVE WAY sign 302 should be attached below sign 429. An additional sign should be provided on the left side of the roadway on a median island if the roadway is part of a dual carriageway.

TRAFFIC SIGNALS AHEAD sign 430 should only be considered for use when:

GIVE-WAY CONTROL AHEAD sign 429 should only be considered for use when either or both of the following conditions exist:

•

•

•

•

It is not obvious at the distance given in Table 4-1 that there is a GIVE-WAY control ahead. The approach speed is in excess of 60 km/h.

It is not obvious at the distance given in Table 4-1 that there is a TRAFFIC SIGNAL control ahead, and/or The signalized junction is remote or isolated from other signalized junctions.

In addition to the above situations, sign 430 may be installed for a short period of 3 to 6 months when a new traffic signal is commissioned but must be removed after such a period, subject to the warrant criteria given above.

GIVE-WAY CONTROL AHEAD sign 428 should have a white background, a red icon, and a thick red border.

TRAFFIC SIGNALS AHEAD sign 430 should have a white background and a thick red border.

Version 0.1

4-12


The icon should have a black background with, in descending order, red, yellow, and green lights.

4.2.18 QUAYSIDE SIGN 431 Sign 431 warns drivers of vehicles that there is an unprotected quayside, jetty, or river bank ahead. The sign 431 symbol may be reversed.

Sign 432

Sign 432 should have a white background, a black icon, and a thick red border.

4.2.20 ANIMALS AHEAD SIGN 433 Sign 433 warns drivers of vehicles of the possible presence of attended or unattended animals on or adjacent to the road ahead.

Sign 431

QUAYSIDE sign 431 should be located on the right side of a roadway which runs directly along the side of a quay, jetty, or river bank. Sign 431 should, if practical, be positioned in advance of the unprotected quayside, jetty, or river bank by a distance as indicated in Table 4-1 and with a clear sight distance to the sign.

ANIMALS AHEAD sign 433 should be located on the right side of the road at a distance from the point at which animals are likely to occur near the roadway as indicated in Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 may be attached below sign 433 indicating the distance for which the hazard can be expected to occur.

QUAYSIDE sign 431 should have a white background, a black icon, and a thick red border.

The symbol on an ANIMALS AHEAD sign may be that representing camels, sheep, or goats. If domestic animals are regularly herded across

4.2.19 DRAWBRIDGE AHEAD SIGN 432 Sign 432 warns drivers of vehicles that there is an opening bridge or drawbridge in the road ahead. Currently, Abu Dhabi has no drawbridges. If a drawbridge is eventually constructed in Abu Dhabi, sign 432 should be located as the result of an engineering assessment, meeting the requirements indicated in Table 4-1, and in consideration of clear sight distance. A SUPPLEMENTARY PLATE sign 589 indicating the distance to the drawbridge should be attached below sign 432.

Sign 433

4-13

Version 0.1


roadways, temporary signs displaying the appropriate symbol should be set up in advance of the crossing point. Such signs should preferably indicate the distance to the crossing point. ANIMALS AHEAD sign 433 should have a white background, a black icon, and a thick red border.

4.2.21 LOW-FLYING AIRCRAFT SIGN 434 Sign 434 warns drivers of vehicles that they may be distracted by low flying aircraft or a sudden aircraft noise and to drive with due care.

Sign 435

SPEED HUMP sign 435 should be located on the right side of the roadway at a distance as indicated in Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 should be provided below sign 435. This may indicate one or more of the following: • •

SPEED HUMP sign 435 should have a white background, a black icon, and a thick red border.

Sign 434

4.2.23 TUNNEL SIGN 436

LOW-FLYING AIRCRAFT sign 434 should be located on the right side of the roadway at a distance from the point where the distraction may occur as indicated in Table 4-1 and with a clear sight distance to the sign.

Sign 436 is to warn drivers of vehicles that there is a tunnel on the roadway ahead and that drivers may be subjected to reduced lighting levels or that drivers of certain classes of vehicle may be required by regulatory sign not to enter the tunnel.

LOW-FLYING AIRCRAFT sign 434 should only be provided when aircraft are likely to over-fly the roadway or to fly in close proximity to the roadway.

TUNNEL sign 436 should be located on the right side of the road at a distance from the tunnel entrance as indicated in Table 4-1 and with a clear sight distance to the sign. If a prohibition on certain classes of vehicle entering the tunnel exists, sign 436 should be displayed in combination with the relevant regulatory sign(s). If necessary, sign 436 may therefore be placed at a greater distance from the tunnel than given in Table 4-1. On dual carriageway approaches to a tunnel, sign 436 may be placed on the right and left sides of the roadway.


4.2.22 SPEED HUMP SIGN 435 Sign 435 warns drivers of vehicles that one or more speed humps exist in the roadway ahead and that they should reduce their speed in order to negotiate them.

Version 0.1

The distance for which speed humps are provided, or An appropriate text message such as “Speed Humps” or “Traffic Calming.”

4-14


4.2.25 SLIPPERY SURFACE SIGN 438 Sign 438 warns drivers of vehicles that there is a risk of a slippery surface on the roadway.

Sign 436

TUNNEL sign 436 should have a white background, a black icon, and a thick red border. Sign 438

4.2.24 FALLING ROCKS SIGN 437 SLIPPERY SURFACE sign 438 should be located on the right side of the roadway at a distance in advance of a section of road where the risk of the slippery surface exists, as indicated in Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 may be attached below sign 438 indicating the distance for which the hazard can be expected to occur (e.g., “For 5 km”).

Sign 437 warns drivers of vehicles that there is a risk that rocks may have fallen into the roadway. The sign 437 symbol may be reversed.

SLIPPERY SURFACE sign 438 should have a white background, a black icon, and a thick red border.

4.2.26 GENERAL WARNING SIGN 450

Sign 437

Sign 450, in combination with an appropriate supplementary message, warns drivers of a hazard of a general nature described by the supplementary message.

FALLING ROCKS sign 437 should be located on the right side of the roadway at a distance in advance of a section of road where the risk of falling rocks exists, as indicated in Table 4-1 and with a clear sight distance to the sign. A SUPPLEMENTARY PLATE sign 589 may be attached below sign 437 indicating the distance for which the hazard can be expected to occur (e.g., “For 5 km”).

GENERAL WARNING sign 450 should be located on the right side of the roadway at a distance as indicated in Table 4-1 and with a clear sight distance to the sign. Sign 450 should only be displayed in conjunction with a SUPPLEMENTARY PLATE sign 589. Permitted messages for use below sign 450 are as follows: • •

FALLING ROCKS sign 437 should have a white background, a black icon, and a thick red border. 4-15

Drifting sand. Uneven road.

Version 0.1


ing the position of physical hazards such as culverts, bridge structures, large sign supports, traffic island gores, guardrails, etc., to drivers. In some instances, such as a sharp curve, hazard markers may be used to delineate the curve and so draw attention to the severity of the curve.

4.3.1 HAZARD PLATE SIGNS 451 AND 452 Signs 451 and 452 warn motorists of the actual position of physical objects which are placed so close to the roadway as to represent a hazard or potential hazard if vehicles should collide with them.

Sign 450

•

Overhead cables (with a height clearance).

If the conditions indicated above change or are removed, the sign should be removed. GENERAL WARNING sign 450 is appropriate to many conditions which occur at roadworks sites or in association with roadworks sites (see also Chapter 7). The sign may also be appropriate for other temporary conditions. In such circumstances the exclusive black symbol on a yellow background color code used for roadworks signs should be used. Typical messages used in temporary or roadworks situations are: • • • • • • • • • • •

Sign 451

Sand Surveying. Reduced visibility. Loose stones. Uneven road. Slippery surface. Road ends. Flood. Construction traffic. Soft shoulder. Surface step (dip).

HAZARD PLATE signs 451 and 452 should be located as close as possible to the physical hazard to identify its position. A number of evenly spaced HAZARD PLATE signs 451 or 452 may also be used to demarcate open ditches, high embankments, and ill-defined curves. See Table 4-3 for guidance on spacing. HAZARD PLATE signs 451 and 452 should always be installed so that the “arrow” points towards the roadway and away from the hazard. Signs 451 and 452 should be mounted so that the


4.3

Table 4-3 Spacing on Curves for Signs 451, 452, 454, and 455 Curve Radius Sign Spacing “S” (meters) (meters) 60 8-15 150 15-25 300 25 600 25

HAZARD MARKER SIGNS

The signs in this group have the specific function to mark an actual hazard adjacent to the roadway. The majority of uses therefore relate to identify-

Version 0.1

Sign 452

4-16


lower edge is 600 millimeters above ground level for the 600 millimeter by 150 millimeter size and 1200 millimeters above ground level for the 1200 millimeter by 300 millimeter size. Figure 4-1 illustrates a number of typical HAZARD PLATE sign applications. The larger of the two sign sizes should be used when the posted speed limit is 80 kilometers per hour or greater. Sign 454

HAZARD PLATE signs 451 and 452 should have a red background with white diagonal stripes.

Sign 455

ment of the roadway when these conditions represent hazards or potential hazards. SINGLE CHEVRON signs 454 and 455, when used independently, should be placed as close as possible to the hazard that it is intended to mark. SINGLE CHEVRON signs 454 and 455 may be mounted to point to the right and to the left. The arrows should always point towards the roadway

4.3.2 SINGLE CHEVRON RIGHT (OR LEFT) SIGN 454 (OR 455) Signs 454 and 455 warn motorists of the actual position of physical objects or of the actual align-

600

150

600

Culvert

Bridge deck

Abutment

1200

1200

300

Figure 4-1 Typical Hazard Plate Applications

4-17

Version 0.1


passing in front of the sign. The application of signs 454 and 455 is very similar to that of signs 451 and 452. In general, signs 451 and 452 should be used in a lower speed or less hazardous environment than signs 454 and 455.

for use in place of sign 326 to mark island gores if these are on a particularly difficult vertical or horizontal alignment. In such an application signs 454 and 455 should be mounted side-byside in the gore but a separator is not necessary.

SINGLE CHEVRON signs 454 and 455 may also be used in sets whereby the signs are spaced at regular intervals to define a sharp curve (e.g., on a 180° or 270° loop ramp) or to define the edge of a high embankment or a guard rail at the top of such an embankment. Figure 4-2 illustrates a typical example of such an installation and Table 4-3 gives guidance on the spacing of the signs. Signs 454 and 455 should be considered

When SINGLE CHEVRON signs 454 and 455 are placed at intervals round a sharp curve they should be positioned so that one sign lies as close as possible to the line of extension of the tangent approaching the curve, and so that the sign lies straight-ahead for a driver in the near side lane. Other signs should then be positioned forwards and backwards round the curve so that the curve is fully delineated, approximately from tangent First sign to be placed

455 TP

455 S

455

See Table 4-3 for spacing “S”

455

TP

455

454

Figure 4-2 Examples of Applications of Sign 454 and Sign 455

Version 0.1

4-18


point to tangent point. It is necessary that, in order to properly define the curve through both vertical and horizontal changes, at least three signs are visible at any time while driving through the curve.

MULTIPLE CHEVRON RIGHT (or LEFT) signs 456 and 457 may be used at a sharp bend when the severity of the bend is not likely to be adequately conveyed by advance warning sign 412 or 413. The signs should comprise a minimum of three chevron modules. If a sharp bend is sufficiently long the number of modules may be increased to a maximum of four. If it is necessary to sign a longer sharp bend this should be done using signs 454 or 455 as illustrated in Figure 42. Figure 4-3 illustrates the use of signs 456 and 457.

SINGLE CHEVRON signs 454 and 455 should have a white background, a red chevron, and a thin red border.

4.3.3 MULTIPLE CHEVRON RIGHT (OR LEFT) SIGN 456 (OR 457)

MULTIPLE CHEVRON RIGHT sign 456 may also be used to identify the sharp change of direction required on entering a roundabout. Sign positions are illustrated in Figure 4-3. This application should only be considered when the view of the center of the roundabout is restricted due to the geometry of the approach and entry, or due to the aesthetic treatment of the roundabout. If the latter is such that the shape of the roundabout is no longer evident advance warning sign 420 may be specified.

Signs 456 and 457 warn motorists of the actual position of a very sharp bend or change in direction in the roadway.

Sign 456

Sign 456 (or 457) should have a white background, red chevrons, and a thin red border.

4.3.4 T-JUNCTION CHEVRON SIGN 458

Sign 457

Sign 458 warns drivers of vehicles that the road they are traveling on terminates at a T-junction

456

457

456

Figure 4-3 Typical Application of Multiple Chevron Signs 456 and 457

4-19

Version 0.1


assist drivers to use complex roadways more safely and efficiently. Sign 458

The complex geometric conditions referred to above often involve merging and/or weaving maneuvers without stop or give way control. These are driving actions that many drivers find difficult to undertake and diagrammatic signs actually offer a combination of warning and guidance in such situations.

and in so doing the sign identifies the position of the far side of such a junction. T-JUNCTION CHEVRON sign 458 should be located on the far side of the T-junction, at 90° to the direction of approach from the side road, so that the sign is located at the rear of a sidewalk in an urban area, or at the rear of a shoulder or approximately two meters from the edge of the roadway, in a rural area. Use of sign 458 should be considered for high speed (60 km/h or more) approaches to T-junctions, particularly when there is no street lighting, and where a guide sign would not otherwise be used.

The types of message that may be displayed on a diagrammatic sign can be categorized. The sign group has therefore been subdivided according to these categories as follows: • • •

T-JUNCTION CHEVRON sign 458 should comprise a minimum of six chevron modules, three pointing to the right and three to the left.

Several of these categories have the potential to provide many signs. Some of these signs vary significantly in their sign face message, and therefore design, while others represent limited variations on the themes established by the earlier alternatives. In the following sections only a limited number of signs are illustrated. Where it is appropriate, design rules are stated for signface design.

Sign 458 should have a white background, red chevrons, and a thin red border.

4.4

DIAGRAMMATIC SIGNS

The signs in this group are essentially for use in situations where the size and shape of triangular advance warning signs limits the pictorial warning message that can be displayed, and/or the overall conspicuity of the sign. The situations that tend to be indicated on diagrammatic signs are commonly ones that occur on higher speed roads. The diagrammatic nature of the message given by these signs means that they often depict the geometric arrangements of the lanes and/or the whole roadway.

The following characteristics are appropriate to all diagrammatic signs: •

Geometric design of roadways should result in drivers having sufficient time and space to negotiate even complex arrangements safely and without undue doubt or confusion. In reality, due to the need to satisfy many geometric requirements within a limited space and under traffic flow conditions that may be nearing capacity, complex road conditions do occur. While the availability of diagrammatic signs should not be seen as an excuse for creating complex geometric designs of roadways, the signs may offer some options to Version 0.1

Traffic movement is affected by an obstruction. Additional lane and lanes merge signs. Lane use control by regulation.

•

4-20

The basic rectangular shape of the minimally sized sign should have a ratio of height to width of 4 to 3. Recommended standard basic sign sizes should be 1200 millimeters (H) x 900 millimeters (W), 1600 millimeters (H) x 1200 millimeters (W) and 2400 millimeters (H) x 1800 millimeters (W) for ground mounted signs. If used overhead, recommended basic sign sizes should be 2400 millimeters (H) x 1800 millimeters (W) and 3200 millimeters (H) x 2400 millimeters (W). These dimensions are exclusive of supplementary information plates, if applicable. The width of the basic sign may be increased when three or more arrows are to be displayed, in increments equal to one quarter of the basic width.


• •

•

•

The sign face message should depict only one situation requiring an action on the part of the drivers to whom the sign applies. An “obstruction” commonly means a physical obstacle such as a concrete barrier or a Wsection guardrail but also includes perceived “obstructions” to vehicle movement. For example, the obstruction may be an introduced median island or a lane-drop situation with a sufficient run-off and recovery area provided. In this case, the “obstruction” is illustrated on the sign by a solid red block. Arrows pointing in the direction of travel should point upwards on the sign and be the full height of the sign, with specified clearances, whereas arrows depicting opposing traffic flows should point downwards on the sign and be of a reduced length (shorter by approximately the length of two arrow heads). If a SUPPLEMENTARY PLATE sign 589 is required with a diagrammatic sign it should be a separate plate mounted below the sign for ground-mounted signs.

depicting a traffic movement affected by an obstruction include: • • •

•

A lane drop on a multilane, high-speed roadway. The temporary deviation of traffic through a median island, around a structure, or similar obstacle. The passage of traffic alongside a physical barrier that either reduces normal lane width or normal lateral clearances. Such a physical barrier may be an upstanding concrete barrier, a row of cones or delineators separating traffic streams, or similarly, cones or delineators protecting a limited excavation area. The passage of two-way traffic around an obstruction such as the beginning of a median island.

4.4.1.1

LANE DROP SIGNS 465 (FROM THE RIGHT) AND 466 (FROM THE LEFT)

Signs 465 and 466 warn motorists that a lane drop lies ahead for a right-side lane drop or a leftside lane drop, respectively.

Diagrammatic signs are particularly appropriate to the temporary detours common during major roadworks (see Chapters 7 and 8). Their use is, however, also appropriate in certain situations that can be considered as permanent even though they may be scheduled for medium- to long-term improvement. Since many diagrammatic signs only have a temporary application they are not illustrated in this chapter. As a result, the signs that are illustrated do not have sequential numbers; the remaining signs are illustrated in Chapter 7.

LANE DROP signs 465 and 466 should be considered for use in traffic situations that are either known to have substandard geometry that cannot be rectified in the short-term or that have, for whatever reason, not been sufficiently improved by the provision of normal advance warning signs. LANE DROP signs 465 and 466 may be provided in advance of the point at which the lane is dropped. An appropriate SUPPLEMENTARY PLATE sign 589 indicating the distance to the lane drop mounted below the sign should be provided. At the start of the lane drop taper signs 465 and 466 should be provided without such a supplementary plate.

The normal warrants for overhead signs can be used to decide whether a diagrammatic sign should be used in an overhead position. Diagrammatic signs may be displayed in association with overhead direction signs.

4.4.1 TRAFFIC MOVEMENT AFFECTED BY OBSTRUCTION SIGNS

LANE DROP signs 465 and 466 should have a white background and a thin red border. The icon should be black and red, with the arrows representing traffic movement in black and the obstructions in red.

As has been noted above, an “obstruction” in the context in which signs in this group are to be used may be real or perceived. Situations that may warrant the use of a diagrammatic sign

4-21

Version 0.1


4.4.1.2

Sign 465

Sign 472

Sign 466

Sign 473

4.4.2 ADDITIONAL LANE AND LANES MERGE SIGNS

BEGINNING/END OF MEDIAN SIGNS 472 AND 473

Signs 472 and 473 warn motorists that the roadway ahead has a median starting or ending and that this may, in the case of sign 472, represent a significant hazard in the roadway going in the one direction, or that, in the case of sign 473, traffic streams become two way beyond the end of the median island, which in turn may be a potentially hazardous condition.

This group of signs is used to indicate to drivers that the roadway beyond the sign increases in width by one lane, that an additional stream of traffic is entering the roadway, or that traffic may be merging, which may result in some weaving action. As no decrease in speed is implicitly required for the roadway conditions these signs warn of, there are no specified minimum or maximum advance positioning guidelines. The Engineer should use professional judgement in positioning these signs, taking into account all relevant conditions and variables.

BEGINNING/END OF MEDIAN signs 472 and 473 should have a white background and a thin red border. The icon should be black and red, with the arrows representing traffic movement in black and the obstructions in red.

Version 0.1

4-22


4.4.2.1

ADDITIONAL LANE SIGNS 480 AND 481

4.4.2.2

JOINING LANE SIGNS 482 OR 483

Signs 482 and 483 warn drivers of vehicles that an extra lane carrying joining traffic comes into the roadway from the right (or left) and that merging and weaving maneuvers can be expected.

Signs 480 and 481 warn motorists on a section of road that an additional continuous lane will be added ahead, at the distance indicated below the sign. The principal value of these signs is to reassure drivers, when in heavy traffic, that overtaking opportunities will occur ahead due to the additional lane. Such a sign need only be placed 500 meters to one kilometer in advance of the start of the additional lane. The sign type is appropriate for freeways and rural roads.

Sign 482 should preferably be positioned so that drivers on the main carriageway and drivers on the entering lane can both see the sign. If this is not possible both signs 482 and 483 may be used to warn drivers. Because road configurations requiring use of this sign vary widely, there is no recommended minimum or maximum placement distance. Good engineering judgement should be exercised in locating the signs.

ADDITIONAL LANE signs 480 and 481 should have a white background, a black icon, and a thin red border.

JOINING LANES signs 482 and 483 should have a white background, a black icon, and a thin red border.

Sign 480

Sign 482

Sign 481

Sign 483

4-23

Version 0.1


4.4.2.3

LANES MERGE SIGNS 490 AND 492

streams. Advance signs may also be used, particularly on freeways, and these should include a SUPPLEMENTARY PLATE sign 589.

Sign 490 warns of the merging of two lanes. The use of this sign may be appropriate at at-grade junctions to emphasize the need for drivers to undertake merging actions or maneuvers. As such the sign only shows the two lanes involved in the merging action.

Signs 490 and 492 should have a white background, a black icon, and a thin red border.

4.4.3 LANE USE CONTROL BY REGULATION

Sign 492 warns of the merging of two lanes on a high-speed free-flow roadway. Such roadways are commonly freeways or freeway ramps where there is little or no tolerance for traffic slowdown or back-up from the point of merge. It is therefore recommended that the signs indicate all lanes at the point of merge. The signs should be erected close to the gore of the merge area on freeways, or on both sides of the roadway at atgrade junctions. Where possible they should be visible to drivers in both approaching traffic

The signs in this group indicate that one or more individual lanes in the roadway ahead are subject to some form of special regulatory control. The purpose of such control is to improve the operational efficiency of the roadway concerned. The most common application of this control is a prohibition of heavy vehicle or truck traffic on one or more lanes. Another possible application is at unusually configured intersections where turning restrictions are imposed on one or more of the basic lanes. Because of the regulatory message it is a requirement that such signs indicate all lanes on the roadway. These diagrammatic signs, in effect, provide a background for some type of regulatory sign. The examples given in Section 4.4.3 should be considered as typical. Once a regulatory sign has been superimposed on the diagrammatic background the overall sign takes on a regulatory function. 4.4.3.1

LANE USE CONTROL — TRUCKS AND BUSSES SIGNS 484 AND 485

In Abu Dhabi Emirate, trucks are allowed to use only the right-most lane on any road, except when preparing to make a left turn. Sign 484 and sign 485 impose this prohibition on the use of lanes by trucks and as such the signs warn motorists of the special regulatory circumstances existing on those lanes. The lane prohibition also applies to busses, with two exceptions:

Sign 490

1. On roads having four or more lanes, busses are allowed to use the second lane. 2. On roads having two or three lanes, busses are allowed to leave the right-most lane to overtake other vehicles, but must then return to the right lane. Sign 492

Version 0.1

4-24


Sign 484

Sign 486

leave that lane prior to the intersection, otherwise they will be required to make a left turn. The LANE USE CONTROL — DIRECTIONAL RESTRICTION series of signs supplement pavement markings and provide advance notice of a lane use control condition ahead. These signs are not intended for routine use at all standard signalized intersections where geometry clearly indicates intended turning lanes. Rather, its use should be restricted to unusual intersection configurations where one of the basic roadway lanes unexpectedly becomes an exclusive turn lane. A likely usage of this sign will be at a T-junction on the through leg containing the left turn, when the geometry is such that one of the basic roadway lanes becomes an exclusive left turn lane. Its use on other legs of the T-junction will not ordinarily be required.

Sign 485

The signs should be spaced at approximately five-kilometer intervals. LANE USE CONTROL — TRUCKS AND BUSSES signs 484 and 485 should have a white background and a thin red border. The icon should be black with the prohibitory symbol (circle and diagonal slash) in red. 4.4.3.2

LANE USE CONTROL — DIRECTIONAL RESTRICTION sign 486 should have a white background and a thin red border. The icon should be black with the regulatory symbol in blue.

LANE USE CONTROL — DIRECTIONAL RESTRICTION SIGN 486

4.5

Sign 486 imposes a mandatory restriction of movement LANE USE CONTROL — DIRECTIONAL RESTRICTION on one of the basic through lanes of a roadway. In the example shown it warns motorists that the leftmost of the basic through lanes becomes, by regulation, an exclusive left turn lane at the intersection. Drivers wishing to continue straight ahead must

HIGH VEHICLE WARNING SIGN 495

Sign 495 is typically located in advance of gantry or cantilever signs and points high vehicles to a short, low-grade detour that does not pass underneath the horizontal arm of the sign but instead around the sign’s support column.

4-25

Version 0.1


Sign 495

HIGH VEHICLE WARNING sign 495 should be located on the right side of the roadway at a distance in advance of the gantry or cantilever structure as indicated in Table 4-1. If deemed appropriate by the engineer, sign 495 may have flashing yellow caution lights placed at its top. Sign 490 should have a red background, a white border, and the text should be white.

Version 0.1

4-26


5

GUIDE SIGNS

5.1

PRINCIPLES OF DIRECTIONAL GUIDANCE

• •

•

The objective of the Abu Dhabi Guide Sign system is to provide guidance to visitors to and residents of Abu Dhabi. To accomplish this objective, guide signing must do the following: • • • •

•

Enable drivers to find their way to far more destinations than could possibly be signed. Avoid confusing drivers with too much information. Present drivers with predictable information. Present drivers with advance notice so that directional changes can be safely made.

• •

5.1.2 CLASSIFICATION OF GUIDE SIGNS Guide signing can be divided into signs that are most applicable for at-grade junctions (intersections and roundabouts) and those that are applicable for grade-separated, free-flow interchanges.

It is the aim of the following described guidesign system to accomplish these objectives.

5.1.1 METHOD OF PROVIDING GUIDANCE

At-grade junctions, whether intersections or roundabouts, generally have three choices of direction: ongoing, left, and right. These movements, especially the turns, are made at slow speed and usually under traffic signal control. Since at-grade junctions are, or should be, relatively uniform and deliberate in operation, guide signing will consist of simple ADVANCE STACK signs, advising motorists of available directions of travel at the junction ahead, allowing sufficient advance notice for driver orientation and appropriate action. CHEVRON DIRECTION signs, located in the vicinity of the turning area, identify the point of turning action and provide motorists with confirmation of their intended movement. In addition, a STREET NAME sign is provided at each junction as a secondary source of driver orientation and guidance.

The guide-signing system must be able to provide a driver with two basic pieces of information: • •

Use of route numbers as the primary method of guidance on numbered routes. Use of street names as the primary method of identification and guidance on non-numbered routes and as a secondary means of guidance on numbered routes. Strict criteria for destinations displayed for each route as an orientation guide for road users. Strict criteria for additional destinations to be displayed on supplemental guide signs, separate from the primary guide signs. Color coding of signing. Consistency in the application of signing.

The current location of the driver within the roadway system, and When facing a choice of several possible directions of travel, which one should be taken to reach the desired destination.

Driving is a complex process requiring a driver to observe, comprehend, analyze and act upon a wide variety of visual input. It is critical that guide signs present information to the driver in a predictable, clear and simple manner. This information must be presented far enough in advance of the point of potential action to permit the driver to determine what action is required and then allow him to safely and orderly execute any directional changes that may be necessary.

Grade-separated junctions present a much different set of circumstances to motorists. Grade-separated junctions are generally located on highvolume and/or high-speed roadways and are designed to handle traffic in a free-flow operational mode. It is thus important that motorists be advised clearly and well in advance of their intended point of departure. This will allow

The guide sign system for Abu Dhabi is based upon a framework of fundamental principles, summarized as follows:

5-1

Version 0.1


ample opportunity to make one or more lane changes to be properly positioned to execute a full-speed exit from the roadway. Inadequate and/or unclear directions may contribute to driver indecision; speed reduction or stopping; and abrupt, last-minute maneuvers, all of which will be extremely dangerous under high-speed, highvolume conditions.

Emirate that provide through travel between major cities and/or other emirates. Emirate Routes are designated at present with a two-digit number (exception: bypass routes have a threedigit designator, the first digit being the sequential number assigned to the bypass and the last two digits being the primary route being bypassed, e.g., the first bypass to Emirate Route 22 would be numbered 122). Routes 88 and 99 are reserved for possible future Emirate Routes. Odd-numbered Emirate Routes run generally in an east-west direction, and even number routes in a north-south direction.

Thus, a different type of signing is required for grade-separated interchanges. This consists of one or more ADVANCE EXIT DIRECTION signs, up to 2000 meters in advance of the exit point. These signs advise motorists of destinations reached from the next exit, appropriate lane position to access that exit, and distance to exit point. These ADVANCE EXIT DIRECTION signs are generally repeated at intervals as the exit approaches. When the exit point is reached (also known as the theoretical gore or painted nose) the motorist is advised by an EXIT DIRECTION sign that this is the point of departure. The physical nose is also marked by a GORE EXIT sign to further reinforce the action of exiting the mainline.

The second level of primary routes are the primary arterials (with some secondary arterials) within the Abu Dhabi urban area. These routes provide access from one community in the Abu Dhabi urban area to another. Abu Dhabi or “AD” Routes are designated with a two-digit number, from 10 to 99. Even number routes run generally parallel to the coast line, and odd numbered routes run generally perpendicular to the coast line. Routes in the nineties are located along the coast line and along the Dubai Emirate border, descending in order moving inland and towards Abu Dhabi Emirate respectively.

Separate and apart from the above described primary guide signing will be a system of supplemental destination signing. Supplemental destinations are local facilities or attractions that are primarily of interest to visitors to Abu Dhabi. To avoid overloading and overcomplicating the primary guide sign system, these supplemental destinations are signed separately. Supplemental signing may be used for both at grade and gradeseparated junctions.

Although not absolutely necessary that it be adhered to in the future, an initial attempt was made to keep routes in as sequential an order as possible. Some route numbers in the sequence have been skipped to allow the future allocation of these numbers to new routes in a near sequential order.

5.1.3 ROUTE NUMBERING SYSTEM

5.1.4 PRIMARY DESTINATIONS

At the heart of Abu Dhabi guide signing is the route numbering system. Route numbers allow the motorist to develop a simple series of directions to follow while traveling from one part of the greater Abu Dhabi urban area to another. Route numbers will be prominently and predictably displayed on the guide signs, making driver orientation and direction clear and unconfusing.

The Road Department categorizes destinations eligible for use on primary guide signs into three types:

Two routing classifications have been established, as shown in Figure 5-1. Emirate or “E” Routes are the major roadways in Abu Dhabi

In transliterating Arabic destination names to English, the article al should be transliterated without regard to the Arabic sun and moon let-

Version 0.1

1. Control destinations for Emirate Routes. 2. Control destinations for non-Emirate Routes. 3. Other local destinations for non-Emirate Routes.

5-2


THIS PAGE RESERVED FOR FIGURE 5-1, ROUTE NUMBERING SYSTEM

5-3

Version 0.1


ters. Unless it has been common practice to spell a destination’s name otherwise and signs already exist using that spelling, the English spelling should follow the Arabic spelling, not the Arabic pronunciation (e.g., Sas Al Nakhl, Al Shahama). 5.1.4.1

Port Zayed, and the control destination for the western terminus of Al Corniche Road is Al Ras Al Akhdhar/Breakwater. Likewise, the control destinations for Matar Road are Dubai/Al Ain and the Corniche. The Department does not specify an “approved list” of control destinations for non-Emirate Routes. Consultants are expected to exercise good engineering judgement in selecting control destinations for use on these guide signs and these destinations are subject to the approval of the Department.

CONTROL DESTINATIONS FOR EMIRATE ROUTES

Control destinations are associated with each Emirate Route. The purpose of control destinations is to provide orientation with respect to direction of travel along that numbered route.

5.1.4.3 The control destinations for the Emirate Routes are the cities shown in Table 5-1. These control cities are intended to function for long-distance travelers, advising them of the major city reached by following that route in that direction of travel. In the case of selected routes, an intermediate destination of Abu Dhabi is given for travel in one direction. The control city of Abu Dhabi should be used until the Abu Dhabi urban area is reached, at which time the control city for all onward signing should be the end destination ahead. 5.1.4.2

In addition to the control destinations described in Section 5.1.4.2, other local destinations are also eligible for use on non-Emirate Route guide signs. To qualify for use on guide signs, these destinations should be either locations frequented by the public or major landmarks that will assist in orientation. Eligible destinations include towns or neighborhoods (e.g., Musaffah, Al Khalidiya), public medical facilities (e.g., Al Jazeera Hospital), government offices frequented by the public (e.g., Immigration, Traffic Police), major mosques and religious sites (e.g., Eid prayer grounds), selected military installations (e.g., Officers Club, GHQ), major streets (e.g., Musaffah Road, Al Corniche Road) and well-known or publicly popular locations (e.g., major malls, colleges and universities, petroleum refineries).

CONTROL DESTINATIONS FOR NON-EMIRATE ROUTES

For major Abu Dhabi roadways that are not Emirate Routes, control destinations are to be a logical, well-known terminus of the route or roadway. For example, the control destination for the eastern terminus of the Al Corniche Road is

Route Number

Table 5-1 Emirate Routes Control Destinations End Destination Intermediate (South or West) Destination

E10

Abu Dhabi

E11

Al Sila, Saudi Arabia, Qatar

E22

Abu Dhabi

Version 0.1

OTHER LOCAL DESTINATIONS FOR NON-EMIRATE ROUTES

End Destination (North or East) Al Shahama

Sas Al Nakhl, Khalifa City, Abu Dhabi International Airport Jebel Dhanna, Al Ruwais, Al Dubai Marfa, Tarif, Liwa Oasis, Abu Al Abyadh, Musaffah, Al Mafraq, Bani Yas, Khalifa Bin Zayed City, Mohammed Bin Zayed City, Abu Dhabi, Abu Dhabi International Airport, Ghantoot, Al Shahama, Al Samhah, Seih Shoaib, Jebel Ali Musaffah, Al Mafraq, Bani Yas, Al Al Ain, Oman Wathba, Fiya, Al Khatim, Al Khazna

5-4


The Department does not specify an “approved list” of this type of destination. Consultants are expected to exercise good engineering judgement in selecting local destinations for use on guide signs and these destinations are subject to the approval of the Department.

However, some site-specific locations may require more than one similar destination. In this case, the name will be retained until trailblazing can be used without creating confusion as to which destination is which. Such cases must be submitted to Department for approval prior to implementation.

5.1.5 SUPPLEMENTAL DESTINATIONS

5.1.6 COLOR CODING The use of a specific sign background color code serves as an aid to motorists in searching out and recognizing the type of guide sign they are looking for. Color coding will also aid in distinguishing the type of route the motorist is currently on or looking to go onto.

Certain facilities or attractions have been determined as being qualified to receive separate signing, supplemental to the primary guide signs. The purpose of the supplemental signing is to provide assistance to motorists, unfamiliar with Abu Dhabi, in finding their way from a numbered route to the facility being sought. This signing is provided primarily for the benefit of tourists, but may be found to be useful at times for Abu Dhabi residents.

Three colors are used for the background color of guide signs; blue, green, and brown. The use of the colors are described in Table 5-3 (see Chapter 7 for instructions on roadworks guide signs).

Table 5-2 lists the destinations that are approved by the Abu Dhabi Municipality for supplemental signing destinations are those which warrant supplemental signing beginning at the point of departure from the nearest Emirate Route and signing all necessary turns on the most direct routing from that departure point to the appropriate access point of the destination being signed. The nearest numbered route to numbered route turns to reach the supplemental locations will also be signed.

A special case in the color coding occurs within a signalized intersection or a roundabout when an Emirate Route and an Abu Dhabi Route intersect one another. Advance guide signs on the Emirate Route will have a blue background color and advance guide signs on the Abu Dhabi Route will have a green background color. However, CHEVRON DIRECTION signs 515 will be located in or near the junction, to guide motorists in making turns onto their intended route. Since some junctions include both an Emirate Route and an Abu Dhabi Route, the color coding for CHEVRON DIRECTION sign 515 should be that each of these signs will be the color of the type of route that it provides direction to. That is, signs giving direction onto an Emirate Route should have a blue background, and those giving direction to an Abu Dhabi Route should have a green background.

Supplemental signs placed on a numbered route should have both the symbol and the identifying name of the destination being signed. Subsequent supplemental signing from the numbered route to the destination should be provided by supplemental trailblazer signs displaying only the pictorial symbol without the identifying place name. Table 5-2 Locations Eligible for Supplemental Destination Signing Major hotels and convention centers Major clubs Public beaches Cultural Foundation Heritage/Bedouin Village Zayed Sports City Gulf International Exhibition Center Traditional markets (souqs) Note: Locations are in no order of relevance.

A similar type of color coding anomaly occurs at entrance and exit ramps leading from an Emirate Route to an Abu Dhabi Route and visa-versa. The color coding rule in this case should be that a ramp should assume the route classification of the route to which the ramp is leading. Thus, signs positioned well downstream on a ramp, that are intended to be read only by motorists on the ramp should have the background color of the

5-5

Version 0.1


Blue

Green

Brown

White

Table 5-3 Guide Sign Background Color Coding All primary guide signs of all types that are located on Emirates Routes shall have a blue background color with white legend. Emirate Route emblems, shall always have a blue background color regardless of the background color of the sign on which they are located. All primary guide signs of all types that are located on Abu Dhabi Routes shall have a green background color with white legend. Abu Dhabi Route emblems shall always have a green background color regardless of the background color of the sign on which they are located. Supplemental signs, which provide guidance to approved supplemental destinations, shall have a brown background with a white legend. Supplemental signs shall always have a brown background regardless of whether they are located on an Emirate Route, Abu Dhabi Route or a local street. They will also commonly display a symbolic representation of the destination as a black symbol on a white square background. Once a supplemental destination is reached, further subordinate signs pertaining to that destination shall also have a brown background. For use with Text Sign 588. High Vehicle Exit Sign 586, and Supplementary Plate 589.

route the ramp leads to. If in an unusual situation a ramp leads to a split with one direction of the split being an Emirate Route and the other direction of the split being an Abu Dhabi Route, the guide sign background color for that ramp should be blue.

use to get from their current location to their intended destination. Therefore, route numbers must be displayed clearly and prominently on every primary guide sign. Large, distinctively shaped and colored route emblems with large yellow colored English numerals provide a highly conspicuous and legible route identification.

5.1.7 INFORMATION TO BE DISPLAYED ON SIGNS

The creation of a new route and associated control destinations should be referred to the Abu Dhabi Municipality Road Department for review and approval. In this case a formal amendment to this manual should be issued so that all other signing associated with that route will be consistent. By strict adherence to route numbers and control destinations, motorists will see a consistent display of destinations when turning onto and following the guide signs on that route. They will not be left to guess at what destinations might appear on subsequent signs. This is an important principle of guide signing. That is, once a destination appears on a guide sign, it must be repeated on each subsequent guide sign until the destination is reached. Thus, the need for strict control of the number of destinations and the consistent use of these destinations on all signs.

It is important that each type of guide sign consistently display all necessary eligible information, but not display any additional or extraneous information. Strict criteria have been established, as indicated in Table 5-4, concerning what information may or may not be shown on each type of guide sign. The Abu Dhabi guide sign system is intended to provide motorists with directions for traveling along a particular numbered route (be it an Emirate Route or an Abu Dhabi Route) and advising turns from that route onto another numbered route (an Emirate Route or an Abu Dhabi Route). Generally, guide signs will not be used on unnumbered routes nor for advising turns from a numbered route onto an unnumbered street. Street name signs installed under the Abu Dhabi street and plot numbering system will identify those streets with a street name sign (whether that street name is a word name or a number name).

On rare occasions, it may be desirable to provide a guide sign to direct motorists from a numbered route to an unnumbered route. In this situation, street names or numbers can substitute for route numbers. Such cases should be reviewed with the Abu Dhabi Municipality Road Department in consideration of the following:

The primary piece of information to be included on guide signs is the route number. Motorists unfamiliar with Abu Dhabi will consult a route or street map to determine what numbered routes to

Version 0.1

5-6


• • •

Lane Drop Panel

Supplemental Symbols

Supplemental Destinations

Street Name

Is it necessary to provide a guide sign other than a street-name sign to identify the intersecting roadway? If so, does the importance of the intersecting roadway warrant providing it with a route number and control destination(s)? If not, then the guide sign series should display the name of the street or other approved name as the destination and omit the route number and emblem.

Airport Symbol

1 1 1 0 1 1 1 0 0 0

City Center Symbol

0 0 0 4 2 0 0 0 0 4

Control Destination

0 0 0 4 2 0 0 0 0 4

Route Number Emblem

0 0 0 0 0 2 2 1 0 0

Downward Lane Arrow

4 0 3 4 2 2 0 4 0 3 4 2 0 0 4 0 3 4 2 2 0 4 0 0 0 0 0 0 4 0 4 4 2 2 0 0 4 4 4 2 2 4 4 0 4 4 2 2 0 0 4 4 4 2 2 0 4 0 0 0 0 0 0 4 0 0 0 0 0 0 0 = Not Eligible Ever 1 = Not Eligible Ordinarily Key:xx 2 = Eligible Where Applicable 3 = Use on Emirate Routes Only 4 = Mandatory in All Cases

Directional Arrow

Sign Type ADVANCE HORIZONTAL STACK sign 511 ADVANCE VERTICAL STACK sign 512 ADVANCE MAP sign 513 ADVANCE SUPPLEMENTAL sign 514 CHEVRON DIRECTION sign 515 ADVANCE EXIT DIRECTION sign 551 EXIT DIRECTION sign 552 ONGOING DIRECTION sign 553 GORE EXIT signs 554, 555, 556 SUPPLEMENTAL EXIT sign 557

Distance to Exit

Table 5-4 Information Eligible for Display on Guide Signs

stituencies to add other destinations to the guide signs. Such destinations may be significant and of interest in their own right, but the temptation to give in to such pressure must be resisted. Experience elsewhere has demonstrated that once additional destinations begin to appear on guide signs, it sets a precedent that makes refusal of further destinations nearly impossible. Table 5-5, though not all inclusive, provides an indication of the types of places not warranting display on guide signs within the roadway right of way.

Such instances should be extremely rare and limited mainly to cases on rural, high speed, high order facilities (freeways) where advance signing is necessary.

Guide signs for the types of places listed in Table 5-5 can only be implemented with the prior approval of Abu Dhabi Municipality Road Department.

5.1.8 DESTINATIONS NOT ELIGIBLE FOR DISPLAY ON GUIDE SIGNS

5.1.9 TRAILBLAZING SIGNING The use of distinctive and recognizable symbols placed along a route to guide and reassure motorists that they are taking the correct roadways to reach a specific destination is called trailblazing.

Sections 5.1.4 and 5.1.5 list control destinations and supplemental destinations eligible for display on primary and supplemental signs. There always exists the desire and pressure from outside con-

5-7

Version 0.1


Businesses Medical Military Recreational Schools

Table 5-5 Places Not Eligible for Display on Guide Signs Television and radio stations, motels, minor shopping centers, private businesses, petrol stations Private hospitals and clinics, mental hospitals, research facilities, nursing homes Bases or detachments, armories, arsenals Minor sports clubs and facilities, private and semipublic clubs (with the exception of public Municipal facilities and other than those specified in table 5-2) Elementary, secondary, vocational, trade, professional

To be effective, trailblazing must be restricted to limited destinations and/or to a limited extent. The Abu Dhabi guide sign system has five types of trailblazing signing: • • • •

Each individual letter or number within these fonts is positioned on a background tile. The use of these “tiles” automatically provides the correct spacing between letters and vertical spacing between rows of text.

Abu Dhabi International Airport. City center (central business district) Numbered routes. - Emirate Routes. - Abu Dhabi Routes. Supplemental Locations

5.2.2 AMOUNT OF LEGEND A significant factor in the design of guide signs, and in particular direction signs, is the amount of information to be provided. This factor is significant because:

A detailed explanation of the Abu Dhabi trailblazing requirements is contained in Section 5.4.

•

5.2

•

GENERAL STANDARDS FOR GUIDE SIGNS

In terms of all the other actions drivers have to take in order to navigate their vehicles safely through the street network, the amount of time available to read guide sign messages is commonly very limited.

5.2.1 LANGUAGE AND LETTERING STYLES Most signs in the guide sign class display their message in the form of arrows, symbols, and/or text. Guide sign “text” may include any of the following messages: • • • • • •

The more information that is required to be provided on guide signs the larger they have to be made. This in turn makes it more difficult to position the signs so that drivers can see them in time to read them and react to the information safely.

A destination name (control, supplemental, or local). A street name. A place name (Emirate, city, town, or community). A route number (only within a route number emblem). A distance to an exit. A distance to a destination.

In order to design a safe, efficient and cost-effective guide sign system it is therefore desirable to minimize the amount of information on signs: • •

All destination names, street names, place names, and distances should appear on guide signs in both Arabic and English.

To reduce reading times, and To reduce the size of signs.

For the guide sign system to be effective the information provided must be adequate for the navigational needs of the majority of drivers. It is difficult to predict the information needs of all drivers, particularly when it is not known what information drivers have when they start their

The style of lettering used should be Abu Dhabi Municipality standard Arabic and English fonts.

Version 0.1

Drivers must have enough time to read the given information, and The amount of information given dictates the ultimate size of the sign needed to display it.

5-8


•

journeys. In order to best cater for these needs a system of well known control destinations has been evolved and the most important routes have been allocated numbers (see Section 5.1).

•

The standard amount of legend to be displayed on EXIT DIRECTION signs is limited to:

The objective in numbering routes is to simplify the transfer of information and reduce the amount of information that needs to be transferred in order to achieve effective navigation. Information is also displayed in a consistent manner on direction signs so that the time required for the information search process is minimized.

• •

Symbols are also used to reduce the amount of text needed to describe certain destinations such as “the city center” and “the airport” and thereby reduce search time, reading times and recognition time. Symbols are particularly used with this objective on supplemental destination signs.

•

The majority of information used in the navigation process appears as legend on direction signs. There are two main categories of direction sign, namely those used for at-grade junctions and those used for grade-separated junctions.

• •

•

One arrow for each exit lane. A route number emblem of the route to which the exit leads (two may be displayed when the junction occurs at a point where the left and right turns are onto differently numbered routes). The name of one control destination to the right and one to the left (each destination in both Arabic and English).

The ONGOING DIRECTION signs display the following standard amount of information:

• •

Navigational information is given for a standard at-grade junction on stack type advance direction signs. These signs have a stack for each direction through the junction. The stacks may be arranged vertically, one above the other, for ground mounted signs and horizontally side-by-side for overhead signs. The standard amount of legend to be displayed in each stack is limited to: • • •

EXIT DIRECTION signs (advance exit signs and exit signs). ONGOING DIRECTION signs.

One arrow per ongoing lane. The route number emblem of the ongoing route. The name of the control destination for the route. One intermediate destination name in Arabic and English.

From time to time these limitations on the amount of legend may seem unreasonable. Pressure to ignore the limits should be resisted because information, once displayed, must be carried through subsequent junctions until the destination in question is reached. This means that the effect of an extra destination name is rarely limited to one junction but in fact spreads to several. If additional destinations are introduced in several places the likelihood is that they will accumulate at common points in the network resulting in unmanageable amounts of legend.

One arrow. One route number emblem. One control destination name in both Arabic and English. One intermediate destination name in both Arabic and English.

However, site-specific conditions may require a departure from these parameters and guidelines. Such variations can only be implemented with the prior approval of Abu Dhabi Municipality Road Department.

The same amount of information given on each stack that relates to a turning movement is repeated at the exits from the junction on chevron signs. The direction signs used for grade-separated junctions are mounted in an overhead position. Since the turning movement from each road normally involves a high-speed exit, the navigation information is given on two basic types of direction signs:

5.2.3 SIZE OF LETTERING Before drivers can read the legend on a guide sign they first have to see the sign. This function

5-9

Version 0.1


of the effectiveness of the visibility of traffic signs generally is referred to as their conspicuity. Conspicuity, and therefore the likelihood of detection of a guide sign is affected by:

using a larger letter size which makes the letters legible earlier while maintaining the same cut-off to the reading time when the observation angle limit is reached.

• • •

The legibility of the lettering (and symbols) used on guide signs and particularly direction signs is affected by the following factors:

• •

•

The size, shape, and color of the sign. The “brightness” of the sign. The contrast between the sign and its environment. The location of the sign in relation to the line of sight of the driver. The time a driver needs, and actually has available, to search for the sign in terms of road geometry, vehicle speed, traffic volumes, the presence of other signs, and other competing visual stimuli. The angle of the driver’s line of sight to the sign.

• • • • • •

Once a sign has been detected its long range attributes allow for its identification and function recognition. The “brightness” of a sign is termed its luminance. Guide signs need to have adequate luminance both by day and by night. Night-time luminance is improved by the use of retroreflective materials. Retroreflective materials have the property of redirecting a large percentage of the incident light back towards the light source (A nonretroreflective surface will reflect the light in all directions). Therefore a guide sign surfaced with retroreflective material is capable of redirecting most of the light from vehicle headlights back towards the vehicle. The further a sign is offset, either horizontally or vertically from the path of a vehicle, the greater are the entrance and observation angles. Retroreflective materials are more effective at small entrance and observation angles (although new materials are improving this characteristic). This means that the sign legend needs to be legible at small observation angles which, in turn, means at some distance from the sign. This requirement affects the size of lettering and symbols used for the legend. It also means that there is a closer point, still some distance from the sign, after which it is considered that the observation angle is too great and legibility is no longer effective. These sign characteristics affect the time for which the sign may be observed, and therefore for which it may be readable, within the time between when the lettering becomes legible and when the observation angle becomes too great. This time can be extended by Version 0.1

• • • •

The sign mounting position, i.e., ground mounted or overhead. The sign mounting height. The letter style, spacing, size, and stroke width. The legibility factor (0.6 meters of legibility distance per millimeter of lowercase ‘x’ letter height”). The visual acuity of drivers. The driver’s workload and surrounding distractions that compete for his attention. The approach speed of traffic. The amount of information displayed on the sign. The luminance (daytime) and retroreflectivity (night-time) contrast ratio between the sign legend and sign background. The ambient light levels (particularly street and advertising lighting).

Legibility can be defined simply as the ability to read a text message or accurately determine the form of a symbolic message. In this respect, for the long-range legibility required by drivers, the most critical element must be the smallest or thinnest element. This critical design element can be one or all of the following: • • • •

Letter font style. Letter stroke width. Letter and line spacing. Fine details of a symbol.

If all other factors are constant, as a general rule, increasing the size of the critical element will increase the legibility distance of the sign message. Typically the finest or most critical element for guide sign lettering is the stroke width. There are several letter styles which have been designed with characteristics required for use on a direction sign. These characteristics are: 5-10


• • • • •

Consistent letter design. Improved legibility over more “creative” styles. Widely recognized at an international level. Greater surface area and therefore target value. Usable with higher grades of retroreflective material with minimal risk of “overglow” or “bleeding.”

millimeters high and Arabic letters based on an aleph 140 millimeters high can be read by the normal driver from 60 meters. Legibility distances are conventionally quoted in relation to the lowercase or “x” height of letter because these constitute the majority of letters used on direction signs. These parameters are subject to ongoing research but the values accepted are consistent with those used in many other countries. However, it should be noted that some drivers may have poor visual acuity and that the legibility index at night can be lower than 0.6 m/mm. Under these circumstances lower legibility distances will result.

The Arabic and English letter styles specified in this manual maximize the above characteristics. The following are the more important dimensional characteristics of lettering based on the “x,” or lowercase, English letter height: • • • • • •

Another factor that affects the legibility of letters on direction and other guide signs is the luminance contrast between the lettering and the sign background. This contrast is expressed as a ratio of light-to-dark color luminance and is appropriate during both day and night. Ideally the contrast ratio should be between the ratios of 5 to 1 and 10 to 1. For symbolic signs with bold symbols the ratio may be as low as 4 to 1 and still be effective. Ratios higher than 10 to 1 run the risk of creating an “overglow” or “bleeding” effect from retroreflective materials at night, particularly if the background color is light and the letter color is dark. “Overglow” results in the letter stroke width of a dark letter being diminished by the glare from the bright color background. This in turn may affect the letter legibility. High ambient light levels common under street lighting will reduce this effect significantly and it is less problematic

Lowercase letter height = 1.0x Stroke width = 0.2x Uppercase letter height = 1.4x English text background tile height = 2.0x Aleph height of equivalent Arabic text = 1.4x Arabic text background tile height = 2.8x

For a given letter style and letter height a driver with a normal visual acuity of 1 (visual acuity is a measure of a driver’s ability to focus on fine objects) will be able to read the letters at a specific distance. This distance is known as the legibility distance. For the purpose of determining the letter sizes recommended in Table 5-6, a legibility index of 0.6 meters of legibility distance per millimeter of lowercase “x” letter height has been adopted for English and Arabic letters and characters. This means that English letters 100

Table 5-6 Recommended “x” Height for Guide Signs (millimeters) Posted Speed 100 km/h 80 km/h 60km/h 40 km/h Primary Guide Sign Overhead 300 250 200 200 Ground Mounted 250 200 150 100 Supplemental Sign Stack 250 150 100 100 Symbol Only 250 150 125 100 Gore Exit Sign 250 200 200 N/A Chevron Sign (see Note) At Roundabout 125 100 100 75 At Intersection 125 125 100 100 Route Marker 250 150 150 150 General Information Sign 150 150 100 100 Note: The above sizes apply for Abu Dhabi Routes only. Chevron signs placed on Emirates Routes should be increased in size by 20%.

5-11

Version 0.1


S

15º

Reading Time/ Distance

x=0.463 V(0.32 N-0.21) D+6.22 s Detail 5-2-1: Side Mounted Sign

h 7º

Reading Time/ Distance

x=0.463 V(0.32 N-0.21) D+13.57 h-14.25 Detail 5-2-2: Overhead Mounted Sign

Where: x = minimum “x” height required for legibility, in millimeters. V = posted speed or 85th percentile speed of roadway, in km/h. N = total units of information on a sign or sign grouping measured as follows: words up to 8 letters = 1 unit each word words more than 8 letters = 2 units each word individual arrow = 0.25 units each arrow map type arrow = 1 unit emblem, symbol, or distance = 0.5 units each item D = distraction factor between 1.0 for rural/low volume roads and 1.5 for urban/high volume roads. s = lateral distance from center of furthest driving lane to center of side mounted sign, in meters. h = vertical distance from pavement level to center of overhead mounted sign, in meters. Figure 5-2 Principles Of Legibility

Version 0.1

5-12


when vehicle headlights are commonly used in the low beam position (as under street lighting).

A. Side space between border and right or left line of justification = 0.5x B. Minimum lateral space between a route number emblem and an arrow = 1.0x C. Minimum lateral space between text and a Type 5 or Type 8 arrow = 1.0x D. Minimum lateral space between text and a symbol or emblem = 0.5x E. Vertical space between the top border and nearest legend = 0.5x F. Vertical space between the bottom border and nearest legend = 0.5x G. Vertical space between an upper row of legend and a lower row of legend on a horizontal stack type sign = 0.5x

Taking into consideration all the factors given above, including the standardization of the amount of destination display referred to in Section 5.2.2, a range of standard letter sizes has been derived for various guide sign applications. These sizes are listed in Table 5-6 and should be adhered to. If the amount of information to be displayed on a sign face is increased or it is necessary, due to exceptional geometric conditions, that the sign must be legible from a greater distance, consideration must be given to the need to use a larger-than-standard letter size and approval obtained from the Abu Dhabi Municipality Road Department. Figure 5-2 summarizes, in equation form, the principles for determining required letter height based on legibility and reading time criteria.

The vertical space between Arabic and English text, or between two rows of Arabic or two rows of English text, is dictated by the letter and number tiles and no additional internal spacing is required.

5.2.4 SIGN BORDERS

The horizontal spacing between letters or numbers is also controlled by the letter and number tiles which include the provision of a blank tile 0.5x wide for use between consecutive words in a line.

All guide signs should be provided with a contrasting border around the perimeter of the sign with the exception that when an exclusive exitonly white panel is placed at the bottom of an overhead exit direction sign no border is required on the white panel. The border color should be the same as the color used for place name lettering on the sign.

5.2.6 ARROWS The following basic types of arrows are used on guide signs:

Sign borders should have the following dimensional characteristics where “x” is the height of the lowercase lettering used for the sign: • •

• • • •

Width = 0.25x. Corner radius = 1.0x (to the outer edge of the border).

Chevron arrow. Stack-type arrow. Overhead arrows. Map-type arrow.

An internal dividing border should be used to separate the stacks of a stack type direction sign. This border should have the same width as the outside sign border but should not be provided with radii where it joins the outside border.

The individual types of arrow are detailed below. All arrows have been allocated a “Type” number including left and right applications. The arrows should appear in white unless noted otherwise. The standard applications of arrows Type 1 to Type 8 are illustrated in Figure 5-4.

5.2.5 INTERNAL SPACING

5.2.6.1

The sign face layout of all guide signs should adhere to the internal spacings listed below and illustrated in a typical example in Figure 5-3:

Chevron Arrows Types 1 and 2 are used on CHEVRON DIRECTION sign 515 to indicate

5-13

CHEVRON ARROW TYPES 1 AND 2

Version 0.1


0.25x

R=1.0x 0.5x

= 5.8x

4.0x

Arrow Type 3

Arabic

Route Marker

2.8x 2.0x

English =

0.25x

0.5x 0.5x

=

5.8x

4.0x

Arrow Type 4

Arabic

Route Marker

2.8x

English

2.0x

=

0.25x

0.5x

=

5.8x

=

0.5x

2.8x

Route Marker

4.0x

English

Arabic

Arrow Type 5

4.0x

2.0x

=

0.25x

=

3.5x 0.5x

x

3.0x

x 0.5x

3.5x

0.25x

0.5x

Figure 5-3 Typical Guidesign Internal Spacing Elements

the action point for a left or right turn at an atgrade junction. 5.2.6.2

ADVANCE VERTICAL STACK sign 512, and ADVANCE SUPPLEMENTAL sign 514 to indicate the direction in which drivers must turn at the junction ahead in order to reach the destination named in the stack in which the arrow is located.

STACK SIGN ARROW TYPE 3

Stack Sign Arrow Type 3 should only be used pointing straight upwards. The arrow is used on ADVANCE HORIZONTAL STACK sign 511 and ADVANCE VERTICAL STACK sign 512 to indicate that drivers must travel straight-on through the junction ahead to reach the destination named in the stack. When used on sign 512 a Type 3 arrow should only be used in the top stack.

However, certain site specific conditions may require a departure from these parameters and guidelines. Such variations may only be implemented with the prior approval of Abu Dhabi Municipality Road Department. 5.2.6.4

However, certain site-specific conditions may require a departure from these parameters and guidelines. Such variations may only be implemented with the prior approval of Abu Dhabi Municipality Road Department. 5.2.6.3

Stack Sign Arrow Type 6 should only be used pointing to the left. The arrow is used on ADVANCE SUPPLEMENTAL sign 514 to indicate that drivers must execute a U-turn at the next opportunity in order to reach the destination named in the stack. In such an instance drivers are likely to see a further sign 514 shortly after the U-turn indicating a right turn into a side road.

STACK SIGN ARROW TYPES 4 AND 5

Stack Sign Arrows Types 4 and 5 may be used on ADVANCE HORIZONTAL STACK sign 511, Version 0.1

STACK SIGN ARROW TYPE 6

5-14


Type 1

Type 2

Chevron Direction Signs

Type 3

Type 3

Type 3

Type 4

Type 4

Type 5

Type 4

Type 5

Type 5 Type 5

Type 6

Type 4

Stack Direction Signs and Trailblazer Signs

Type 7

Type 7

Type 7

Type 7

Type 7

Type 8

Type 8

Type 8

Advance Exit Direction Signs

Type 8

Type 8

Exit Direction Signs

Type 7

Type 7

Overhead On-Going Direction Signs

Type 9 Type 8

Type 8 Type 8

Map Direction Sign

Gore Exit Signs

Supplemental Exit Sign

Note : Type 8 arrow may be right or left pointing to suit application conditions.

Figure 5-4 Arrow-Type Applications

5-15

Version 0.1


Type 1

Type 3

Type 2

Type 4

Type 5

Type 7

Type 6

Version 0.1

5-16


5.2.6.5

DOWNWARD POINTING ARROW TYPE 7

Downward Pointing Arrow Type 7 should only be used on an overhead direction sign at the bottom of the sign pointing straight downwards. The arrow is used on ADVANCE EXIT DIRECTION sign 551 and ONGOING DIRECTION sign 553 to indicate that drivers may use the lane over which the arrow is centered to reach the destination, or one of the destinations, named in the sign above the arrow. When signs 553 and 551 are mounted next to each other there should be one Type 7 arrow centered over each lane. If one lane is a shared exit lane and ongoing lane the arrow over the lane should appear on the ADVANCE EXIT DIRECTION sign 551. If one or more of the lanes indicated on sign 551 is an exclusive exit lane (in other words the lane is dropped from the ongoing path) the Type 7 arrow should appear in black on a white background panel at the bottom of the sign together with the word “ONLY” in Arabic and English. 5.2.6.6

Type 8

The Type 8 arrow may also be used on ground mounted SUPPLEMENTAL EXIT sign 557 on a freeway to indicate that the high speed exit a short distance ahead may be used to reach the supplemental destination named on the sign. Left hand exits from a through route are to be avoided. However, where such do occur, the Type 8 arrow should be inclined towards the left and moved to the left side of ground mounted signs.

UPWARD POINTING ARROW TYPE 8

5.2.6.7

MAP ARROW TYPE 9

Map Arrow Type 9 should only be used pointing straight upwards so that the entry path to the diagram is located at the bottom of the sign. The arrow may only be used on ADVANCE MAP sign 513 to indicate to drivers that the roundabout junction ahead has more than four exit roadways and/or is of an irregular shape.

Upward Pointing Arrow Type 8 may be used on a ground mounted or overhead exit direction sign. The arrow should be located on the right side of ground mounted signs and at the bottom of overhead signs. The arrow is used on an overhead EXIT DIRECTION sign 552 to indicate to drivers that use of the lane or lanes over which the arrow is located will allow them to leave the grade-separated route by means of a high speed exit to reach the destination, or one of the destinations, named on the sign above the arrow. If one or more of the lanes indicated on sign 552 is an exclusive exit lane the Type 8 arrow should appear in black on a white background panel at the bottom of the sign together with the word “ONLY” in Arabic and English. The Type 8 arrow is also used on ground mounted GORE EXIT signs 554, 555 and 556 to indicate to drivers the action point for the high speed exit.

Type 9

5-17

Version 0.1


Map Arrow Type 9 should be custom designed to suit the geometric configuration of the junction it describes.

5.2.7 ROUTE NUMBER EMBLEMS There are two types of numbered routes, namely: • •

Emirate Routes which may extend from one emirate to another or may connect towns and cities within an emirate, and Abu Dhabi Routes, which lie primarily within the Abu Dhabi urban area and/or provide significant access to Emirate Routes. guidelines. Such variations may only be implemented with the prior approval of Abu Dhabi Municipality Road Department.

The different routes are identified on the relevant direction and route marker signs by exclusive route number emblems. The number of the route is indicated within the emblem so that the route identification is located at the top of the emblem in English and Arabic and the route number located below these letters in English numerals only. The overall sizes of the emblems are 4 “x” high by 3 “x” wide. 5.2.7.1

The Emirate Route Emblem should have a white background, a blue icon, and yellow text. 5.2.7.2

The Abu Dhabi Route emblem should appear on all ADVANCE HORIZONTAL STACK signs 511, ADVANCE VERTICAL STACK signs 512, ADVANCE EXIT DIRECTION signs 551, EXIT DIRECTION signs 552, ONGOING DIRECTION signs 553, CHEVRON DIRECTION signs 515, ABU DHABI ROUTE MARKER signs 502 and ABU DHABI ROUTE TRAILBLAZER signs 506, which indicate an approved control destination on an Abu Dhabi Route. The emblem should always have a green background within a white frame and the route identification letters and the route number should be yellow.

EMIRATE ROUTE EMBLEM

The Emirate Route emblem should appear on all ADVANCE HORIZONTAL STACK signs 511, ADVANCE VERTICAL STACK signs 512, ADVANCE EXIT DIRECTION signs 551, EXIT DIRECTION signs 552, ONGOING DIRECTION signs 553, CHEVRON DIRECTION signs 515, EMIRATE ROUTE MARKER signs 501, and EMIRATE ROUTE TRAILBLAZER signs 505, which indicate an approved control destination on an Emirate Route. The emblem should always have a blue background within a white frame and the route identification letters and the route number should be yellow.

The emblem should always be to the left of the destination name except on ADVANCE HORIZONTAL STACK sign 511 when the emblem should share the top row of the sign with the appropriate stack-sign arrow.

The emblem should always be to the left of the destination name except on ADVANCE HORIZONTAL STACK sign 511 when the emblem should share the top row of the sign with the appropriate stack-sign arrow (see Sections 5.5 and 5.6 for examples of typical guide signs showing route number emblems).

Certain site-specific conditions may require a departure from these parameters and guidelines. Such variations may only be implemented with the prior approval of Abu Dhabi Municipality Road Department.

However, certain site specific conditions may require a departure from these parameters and

Version 0.1

ABU DHABI ROUTE EMBLEM

5-18


Approval for the signing of any five-star hotel must be obtained from Abu Dhabi Municipality Road Department prior to implementation.

THIS SPACE RESERVED FOR ABU DHABI EMIRATE ROUTE SIGN

Any new supplemental symbols that may be designed from time to time should embody the principles described in Section 5.2.3. The use of thin critical elements and fine detail should be avoided as this will not assist long range recognition of the symbol.

5.3

ROUTE MARKER SIGNS

5.3.1 USE OF ROUTE MARKER

5.2.8 SUPPLEMENTAL DESTINATION SIGN SYMBOLS

A route marker sign is a confirmatory guide sign that provides reassurance to motorists that they are on their intended route (or conversely to advise them that they have taken a wrong turn and are not on the route that they planned to be on).

Supplemental destination signs may be used to present additional guidance information to drivers as and when this may be warranted (see Section 5.1). As a result, supplemental destination signs are only used occasionally. The information displayed therefore does not relate to approved orientational control destinations which appear on normal direction signs.

Under the Abu Dhabi guide signing system the ongoing routes at all intersections will be signed with the route number as part of the primary advance guide signing. This is true for at-grade junctions (signalized intersections and roundabouts) and for grade-separated interchanges. Thus, every time a motorist traveling on a route approaches a junction, he will receive confirmation of the route he is on.

The most common application of supplemental destination signs is to display information related to tourist destinations. See Table 5-2 for a list of locations eligible for supplemental destination signing.

As such, route marker signs are not required to be used after every junction, but only when the distance between junctions is considerable. On rural roads where junctions with numbered routes are infrequent, a route marker should be erected if the distance between primary guide signs containing the emblem of the ongoing route are spaced more than two kilometers apart. In such a case a route marker should be erected approximately two kilometers after the junction, and every 10 kilometers thereafter, up to a point not less than two kilometers before the next primary guide sign that contains the emblem of the ongoing route.

The symbols approved for use on supplemental destination signs are illustrated in Figure 5-5. The symbol should appear on the left side of the sign and should be followed by the destination’s full name in Arabic and English irrespective of the direction indicated by the arrow. Thus if a specific beach is to be identified it should be displayed in the form: “symbol” Al Raha Beach The symbol should be provided in black on a square white background. Some approved supplemental destinations do not have a corresponding symbol and should be signed using only Arabic and English text.

On urban roadways where there is more turning traffic at major junctions as well as more entering traffic from minor roads between major junctions, a more frequent spacing of route markers is desirable. On urban roads a route marker should

5-19

Version 0.1


Golf Course

Horse Racing

Camel Racing

Zoo

Beach Park

Marina

Theme Park

Garden/ Park/ Picnic Site

Youth Hostel

Camping Site

Fort/ Museum

Tourist Information

Camping/ Caravan Site

Figure 5-5 Approved Supplemental Destination Symbols

be erected if the distance between primary guide signs containing the emblem of the through route are located more than two kilometers apart. In such a case a route marker should be erected approximately 500 meters after the junction, and every two kilometers thereafter, up to a point not less than one kilometer from the next primary guide sign that contains the emblem of the through route.

5.3.2 EMIRATE ROUTE MARKER SIGN 501 EMIRATE ROUTE MARKER sign 501 should be the Emirate Route emblem as described in Section 5.2.7.1, mounted alone. The sign should be 3.0 “x” wide by 4.0 “x” high and with an “x” height as given in Section 5.2.3.

5.3.3 ABU DHABI ROUTE MARKER SIGN 502

Figure 5-6 illustrates both of the above principles.

ABU DHABI ROUTE MARKER sign 502 should be the Abu Dhabi Route emblem as described in Section 5.2.7.2, mounted alone. The

Version 0.1

5-20


2km

Repeat every 10km

2km min

More than 5km

Detail 5-6-1: Rural Route Marker Placement

500m

Repeat every 2km

1km min

More than 2km Detail 5-6-2: Urban Route Marker Placement

Primary Guide Sign Containing Route Emblem Of Through Route

Route Marker Signs 501 or 502

Figure 5-6 Use of Route Marker Signs

5-21

Version 0.1


• • • • •

An Emirate Route (by number). An Abu Dhabi Route (by number). A supplemental (tourist or service) destination. A freeway. A parking area.

While all of these destinations may appear on primary or supplemental direction signs there are occasions when it may be necessary to indicate the direction to such a type of destination when the use of normal direction signs is not appropriate, or impossible due to space limitations. Sign 501

Trailblazing signs display only a stack type arrow, one of Types 3, 4, 5 or 6 together with a symbol. (When geometric conditions require, an upward pointing slanted arrow may be used. A Type 3 arrow placed at 45 degrees is suitable for this purpose.) The signs should be located in advance of an intersection, roundabout or recognized U-turning lane. They will normally be used to indicate a turn but, in the event that drivers may be confused, for whatever reason, about the correct direction to take, an ongoing indication may be given, when appropriate, using a Type 3 arrow. The signs should preferably not be used in addition to normal direction signs at a junction although in one or two specific instances this may be acceptable.

THIS SPACE RESERVED FOR SIGN 502

Sign 502

Once a trailblazing sign has been used, further trailblazing signs must be provided at all decision points until the destination indicated has been reached, or until the message concerned becomes part of the information displayed by the normal control-destination-based guide-sign system.

sign should be 3.0 “x” wide by 4.0 “x” high and with an “x” height as given in Section 5.2.3.

5.4

TRAILBLAZING SIGNS

5.4.1 USE OF TRAILBLAZING

There are specific circumstances for each of the types of trailblazer identified above in terms of which an appropriate trailblazing sign may be used. These circumstances are detailed in the following sections.

“Trailblazing” is used to provide a localized supplement to the control destination based guidesign system. The concept of trailblazing can be applied to a specific destination or type of destination and it may even be applied to direct drivers towards a route. The concept involves providing strategically located compact supplemental stack type trailblazing signs to indicate to drivers the direction to be taken in order to reach one of the following specific types of destination: • •

The trailblazer signs that follow should have blue, green, or white background color appropriate for the type of route which they are located.

Airport. City center.

Version 0.1

5-22


5.4.2 AIRPORT TRAILBLAZER SIGN 503

5.4.3 CITY CENTER TRAILBLAZER SIGN 504

AIRPORT TRAILBLAZING sign 503 is likely to be the most widely used trailblazer sign. The sign may be used to direct drivers from areas commonly frequented by visitors to Abu Dhabi towards the airport. The sign should be used in a similar manner to ADVANCE SUPPLEMENTAL sign 514 (see Section 5.5.5). Sign 503 may be used on an Emirate Route, an Abu Dhabi Route, or a lesser unnumbered route. It therefore may be used with or without normal control destination direction signs, unless such a direction sign already has the Airport as a trailblaze symbol. Once sign 503 has been used it should continue to be provided at all decision points unless the symbol appears on a direction sign.

CITY CENTER TRAILBLAZER sign 504 may be used within the general environs of the Abu Dhabi city center, i.e., at a local level, to direct drivers towards what is considered to be the popular core of the business area. As such, the sign may only be displayed after the city center message has appeared as a control destination on direction signs.

Sign 504

Sign 504 should be located in a side mounted position on the right side of the pavement, up to 160 meters from the junction, with due regard to the position of any other direction signs and any other minor side road intersections.

Sign 503

5.4.4 EMIRATE ROUTE TRAILBLAZER SIGN 505

The AIRPORT TRAILBLAZER sign should be located in a side-mounted position on the right side of the roadway, up to 160 meters from the junction, with due regard to the position of any other direction signs and any minor road intersections. When the sign is for a left turn movement from a divided roadway it may be beneficial to locate the sign on the median island, particularly if a U-turn movement is called for. The Airport symbol should be positioned on sign 503 so that it “points” in the same direction as the arrow used on the sign.

EMIRATE ROUTE TRAILBLAZER sign 505 may be used to direct drivers towards an Emirate Route when direction signs are not otherwise in use or appropriate. Since Emirate Routes have limited points of access it may occasionally be necessary to assist drivers in finding a route or street which intersects with the Emirate Route. Sign 505 should therefore only be used at a local level to assist drivers in finding their way upwards in the street network. Once used the sign should be repeated at decision points until such time as the appropriate Emirate Route emblem appears on a normal Advance Direction sign with the appropriate control destinations. It may also be beneficial to use sign 505 on a route which is parallel to an Emirate Route.

The Airport symbol may also be used as a trailblazing component on primary direction signs. See each specific sign for use locations.

The sign should be located in a side-mounted position on the right side of the roadway, up to

5-23

Version 0.1


The sign should be located in a side-mounted position on the right side of the street, up to 160 meters from the junction, with due regard to the position of any other direction signs and any minor side road intersections. The route emblem displayed on the sign should include the specific number of the Abu Dhabi Route being trailblazed.

5.4.6 SUPPLEMENTAL DESTINATION TRAILBLAZER SIGN 507 Sign 505

A SUPPLEMENTAL DESTINATION TRAILBLAZER sign 507 may be used to carry on a basic supplemental destination message which has already appeared on an ADVANCE SUPPLEMENTAL sign 514. Once a supplemental message has been given by sign 514, in the form of an approved supplemental symbol plus the primary name of the facility (Section 5.5.5), subsequent signs at decision points up to the final turn to the facility should be trailblazer sign 507.

160 meters from the junction, with due regard to the position of any other direction signs and any minor side road intersections. The Emirate Route Emblem displayed on sign 505 should include the specific number of the Emirate Route being trailblazed.

5.4.5 ABU DHABI ROUTE TRAILBLAZER SIGN 506 ABU DHABI ROUTE TRAILBLAZER sign 506 may be used to direct drivers towards a numbered Abu Dhabi Route when direction signs are not otherwise in use or appropriate. Sign 506 should therefore only be used at a local level within a community to assist drivers in finding their way upwards in the street network. However, there are some instances where exceptions to this rule can be permitted. The most notable exception would be on the approach to a minor junction with an unnumbered route where the driver merely requires a confirmation that the Abu Dhabi Route continues in a straight ahead direction. The use of sign 506 may be particularly appropriate within a community when there is some facility of importance which tends to attract visitors from outside the community.

Sign 507

The signs should be located in a side-mounted position on the right side of the roadway, up to 160 meters from the junction, with due regard to the position of any other direction signs and any minor side road intersections. When the sign is for a left turn movement from a divided roadway it may be beneficial to locate the sign on the median island, particularly if a U-turn is called for. In this latter case a Type 6 arrow should be used. The symbol or symbols (maximum of two) displayed on the sign should only be approved supplementary destination symbols (see Figure 5-5) which have appeared on one or more preceding ADVANCE SUPPLEMENTAL signs 514. In other words, additional supplemental symbols should not be introduced using sign 507 without prior appearance on sign 514.

RESERVED FOR SIGN 506

Sign 506

Version 0.1

5-24


5.4.7 FREEWAY TRAILBLAZER SIGN 508 A FREEWAY TRAILBLAZER sign 508 may be used as a general trailblazer sign indicating a direction which may be taken in order to intersect and join a freeway. Sign 508 may be used as an alternative to EMIRATE ROUTE TRAILBLAZER sign 505 when the use of the latter sign might cause confusion with other Emirate Route Emblems on other guide signs. The use of sign 508 is appropriate at a local level or on Abu Dhabi Routes, particularly in an area close to a freeway and when the route or street concerned runs more or less parallel to the freeway.

Sign 509

5.5

AT-GRADE JUNCTION SIGNS

5.5.1 TYPES OF AT-GRADE JUNCTION SIGNS The following types of guide sign may be specified for use in advance of, at, or within at-grade junctions: • •

Sign 508

• • • •

The signs should be located in a side-mounted position on the right side of the roadway, up to 160 meters from the junction, with due regard to the position of any other direction signs and any minor side road intersections. When the sign is for a left-turn movement from a divided roadway it may be beneficial to locate the sign on the median island, particularly if a U-turn is called for.

ADVANCE HORIZONTAL STACK sign (overhead mounted), or ADVANCE VERTICAL STACK SIGN (ground mounted), or ADVANCE MAP sign. ADVANCE SUPPLEMENTAL sign. CHEVRON DIRECTION sign. STREET NAME sign.

All approaches to junctions between two Emirate or Abu Dhabi routes should be provided with each of the above sign types with the exception of the ADVANCE SUPPLEMENTAL sign, which is optional. Details of the signs, their functions, applications, locations, and the information that may be displayed are given in the following sections.

The sign should comprise the appropriate Type 3, 4, or 5 arrow together with the “Freeway” symbol in black on a white square background in a similar manner to signs 503, 504, and 507. When a Uturn is required a Type 6 arrow should be used.

However, certain site-specific conditions may require a departure from the parameters and guidelines specified in the following sections. Such variations can only be implemented with the prior approval of Abu Dhabi Municipality Road Department.

5.4.8 PARKING TRAILBLAZER SIGN 509 PARKING TRAILBLAZER sign 509 may be used locally to direct drivers towards a designated parking area or car park.

5-25

Version 0.1


5.5.2 ADVANCE HORIZONTAL STACK SIGN 511 5.5.2.1 •

•

5.5.2.4

Only the following items are eligible for display on ADVANCE HORIZONTAL STACK signs:

FUNCTION

• • • • •

To indicate the routes and control destinations at the end of each route and intermediate destinations, where applicable, that can be reached by turning left or right, or continuing ahead. To assist drivers in selecting the most appropriate lanes for the maneuvers they wish to make at the junction ahead.

5.5.2.2

•

Information relevant for changing direction to the left, going straight ahead, or changing direction to the right should be displayed in three separate stacks, arranged horizontally from left to right, for a crossroad or roundabout and in two separate stacks for a T-junction. The left-turn stack should always be leftmost and the right-turn stack the rightmost.

APPLICATION

In advance of signalized at-grade intersections. In advance of signalized or unsignalized roundabouts.

5.5.2.3 • • • •

•

Direction Arrow. Hooked Type 4 or 5 arrows facing in the appropriate direction should be displayed in the left and right turn stacks. An upward pointing Type 3 arrow should be placed in the ongoing movement stack.

LOCATION

Overhead on gantries (placed centrally over the roadway). Up to 250 meters in advance of the intersection or roundabout. With due regard to the position of any minor side road intersection. Not less than 175 meters after the previous junction of numbered routes.

Vertical placement: - At the top of the sign. Horizontal placement:

Sign 511

Version 0.1

Direction arrow. Route number emblem. Control destination/intermediate destination. City center symbol. Airport Symbol.

The items and their placement are described below.

As overhead signs on routes with traffic volumes and/or number of lanes warranting overhead advance signs as specified in Section 2.2.4 and as follows: •

DISPLAY OF INFORMATION

5-26


•

- Left turn and ongoing movement: left justified in stack. - Right turn: right justified in stack.

The symbol will be used only with a route that has Abu Dhabi city center as a control destination.

Route Number Emblem.

Vertical placement:

One route number emblem should be displayed for each direction of travel for which a route number has been allocated.

- Centered in each stack.

Vertical placement:

- Right justified in stack.

Horizontal placement:

•

- At the top of the sign.

The symbol will be used only on a route that is trailblazed to the airport.

Horizontal placement: - Left turn and ongoing movement: right justified in stack. - Right turn: left justified in stack. •

Airport symbol.

Placement: - Centered between the direction arrow and route number emblem in the top row.

Control destination. One control destination and one intermediate destination should be displayed for each direction of travel for which a route number has been allocated. If one of the turning movements does not have a route number and control destination, the street name or number should be substituted for the control destination.

5.5.3 ADVANCE VERTICAL STACK SIGN 512

Vertical placement:

•

5.5.3.1 •

- At the bottom of the sign, with Arabic legend above the English.

FUNCTION

To indicate the routes and control destinations at the end of each route that can be reached by turning left or right, or continuing ahead. To assist drivers in selecting the most appropriate lanes for the maneuvers they wish to make at the junction ahead.

5.5.3.2

APPLICATION

Horizontal placement: As side-mounted signs on routes with traffic volumes and/or a number of lanes that do not warrant overhead advance signs as specified in Section 2.2.4 and as follows:

- All stacks: Arabic text in the bottom row is right justified on the route number emblem or Type 5 arrow in the top row, and English text in the bottom row is left justified on the Types 3 or 4 arrows or route number emblem in the top row.

•

• •

In advance of signalized at-grade intersections. In advance of signalized or unsignalized roundabouts.

If a city center symbol is used it should be considered as an integral part of the relevant line of text. City center symbol.

5-27

Version 0.1


Sign 512

5.5.3.3 • • • •

LOCATION

appropriate direction should be displayed in the left and right turn stacks.

Ground mounted on the right side of the roadway. Up to 250 meters in advance of the intersection or roundabout. With due regard to the position of any minor side-road intersection. Not less than 175 meters after the previous junction of numbered routes.

5.5.3.4

Vertical placement: - Centered in each stack. Horizontal placement: - Ongoing and left turn: left justified in each stack. - Right turn: right justified in stack.


•

Only the following items are eligible for display on ADVANCE VERTICAL STACK signs: • • • • •

One route number emblem should be displayed for each direction of travel for which a route number has been allocated.

Direction arrow. Route number emblem. Control destination/intermediate destination. City center symbol. Airport Symbol.

Vertical placement: - Centered in each stack. Horizontal placement:


- Ongoing and left turn: left justified on Type 3 or Type 4 arrows (see Figure 5-3). - Right turn: left justified with route number emblem(s) in other stack(s) above.

Information relevant for going straight ahead or changing direction to the left or to the right should be displayed in three separate stacks, arranged vertically, from top to bottom, for a crossroad or roundabout, and in two separate stacks for a T-junction. The straight-ahead stack should always be uppermost and the right turn stack the lowermost. •

•

Control destination. One control destination and one intermediate destination where applicable should be displayed for each direction of travel for which a route number has been allocated. If one of the turning movements does not have a route number and control destination, the street name or number should be substituted for the control destination.

Direction arrow. An upward pointing Type 3 arrow should be placed in the ongoing movement stack. Hooked type 4 or 5 arrows facing in the

Version 0.1

Route number emblem.

5-28


Vertical placement:

5.5.4 ADVANCE MAP SIGN 513

- Centered in the stack with the Arabic legend above the English.

5.5.4.1 •

Horizontal placement: - All stacks: • Arabic text is right justified on right turn Type 5 arrow. If the sign does not require a right turn stack, as at a T-junction from the left, the Arabic text should be justified on the right edge of the sign. The English text is left justified on the route number emblems. •

FUNCTION

To indicate the routes and control destinations at the end of each route that can be reached by turning left or right or by continuing ahead. To assist drivers in selecting the most appropriate lanes for the maneuvers they wish to make at the junction ahead.

5.5.4.2

APPLICATION

As ground-mounted signs in advance of junctions with nonstandard or irregular geometry such as a roundabout that is enlarged into a noncircular shape and/or has more than four exit roadways. This type of sign should only be used in exceptional circumstances and will require a significant side space to accommodate its size.

City center symbol. - The symbol will only be used with a route that has Abu Dhabi City Center as a control destination.

5.5.4.3

LOCATION

Vertical placement: • - Centered in each stack. • Horizontal placement: •

•

Ground mounted on the right side of the roadway. Up to 250 meters in advance of the roundabout (or other junction; see section 5.5.4.4). With due regard to the position of any minor side road intersection. Not less than 175 meters after the previous junction of numbered routes.

- Ongoing and left turn: right justified in stack. - Right turn: Right justified on Type 5 arrow.

•

Airport symbol.

5.5.4.4

The symbol will be used only on a route that is trailblazed to the airport.

The following items only are eligible for display on ADVANCE MAP signs:

Placement:

• • • •

- Centered between the direction arrow and route number emblem in the top row.


Map direction arrow. Route number emblem. Control destination/intermediate destination. City center symbol.

Sign 513

5-29

Version 0.1



- Left-turn movement: justified on the left side of the sign. - Right-turn movement: left justified on the right turn arrow leg.

Information relevant to changing direction or going straight ahead should be displayed in line with the pointed arrow legs of the map Type 9 arrow representing an exit path from the junction. •

•

Control destination. One control destination and one intermediate destination where applicable should be displayed for each direction of travel for which a route number has been allocated. If one of the turning movements does not have a route number and control destination, the street name or number should be substituted for the control destination. If the control destinations in one direction are more than two destinations (e.g., A1 Sila, Qatar, Saudi Arabia, as can be found in Table 5-1), the sign should display only two of those control destinations along with an intermediate destination for a maximum of three destinations.

Map direction arrow. The map direction arrow Type 9 should represent the shape of the complex junction as closely as is practical with one pointed arrow leg for each exit path from the junction, EXCLUDING the reverse path to the direction of entry to the junction. (Although the example illustrated shows a form of roundabout other shapes of map direction arrow may be considered. In such a case the sign design should be customized to the specific map direction arrow shape following the general principles stated for the example.)

Vertical placement: Vertical placement: - Ongoing movement: above the relevant arrow legs with Arabic text over English text. - Left- and right-turn movement: centered on the left and right turn arrow legs respectively with Arabic text over English text.

- At the bottom of the sign. Horizontal placement: - In the middle of the sign between the right and left destinations. •

Horizontal placement: Route number emblem. - Ongoing movement: the block comprising the route number emblem and the Arabic and English text should be centered over the relevant arrow leg. If there should be more than one ongoing exit path from the junction the relevant blocks comprising the route number emblem and English and Arabic text should be moved off-center on the arrow legs until sufficient space exists between the two blocks that their proximity will not be confusing. - Left- and right-turn movements: left justified on the route number emblem (see below). - All movements: the English text should be left justified on the route number emblem and the Arabic text right justified on the right hand end of the English text, UNLESS the Arabic text is longer than the

One route number emblem should be displayed for each direction of travel for which a route number has been allocated. Vertical placement: - Ongoing movement: above and to the left of the relevant arrow leg(s) and centered vertically on the Arabic and English text (see also Control Destination). - Left- and right-turn movements: centered on the left and right turn arrow legs. Horizontal placement: - Ongoing movement: to the left of the control destination name.

Version 0.1

5-30


•

English text in which case both Arabic and English text should be left justified on the route number emblem. •

•

City center symbol.

5.5.5.3

The symbol will only be used with a route that has Abu Dhabi City Center as a control destination.

•

Placement: - To the right of the destination name and centered vertically on the Arabic and English legends. •

In advance of signalized or unsignalized roundabouts. In advance of a U-turn.

•

Airport symbol.

•

The symbol should not be used ordinarily on this sign. Separate trailblaze signing should be used.

LOCATION

Ground-mounted on the right side of the roadway UNLESS the sign is for a left turn or U-turn movement and the median island is wide enough to safely accommodate the sign, in which case the sign may be located on the left side of the roadway in a one-way roadway or dual carriageway. Up to 160 meters in advance of the intersection or roundabout between sign 511 (or 512 or 513) and the junction, or up to 160 meters in advance of the U-turn . With due regard to the provision of any minor side road intersection.

5.5.5.4


5.5.5 ADVANCE SUPPLEMENTAL SIGN 514

The following items only are eligible for display on Advance Supplemental signs:

5.5.5.1

• •

•

•

FUNCTION

To indicate approved supplemental destinations either in addition to standard advance direction signs, or on their own at junctions that do not warrant standard advance direction signs. To assist drivers who are unfamiliar with Abu Dhabi in finding their way from a numbered route to the non-control supplemental destination being sought.

5.5.5.2

•

The items and their placement are described below. Information will commonly be displayed in single left or right turn stack signs. Since the function of the sign does not include orientation, only the directions to approved supplemental destinations are signed. If more than one stack is required the stack order should be the same as for an ADVANCE VERTICAL STACK sign 512.

APPLICATION

As ground-mounted signs on routes in close proximity to the facility indicated on the sign as follows: •

Direction arrow. Approved supplemental sign symbol (see Section 5.2.8). Approved supplemental destination (“primary” or identifying name only).

•

In advance of signalized or unsignalized atgrade intersections.

Direction Arrow. Hooked type 4, 5, or 6 arrows facing in the appropriate direction should be displayed in the appropriate stack (an ongoing Type 3 arrow may be used for an ongoing indication in exceptional circumstances where confusion may otherwise occur).

Sign 514

5-31

Version 0.1


Vertical placement:

Vertical placement:

- Centered in each stack.

- One destination: centered in the stack with the Arabic text above the English text. - Two destinations of the same type: centered in the stack with the two Arabic names above the two English names. - Two destinations of different types: each destination centered on the appropriate supplemental symbol with the Arabic text above the English text for each destination.

Horizontal placement: - Left turn and U-turn: left justified in stack. - Right turn: right justified in stack. •

Approved supplemental sign symbol. The approved symbol (see Figure 5-5) should be used with the primary or identifying name for the facility. If more than one facility of the same type exists in one direction up to two names may be used with one symbol (see Approved Supplemental Destination below). Two different symbols, for two different types of supplemental destination, may be displayed with their appropriate primary names in one stack.

Horizontal placement: - Left turn and U-turn: Arabic text right justified on the right edge of the sign. English text left justified on the Supplemental Symbol. - Right turn: Arabic text right justified on the Type 5 arrow. English text left justified on the supplemental symbol.

Vertical placement:

5.5.6 CHEVRON DIRECTION SIGN 515

- One symbol: centered in the stack - Two symbols: aligned one above the other, centered in the stack so that the spaces between borders and symbols, and between symbols, are equal.

5.5.6.1 •

Horizontal placement: • - Left turn and U-turn: left justified on Type 4 and Type 6 arrows. - Right turn: left justified on edge of sign, UNLESS both left and right turn stacks are required, in which case both left and right stack symbols should be left justified on the Type 4 arrow in the left turn stack. •

•

To indicate the route number and control destination at the end of a route, at the point of turn onto the route (the action point). To indicate the point of turn towards a supplemental destination. To indicate the point of turn towards a local destination.

5.5.6.2

APPLICATION

As ground-mounted signs as follows:

Approved supplemental destination.

•

The full destination name should be used for all supplemental destinations, along with an approved supplementary symbol, where it is applicable. When two facilities of the same type occur in one direction, two names may be used with one symbol. If two different types of facility occur in one direction, two symbols may be provided within one stack so that one is above the other (see Approved Supplemental Sign Symbol, above).

•

Version 0.1

FUNCTION

•

For all exit paths from signalized or unsignalized roundabouts. For the left and right turn exit paths from a signalized intersection. For supplemental or local exit paths at minor junctions.

5.5.6.3 •

5-32

LOCATION

Ground mounted on the right side of the roadway for all right turn movements.


Sign 515

• •

•

Ground mounted on the far left side of a signalized intersection for left turn movements. Ground mounted on the right side of the roadway for left turn movements without a turning lane and/or for minor intersecting roads. Within the gore area of right turning slip roads.

Chevron Type 1 or 2 arrows facing in the appropriate direction should be displayed in left and right turn signs. Vertical placement: - Centered on the sign. Horizontal placement:

5.5.6.4

DISPLAY OF INFORMATION - Right turn: right justified on the sign. - Left turn: left justified on the sign.

The following items only are eligible for display on CHEVRON DIRECTION signs: • • • • • • •

•

Direction arrow. Route number emblem. Control destination/intermediate destination. Supplemental symbol and destination. City center symbol. Airport symbol. Local destination.

Route number emblem. One route number emblem should be displayed when a route number has been allocated. Vertical placement: - Centered on the sign.



Information relevant for changing direction to the right or left should be displayed singly in individual CHEVRON DIRECTION signs. •

- Right turn: left justified on the left edge of the sign. - Left turn: left justified on the Type 1 arrow.

Direction arrow.

•

5-33

Control destination.

Version 0.1


One control destination and one intermediate destination where applicable should be displayed on any CHEVRON DIRECTION sign displaying a route number symbol.

One local destination, street name or number, or parking symbol may be displayed if a turning movement does not have a route number or control destination. Signing of local destinations such as these should be coordinated with and approved by the Department.

Vertical placement: - Centered on the sign with the Arabic text above the English text.

Vertical placement: - Centered on the sign with the Arabic text above the English text.

Horizontal placement: - Right turn: Arabic text is right justified on right turn Type 2 arrow and on the right edge of the sign for left turn signs. The English text is left justified on the route number emblem. •

Horizontal placement: - Right turn: Arabic text is right justified on right turn Type 2 arrow and on the right edge of the sign for left turn signs. The English text is left justified on the route number emblem.

Supplemental symbol and destination.

5.6

Same as for route number emblem and control destination (see above). •

City center symbol.

5.6.1 TYPES OF GRADESEPARATED JUNCTION SIGNS

The symbol will only be used with a route that has Abu Dhabi City Center as a control destination.

The following types of guide signs may be specified for use on the free-flowing roadway of a grade-separated junction whether this is on an Emirate Route or an Abu Dhabi Route:

Placement: - To the right of the destination name and centered vertically on the Arabic and English legends. •

• • • • •

Airport symbol. The symbol may be added to the primary sign or used in a separate CHEVRON DIRECTION sign to trailblaze a turn to the Airport. When used as a second CHEVRON mounted on the same post, both CHEVRON DIRECTION signs should be the same size.

•

- To the left of the route number. - Centered in the sign when used separately.

•

Local destination.

Version 0.1

ADVANCE EXIT DIRECTION sign. EXIT DIRECTION sign. ONGOING DIRECTION sign. GORE EXIT sign. SUPPLEMENTAL EXIT sign.

A grade-separated junction may occur between two routes which have one of the following characteristics:

Placement:

•

GRADE-SEPARATED JUNCTION SIGNS

5-34

Both routes have full access control and all elements of the junction are free flowing and grade separated. Such a junction between two such freeways does not give access to the at-grade street network and is termed a “systems” interchange. One route is a freeway with full access control and the other is essentially an at-grade road (although it may have occasional gradeseparated junctions) with only limited access


•

control. Such a junction is termed an “access” interchange allowing connection between the at-grade street network and a freeway, and vice versa. Both routes are essentially at-grade routes with limited access control but have selected grade-separated junctions to improve junction capacity.

- Extra forward ADVANCE EXIT DIRECTION sign 551 for interchanges with other freeways/expressways, at 2,000 meters in advance of the theoretical gore (optional sign, recommended for systems interchanges). Recommended range: 1,800 meters to 2,300 meters. - Forward ADVANCE EXIT DIRECTION sign 551 for all freeway/expressway exits, at 1000 meters in advance of the theoretical gore (mandatory). Recommended range: 900 meters to 1,200 meters. - ADVANCE EXIT DIRECTION sign 551 for all freeway exits 500 meters in advance of the theoretical gore (optional). Recommended range: 400 meters to 600 meters.

The at-grade portion of any of the latter two junction types, including any off-and-on ramps fromand-to the freeway, should be signed using conventional at-grade direction signs as detailed in Section 5.5. However, site-specific roadway geometry may, at times, require the at grade roadway to be signed using the following sign types to indicate lane assignment. Such variations can only be implemented with the prior approval of the Department.

•

All free-flowing roadways approaching a gradeseparated interchange up to and including the exit ramp gore area should be provided with at least one of each of the above sign types with the exception of the SUPPLEMENTAL EXIT sign which is optional.

- ADVANCE EXIT DIRECTION sign 551: (optional but recommended for posted speeds less than 80 km/hour, mandatory for posted speeds of 80 km/hour or higher) At 500 meters in advance of the exit nose. Permissible range: 250 meters to 600 meters, provided that the sign 551 is at least 200 meters from the EXIT DIRECTION sign 552.

5.6.2 ADVANCE EXIT DIRECTION SIGN 551 5.6.2.1 •

•

•

•

FUNCTION

To provide advance indication of destinations served by an exit ramp at the interchange or grade-separated intersection ahead. To indicate the lane or lanes that should be followed to reach the exit ramp.

5.6.2.2

On carriageways of arterial roads, approaching exit ramps to other roads at grade-separated intersections, to provide the following sequence of signs:

•

•

APPLICATION AND LOCATION

Overhead on gantries or cantilever supports in advance of single-lane and multiple-lane exit ramps, each with or without lane drops at an interchange or grade-separated intersection. On carriageways of freeways/expressways in advance of exit ramps connecting with other freeways/expressways (systems interchanges), with arterial roads, or streets (access interchanges) to provide the following sequence of signs:

• •

5-35

Figure 5-7 shows layouts for typical applications of ADVANCE EXIT DIRECTION sign 551. The ADVANCE EXIT DIRECTION sign must extend over the exit lanes. Downward pointing arrows indicate the lanes to be followed. For a single-lane exit, the sign must display the destination information for the route it is leading onto. If the single-lane exit serves both directions of the crossing road the control destination for each direction should be displayed. When each direction has a different route number, the sign should display the route numbers for both directions. If a two-lane exit serves both directions on the crossing road, destination information for both directions should be displayed. When a two-lane exit ramp separates into two roadways for different directions within Version 0.1


Detail 5-7-1 Single Lane Exit: No Lane Drop, Airport Destination

Detail 5-7-2 Single Lane Exit: No Lane Drop, Airport Destination, City Center Destination

Detail 5-7-3 Single Lane Exit: With Lane Drop

Detail 5-7-4 Two Lane Exit: With One Lane Drop, Two Exit Numbers

Detail 5-7-5 Two Lane Exit: With Two Lanes Dropped, One Route Number

Detail 5-7-6 Two Lane Exit: With One Lane Drop, Ramp Split, Two Exit Numbers

Figure 5-7 Advance Direction Sign 551

Version 0.1

5-36


•

•

500 meters after the exit gore, then two separate signs should be used, one for each lane. The left-hand sign must display the destination information for the left-hand branch road. The right-hand sign must display the destination information for the right-hand branch. When a grade-separated junction is provided on an Abu Dhabi Route an ADVANCE EXIT DIRECTION sign 551 should be used following the same basic principles as described above. When a lane on the approaching carriageway ends and becomes the exit ramp (a lane drop), a white panel with the message EXIT should be displayed at the bottom of the sign over the lane or lanes that are dropped.

sign should be displayed on the ADVANCE EXIT DESTINATION sign(s). The layout examples for EXIT DIRECTION signs shown in Figure 5-8 (see Section 5.6.3) correspond to the ADVANCE EXIT DIRECTION signs shown in Figure 5-7. They illustrate the matching of messages on the ADVANCE EXIT DIRECTION signs and EXIT DIRECTION signs. The following items only, are eligible for display on ADVANCE EXIT DIRECTION signs 551: • • • • • • •

In Figure 5-7, Detail 4, the left hand lane has a downward pointing arrow indicating the lane to be used for the exit. However, there is no white lane drop panel indicating EXIT for this lane. The absence of the lane drop EXIT panel means that the lane is a shared lane serving the ongoing destination as well as the exit destinations. The lane in fact forms part of the mainline carriageway.

Downward pointing arrow Type 7. Route number emblem. Control destination/intermediate destination. City center symbol. Airport symbol. Distance to exit. Lane-drop EXIT panel.

The policy on the display of each of these items and their placement on the sign are described below and illustrated in Figure 5-7. •

Downward pointing arrow.

The fact that a two-lane off-ramp is required indicates that a high volume of traffic will be exiting. The shared lane will need to carry a significant proportion of the exit ramp traffic. The capacity of a two-lane exit ramp is dependent on the number of through vehicles that remain in the shared lane. The fewer through vehicles, the higher the capacity of the exit ramp. Strangers who do not know that they can stay in an optional lane to reach ongoing destinations may move out of the shared lane into a lane indicated for ongoing destinations. However, most regular users of the interchange will know that it is not mandatory for them to move out of the shared lane. The regular users will make up the greatest proportion of users.

One downward pointing Type 7 arrow should be displayed for a single lane exit and two Type 7 arrows should be displayed for a twolane exit, as shown in Figure 5-7.

5.6.2.3


If no lane drop occurs at the exit, the arrows should be white. If one or more lanes are dropped at the exit, the arrows indicating the lanes to be dropped should be black (see lane-drop panel). Vertical placement: - The arrows should be placed at the bottom of the sign.


- Each arrow should be placed over the centerline of the lane to which it refers with a tolerance to the left or right of up to 300 millimeters.

All information relating to routes and destinations displayed on a subsequent EXIT DIRECTION sign 552 should be displayed on the preceding ADVANCE EXIT DIRECTION sign(s) 551. No destinations or routes that are additional to those displayed on the EXIT DIRECTION

• 5-37

Route number emblem. Version 0.1


Only the route number emblem of the route or routes accessed directly from the exit ramp should be displayed. One route number only should be displayed if the route reached directly has the same route number on both sides of the interchange. If the route reached directly has different route numbers on each side of the interchange, and both can be reached from the exit ramp, then both route numbers should be displayed.

If the route reached from the exit ramp provides for travel only to the right or only to the left, then only one control or intermediate destination should be displayed for the route. If the road reached from the ramp has different route numbers on either side of the ramp junction, the appropriate control or intermediate destination for each route for the direction of travel available from the exit ramp should be displayed adjacent to the appropriate route number emblem so that the left turn information is placed above the right turn information.

Vertical placement: - Each emblem should be located centrally on the lines of legend for the Arabic and English destination names associated with the route number.

If the use of intermediate destinations presents difficulties, such as the sign becomes too large or the amount of information displayed on the sign exceeds the amount that can be comfortably absorbed by the driver (see 5.2), then, in the interests of public safety, the intermediate destinations should be omitted from the sign.

Horizontal placement: - For single-lane exit ramps, the route number emblem(s) should be placed at the left of the sign. For two-lane exit ramps, the emblems should be placed adjacent to the destination names on their left side. The combined emblem and destination name message should be centered between the borders. If more than two destinations are necessary, it may be more effective to place the route number emblem centrally with Arabic text to the right, and English text to the left. •

Vertical placement: - The Arabic legends should always be displayed above the English legends. When two destinations are related to one route number, the Arabic right-turn destination name should be immediately below the Arabic left turn destination name. The two English legends should be similarly displayed, one immediately below the other, and both below the Arabic legends. - When two route numbers with one destination each are displayed, the route number emblem and associated destination legend for the destination to the left at the exit ramp, should be above the route number emblem and legend for the destination to the right at the exit ramp.

Control destination. A maximum of one control destination and one intermediate destination, where applicable, is permitted for each direction (left or right) on ADVANCE EXIT DIRECTION sign 551. The upper destination name should be the control or intermediate destination for the route reached directly from the off-ramp in the direction to the left of the off ramp. The lower destination name should be the control or intermediate destination for the route reached directly from the off ramp in the direction to the right of the off ramp. The signs displayed to drivers travelling on the opposite approach to the interchange will have the vertical order of the specific destination names reversed.)

Version 0.1

Horizontal placement: The control destination and intermediate destination, where applicable, should be displayed adjacent and to the right of the associated route number emblem, as shown in Figure 5-7.

5-38


- English legend should be left justified and adjacent to the right edge of the route number emblem. - Arabic legend should be right justified. The position of the right justification line should be the furthest right of the following:

the location falls outside the recommended range, the actual distance to the nearest 100 meters should be displayed. For distances less than 400 meters the actual distance may be rounded to the nearest 50 meters. When two or more successive exits occur at an interchange, the signs should indicate the different distances. If the advance sign is located within the recommended range, the nominal distance should be used for the first exit. The second and subsequent exits should indicate a distance equal to the nominal distance used for the first exit plus the distances from the first exit to the subsequent exits. All distances should be rounded up to the next 100 meters.

• The longest English word. • The longest Arabic word, with its left end adjacent to the route number emblem. When two route numbers are used, the same right justification for the Arabic destinations should be used for both route numbers. •

Airport symbol.

Vertical placement:

The airport symbol may be displayed if the route served by the ramp has the airport as a trailblaze destination.

- Centered approximately on the downward pointing arrow(s). Horizontal placement:

When used the symbol should be located to the left of the route number emblem.

- On the left side of the sign to the left of the furthest left downward pointing arrow.

The aircraft symbol should be oriented in the direction in which traffic must travel to reach the airport. For the ongoing direction the aircraft symbol must “point” upwards. •

•

If a lane on a mainline carriageway will be dropped at an exit ramp, a white EXIT panel should be displayed.

City center symbol. Vertical placement: -

The Arabic and English word EXIT should be displayed adjacent to and to the right of a single arrow, with the Arabic above the English, both centered approximately vertically in the panel. When two lanes are dropped at the exit, the EXIT panel extends for the full width of the sign. In such a case the word EXIT in Arabic and English may be displayed centrally between the two downward pointing arrows.

Centered in each stack.

Horizontal placement: •

White lane-drop EXIT panel.

Right justified in each stack.

Distance to exit. The distance to the exit should be displayed in English and Arabic numerals as shown in Figure 5-7. When the ADVANCE EXIT DIRECTION sign has been located within the permissible ranges of distances from the exit, specified under “Application,” above, the nominal distances 500 meters, 1,000 meters, 2,000 meters should be displayed. If

The panel is placed at the bottom of the sign and covers the space occupied by the relevant downward pointing arrow(s), which should be black. The white panel extends over the lane or lanes to be dropped, from the edge of the sign to a point above the lane line remote from the edge of the sign. White sign borders 5-39

Version 0.1


•

adjacent to the panel should be incorporated into the panel.

5.6.3 EXIT DIRECTION SIGN 552 5.6.3.1 • • •

To indicate the location of the exit ramp at an interchange or grade-separated intersection. To indicate by an arrow configuration the direction of the exit. To repeat the destination information that has been shown on the preceding advance exit direction signs 551 and thereby reassure the driver of the destination(s) served.

5.6.3.2 • •

• •

•

• •

•

FUNCTION

5.6.3.3 •

APPLICATION

•

At single-lane and multiple-lane exit ramps, each with or without lane drops, at interchanges or grade-separated intersections. On carriageways of freeways, at exit ramps, connecting with other freeways (systems interchanges) or with arterial roads or streets (access interchanges). On carriageways of grade-separated arterial roads at exit ramps to other roads. Figure 5-8 shows layouts for typical applications of EXIT DIRECTION signs 552. The EXIT DIRECTION sign must extend over the exit lanes. Upward pointing arrows should be slanted (normally to the right) to emphasize the change of alignment. For a single-lane exit, the sign must display the destination information for the route it is leading onto. If the single-lane exit serves both directions of the intersecting crossroad, and each direction has a different route number, the sign should display the route number emblems for both directions. If a two-lane exit serves both directions on the intersecting crossroad, destination information for both directions should be displayed. When a two-lane exit ramp separates into two roadways for different directions within 500 meters after the exit gore, then two separate signs should be used, one for each lane. The left-hand sign must display the destination information for the left-hand branch road. The right-hand sign must display the destination information for the right-hand branch.

Version 0.1

When a grade-separated junction is provided on an Abu Dhabi Route an EXIT DIRECTION sign 552 should follow the same basic principles as described above. When a lane on the approaching carriageway ends and becomes the exit ramp (a lane drop), a white panel with the message EXIT should be displayed at the bottom of the sign over the lane or lanes that are dropped. LOCATION

At the theoretical gore, up to 50 meters after the theoretical gore, or up to 100 meters in advance of the theoretical gore provided that the exit lane or lanes have been developed to full lane width. The sign should be mounted overhead the exit lane or lanes, on gantries or cantilever supports.

5.6.3.4


All information relating to routes and destinations displayed on the preceding ADVANCE EXIT DIRECTION signs 551 should be displayed on the subsequent EXIT DIRECTION signs 552. No destinations or routes that are additional to those displayed on the ADVANCE EXIT DIRECTION signs should be displayed on the EXIT DIRECTION signs. The layout examples for EXIT DIRECTION signs shown in Figure 5-8 correspond to the ADVANCE EXIT DIRECTION signs shown in Figure 5-7. They illustrate the matching of messages on the ADVANCE EXIT DIRECTION signs and EXIT DIRECTION signs. Only the following items are eligible for display on EXIT DIRECTION signs 552: • • • • • •

5-40

Upward pointing arrow Type 8 (inclined in the direction of the exit ramp). Route number emblem. Control destination/intermediate destination. City center symbol. Airport symbol. Lane drop EXIT panel.


Detail 5-8-1 Single Lane Exit: No Lane Drop, Airport Destination

Detail 5-8-2 Single Lane Exit: No Lane Drop, Airport Destination, City Center Destination

Detail 5-8-3 Single Lane Exit: With Lane Drop

Detail 5-8-4 Two Lane Exit: With One Lane Drop, Two Exit Numbers

Detail 5-8-5 Two Lane Exit: With Two Lanes Dropped, One Route Number

Detail 5-8-6 Two Lane Exit: With One Lane Drop, Ramp Split, Two Exit Numbers

Figure 5-8 Exit Direction Sign 552

5-41

Version 0.1


The policy on the display of each of these items and their placement on the sign is described below and illustrated in Figure 5-8. •

Vertical placement: - Each emblem should be located centrally on the lines of legend for the Arabic and English destination names associated with the route number.

Upward pointing arrow. One upward pointing arrow Type 8 should be displayed for a single lane exit, and two Type 8 arrows should be displayed for a two-lane exit, as shown in Figure 5-8. The arrows should be slanted to represent the direction of the exit ramp (normally at 45° to the right of vertical).

Horizontal placement: - For single-lane exit ramps, the route number emblem(s) should be placed at the left side of the sign, as shown in Figure 5-8. For two-lane exit ramps, the emblems should be placed adjacent to the destination names on their left side. The combined emblem and destination name message should be centered between the borders. If more than two destinations are necessary, it may be more effective to place the route number emblem centrally with Arabic text to the right and English text to the left.

If no lane drop occurs at the exit, the arrows should be white. The number of lanes at the exit is determined by the mainline lanes from which it is possible to directly exit the mainline, not the number of lanes on the off ramp that develop after the theoretical gore. •

If one or more lanes are dropped at the exit, the arrows indicating the lanes to be dropped should be black.

A maximum of one control destination and one intermediate destination, where applicable, is permitted for each cardinal direction on EXIT DIRECTION sign 552. The upper destination name should be the control or intermediate destination for the route reached directly from the off ramp in the direction to the left of the off ramp. The lower destination name should be the control/intermediate destination for the route reached directly from the off ramp in the direction to the right of the off ramp.

Vertical placement: - The arrows should be placed at the bottom of the sign. Horizontal placement: - Each arrow should be placed over the centerline of the lane to which it refers with a tolerance to the left or right of up to 300 millimeters. •

If the route reached from the exit ramp provides for travel only to the right or only to the left, then only one control or intermediate destination should be displayed for the route.

Route number emblem. Only the route number emblem of the route or routes accessed directly from the exit ramp should be displayed. One route number only should be displayed if the route reached directly has the same route number on both sides of the interchange. If the route reached directly has different route numbers on each side of the interchange, and both can be reached from the exit ramp, then both route numbers should be displayed.

Version 0.1

Control destination

If the road reached from the ramp has different route numbers on either side of the ramp junction, the appropriate control or intermediate destination for each route for the direction of travel available from the exit ramp should be displayed adjacent to the appropriate route number emblem so that the left turn information is placed above the right turn information.

5-42


If the use of intermediate destinations presents difficulties, such as the sign becomes too large, or the amount of information displayed on the sign exceeds the amount that can be comfortably absorbed by the driver (see Section 5.2), then, in the interests of public safety, the intermediate destinations should be omitted.

tinations should be used for both route numbers. •

Airport symbol. The airport symbol may be displayed if the route served by the ramp has the airport as a trailblaze destination. When used the symbol should be located to the left of the route number emblem.

Vertical placement: - Where Arabic legends and English legends are stacked vertically, the Arabic legends should always be displayed above the English legends.

The aircraft symbol should be oriented in the direction in which traffic must travel to reach the airport. When the arrow(s) on EXIT DIRECTION signs are slanted at 45° towards the exit ramp, the aircraft should be slanted at 45° in the same direction, diagonally in its white background panel.

- When two destinations are related to one route number, the Arabic right turn destination name should be immediately below the Arabic left turn destination name. The two English legends should be similarly displayed, one immediately below the other, and both below the Arabic legends. - When two route numbers with one destination each are displayed, the route number emblem and associated destination legends for the destination to the left at the exit ramp should be above the route number emblem and legend for the destination to the right at the exit ramp.

•

City center symbol. Vertical placement: -

Centered in each stack.

Horizontal placement: •

Right justified in each stack.

Lane-drop EXIT panel.

Horizontal placement: If a lane on a mainline carriageway will be dropped at an exit ramp, a white EXIT panel should be displayed.

- The control destination and intermediate destination, where applicable, should be displayed adjacent to the associated route number emblem, to the right of it, as shown in Figure 5-8. - English legend should be left justified and adjacent to the right edge of the route number emblem. - Arabic legend should be right justified. The position of the right justification line should be the furthest right of the following:

The panel is placed at the bottom of the sign and covers the space occupied by the relevant upward pointing arrow(s), which should be black. The white panel extends over the lane or lanes to be dropped, from the edge of the sign to a point above the lane line remote from the edge of the sign. White sign borders adjacent to the panel should be incorporated into the panel.

• The longest English word. • The longest Arabic word, with its left end adjacent to the route number emblem.

The English and Arabic word EXIT should be displayed adjacent to and on the right side of a single arrow, with the Arabic above the English both approximately centered vertically on the panel. When two lanes are dropped at the exit the EXIT panel extends

- When two route numbers are used, the same right justification for the Arabic des5-43

Version 0.1


for the full width of the sign. In such a case the word EXIT in Arabic and English may be displayed centrally between the two upward pointing arrows.

5.6.4 ONGOING DIRECTION SIGN 553 5.6.4.1

FUNCTION

•

To provide information about the control destination that will ultimately be reached by remaining on the mainline carriageway, using the through lanes at a point where there is an exit from the mainline carriageway at an interchange or gradeseparated intersection. 5.6.4.2 •

•

• •

•

5.6.4.4

The following items are eligible for display: • • • •

Downward pointing arrow type 7. Route number emblem. Control destination/intermediate destination. Airport symbol.

The description of these items and their positions on the sign are given below and illustrated in Figure 5-9.

LOCATION

•

Overhead on gantries. When only one ONGOING DIRECTION sign 553 is applied, the preferred location is adjacent to the ADVANCE EXIT DIRECTION sign 551, when used, at 500 meters from the theoretical gore. The next and most common, most effective location is adjacent to the Forward ADVANCE EXIT DIRECTION sign 551 at 1000 meters from the theoretical gore. For more complicated or high volume interchanges, at least two ONGOING DIRECTION signs 553 should be used. One of these should be at the theoretical gore, adjacent to the EXIT DIRECTION sign 552. This is needed to ensure that drivers can make a final decision about continuing straight on, or exiting. The other sign should be applied adja-

Version 0.1


The sign should be positioned over the ongoing lanes and be of sufficient width to display downward pointing arrows over the centers of all ongoing lanes except optional exit lanes.

APPLICATION

Used on mainline carriageways in conjunction with overhead ADVANCE EXIT DIRECTION signs 551 and overhead EXIT DIRECTION signs 552, at interchanges and grade-separated intersections. At simple interchanges it is mandatory to have at least one ONGOING DIRECTION sign 553. For complicated interchanges, where a high volume of lane changing will be necessary, at least two ONGOING DIRECTION signs 553 should be applied.

5.6.4.3

cent to the forward ADVANCE EXIT DIRECTION sign 551, at 1000 meters ahead of the theoretical gore. If the available distance ahead of the exit is too short to place a sign at 1,000 meters in advance, the ONGOING DIRECTION sign 553 should be placed adjacent to the ADVANCE EXIT DIRECTION sign 551 at 500 meters or more in advance of the exit. For interchanges on arterial routes at least one ONGOING DIRECTION sign 553 should be applied. The preferred location is adjacent to the ADVANCE EXIT DIRECTION sign 551.

Downward pointing arrow. One downward pointing arrow Type 7 should be displayed over the center of each lane available for through traffic, and which is not designated as a shared lane for exiting traffic (the shared lanes will have an ADVANCE EXIT DIRECTION sign 551 or an EXIT DIRECTION sign 552 over them). Placement: - The arrows should be located at the bottom of the sign, as shown in Figure 5-9. Horizontally, the arrows should be located over the center of the lanes concerned, with a tolerance to the left or right of up to 300 millimeters.

5-44


Forward Advance Exit Direction Sign 551, OR Advance Exit Direction Sign 551, OR Exit Direction Sign 552

Detail 5-9-1: Three Ongoing Lanes: Airport Trailblazer Indicated


Detail 5-9-2: Two Ongoing Lanes


Detail 5-9-3: Three Ongoing Lanes

Figure 5-9 Ongoing Direction Sign 553

5-45

Version 0.1


•

Route number emblem.

Additional intermediate destinations may at times be required. Such additions may only be implemented with the prior approval of the Department.

Only the route number emblem of the ongoing route should be displayed. Vertical placement:

A trailblazing airport symbol may also be displayed on sign 553.

- The route number emblem should be located centrally to the lines of legend for the Arabic and English destination name associated with the route number, as shown on Figure 5-9.

Vertical placement: - The Arabic legend should be displayed above the English legend. - Where multiple destinations are used, the Arabic legend should be displayed in a stack on the right hand side of the sign, and the English legend should be displayed in a stack on the left hand side of the sign.

Horizontal placement: - The route number emblem should appear on the left side of the control destination legend, and adjacent to it. The combined message, consisting of the route number emblem and the control destination should be centered on the sign, as shown in Figure 5-9. When intermediate destinations are used in addition to the control destination, it is a more effective use of the available sign area to place the route number emblem centrally with Arabic text to the right and English text to the left as indicated in Figure 5-9. •

Horizontal placement: - The control destination should be displayed adjacent to the associated route number emblem and to the right of it. - English legend should be left justified and adjacent to the right edge of the route number emblem. - Arabic legend should be right justified on the right end of the English legend unless the Arabic legend is longer in which case it should be left justified on the route number emblem. - Where multiple destinations are used, the Arabic legend should be displayed in a stack right justified, to the right of the centrally located route number emblem. The English legend should be displayed in a stack, left justified, to the left of the centrally located route number emblem.

Control destination. The only destination name eligible for display is the control destination and one intermediate destination, where applicable, designated for the route, in the direction applying to the subject carriageway. The control destinations for all routes are specified in Section 5.1.4 (see Table 5-1). Where an intermediate control destination has been designated, it should be displayed on signs 553 from the beginning of the route, until that destination has been reached. From that point on, the next appropriate intermediate destination for the route should be displayed along with the control destination.

The combined message, consisting of airport symbol (if eligible for the route), route number emblem, and control destination should be centralized on the sign, as shown in Figure 5-9. •

In the case of some Emirate Routes, the intermediate destination is Abu Dhabi. That destination should be used until the boundary of the municipal area of Abu Dhabi is reached.

Version 0.1

Airport symbol. The airport symbol should be displayed only if the route has the airport as a control destination, or if it is designated for trailblazing in Section 5.4.2.

5-46


• •

The symbol should be placed to the left of the route number emblem, and vertically centered on it.

The items eligible for display, and their positions on the signs are described below and illustrated in Figure 5-10.

The aircraft symbol should be oriented in the direction in which traffic must travel to reach the airport. For the ongoing direction the aircraft must “point” upward.

•

5.6.5 GORE EXIT SIGNS 554 AND 556 5.6.5.1 • •

• • • •

FUNCTION

For gores where a ramp splits into two branches, two upward pointing Type 8 arrows should be used on GORE EXIT sign 556. They should be inclined at 45° to the left and right of vertical, as shown in Figure 5-10, Detail 2.

APPLICATION AND LOCATION

At the exit ramps from freeways and arterial roads at interchanges and grade-separated intersections. Where ramps diverge to form two branches. Figure 5-10, Detail 1 shows the application at the exit ramp from an Emirate Route. Figure 5-10, Detail 2 shows the sign where an exit ramp from an Emirate Route splits into two branches.

5.6.5.3

Upward pointing arrow or arrows. For exit ramps from the mainline carriageways of Emirate Routes and Abu Dhabi Routes, one Type 8 arrow should be displayed on GORE EXIT sign 554. It should be slanted upwards at an angle of 45° to indicate the direction of the exit ramp as shown in Figure 5-10, Detail 1.

To indicate the physical nose of the exit ramp from the main roadway. To indicate the physical nose of a split in a ramp.

5.6.5.2

Upward pointing arrow Type 8. EXIT message.

•

EXIT message. The English word EXIT with its Arabic translation above should be centered at the top of the sign.


The following items are eligible for display:

SIGN 554

SIGN 556

Detail 5-10-1 Gore Exit Sign for Emirate Route

Detail 5-10-2 Gore Exit Sign for Two Branch Exit Ramp

Figure 5-10 Gore Exit Signs 554 and 556

5-47

Version 0.1


5.6.6 SUPPLEMENTAL EXIT SIGN 557

5.6.6.4


The following items are eligible for display: 5.6.6.1

FUNCTION

• • •

To provide exit information for supplemental destinations (commonly for tourists) not eligible for inclusion on the main direction signs. 5.6.6.2

The information eligible for display and its position on the sign is described below and illustrated in Figure 5-11.

APPLICATION

For exits from freeways or expressways at interchanges or grade-separated intersections. 5.6.6.3 •

•

•

Upward pointing arrow Type 8. Approved supplemental sign symbol. Approved supplemental destination (“Primary” or identifying name only).

•

Upward pointing arrow.

LOCATION The upward pointing Type 8 arrow should be displayed on the right side of the sign for a right hand exit ramp. The arrow should be pointing upward, slanted at an angle of 45o to the right of vertical. It should be centered vertically on the sign.

Normally ground mounted as a stack type sign on the right hand side. May be erected overhead on a cantilever if necessary due to space restrictions or visibility restrictions. At the beginning of the taper for the deceleration lane, or in the case of a lane drop 200 meters to 250 meters in advance of the theoretical gore. On freeways the sign should be at least 200 meters after the ADVANCE EXIT DIRECTION sign 551 that is located 500 meters in advance of the theoretical gore.

•

Approved supplemental symbol and destination. A maximum of two supplemental destinations should be displayed on any SUPPLEMENTAL EXIT sign 557. More destinations will significantly increase driver workload by providing too much visual information to read and comprehend in the short time available before exiting onto the exit ramp.

If the sign is mounted overhead on a cantilever it should be at least 250 meters in advance of the EXIT DIRECTION sign 552. The location should be thoroughly checked to prevent an overhead SUPPLEMENTAL EXIT sign 557 from obscuring the visibility of the EXIT DIRECTION sign 552. This checking should include plotting the sign on a plan of the horizontal alignment and on a longitudinal section of the vertical alignment.

Only approved symbols illustrated in Figure 5-5 and approved destinations designated in Section 5.1.5 are eligible for display. If more than two destinations are eligible for display, the Department should decide which two are most important, and only those two should be displayed.

Figure 5-11 Supplemental Exit Sign 557

Version 0.1

5-48


Placement: The destinations are displayed as shown in Figure 5-11. The symbol should be displayed on the left side of the sign, with the Arabic and English destination names adjacent to it on the right side. For each destination: - English legend should be left justified and adjacent to the right edge of the associated symbol. - Arabic legend should be right justified. The position of the right justification line should be the furthest right of the following:

Sign 585

5.7.1.3

• The longest English word. • The longest Arabic word, with its left end adjacent to the associated symbol.

•

When two supplemental destinations are displayed, the destination to the left of the exit ramp should be above the destination to the right. If both are in the same direction the closer destination should be at the top.

5.7

•

•

GENERAL INFORMATION SIGNS

•

The signs classified in this group provide additional information to drivers to assist them with their navigational task or to provide supplementary information with respect to regulatory or warning signs. Neither of the signs in this group should include an arrow or other directional message.

5.7.1 5.7.1.1

LOCATION

On the carriageways leading away from Abu Dhabi, 500 meters beyond the city boundary and approximately every 20 kilometers thereafter. On the carriageways leading to Abu Dhabi, 500 meters before the city boundary and approximately every 20 kilometers preceding. Ground mounted on the right-hand side of the carriageway. A minimum of 500 meters from any other guide sign, preferably near the midpoint between interchange junctions.

5.7.1.4


DISTANCE sign 585 may display up to a maximum of three cities or towns. The names of the cities and the distances to them should be displayed in Arabic and in English. The Arabic names of the cities or towns should be displayed at the top of the sign and the English names at the bottom of the sign.

DISTANCE SIGN 585 FUNCTION

To inform drivers, entering or leaving a city or town, of significant destinations and the corresponding travel distances to them.

The top line of each language group should identify the next significant destination along the route and show the distance to it.

5.7.1.2

The bottom line in a language group should indicate the name of a control city that has national significance for travelers using the route. This may also be interpreted as a significant city defining the end of the route.

APPLICATION

To be used on Emirate Routes only.

5-49

Version 0.1


If there is a city of commercial or tourist importance between these two destinations, its name may be displayed on the middle line of a language group. The only exception to the above guidelines and parameters is when DISTANCE sign 585 is used on route number E11. Being the primary route that connects Abu Dhabi with Dubai and the other Northern and Eastern Emirates, it is therefore permissible to show all the necessary Emirates.

Sign 586

Distances to destinations in Arabic should be located on the left of the sign, and should be right justified. Distances should be displayed in kilometers (integers). Arabic destinations should be right justified, based on the longest Arabic or English word being positioned a controlling space to the right of the longest distance displayed.

5.7.2.2

English destinations should be left justified, on the left of the sign.

The sign should be located in a side-mounted position on both sides of the roadway, up to 160 meters from the junction, with due regard to the position of any other direction signs and any minor side road intersections.

APPLICATION

HIGH VEHICLE EXIT sign 586 may be used on Emirate Routes or any other appropriate local street. 5.7.2.3

Distances in English should be displayed on the right side, right justified. A controlling distance should be provided between the longest English or Arabic word and the longest distance displayed.

LOCATION

5.7.3 TEXT SIGN 588

The sign width will be dictated by the longest English word plus longest distance or the longest Arabic word plus longest distance.

5.7.3.1 •

To identify for drivers the boundary of a suburb/community or to identify the name of a bridge, tunnel, or other physical feature.

•

To convey a textual message of regulation, warning, or information that cannot otherwise be conveyed with conventional signs or with a SUPPLEMENTARY PLATE sign 589.

The color of this sign should be blue background with white legend. In cases where DISTANCE sign 585 and ROUTE MARKER sign 501 appear in approximately the same location, consideration may be given to displaying both signs together.

FUNCTION

5.7.3.2

APPLICATION.

5.7.2 HIGH VEHICLE EXIT SIGN 586 5.7.2.1

TEXT sign 588 may be used on Emirate Routes or any other appropriate local street.

FUNCTION

To inform drivers of high vehicles that they are required to exit the roadway at the next turn off.

Sign 588

Version 0.1

5-50


5.7.3.3 •

• •

LOCATION

works traffic sign without materially altering the meaning of the sign it supplements.

Ground mounted on the right side of the roadway at the boundary of the suburb or community or within 50 meters of such boundary, within the suburb. At a point within the vicinity of the feature being identified whereby the feature identified is obvious. As per applicable requirements for locating regulatory, warning, or guide signs.

5.7.3.4

5.7.4.2

To be used as appropriate with regulatory, warning, or roadworks traffic signs as variously described in Chapters 3, 4, and 7 respectively. 5.7.4.3

LOCATION

Always directly below the primary sign that it is supplementing. It may take the form of a separate sign plate affixed separately, but to the same post as the primary sign, or it may be incorporated into an enlargement of the primary sign substrate material.


Information eligible for display on TEXT sign 588 is a limited text message in Arabic and English. The legend should be displayed with the Arabic legend above the English legend. The sign should be sized from the longer text component. When this is the Arabic legend, the English legend should be left justified on the end of the Arabic name. When the English legend is the longer component, the Arabic legend should be right justified on the end of the English legend.

5.7.4.4


SUPPLEMENTARY PLATE sign 589 displays, in Arabic over English, only information which falls into one of the following categories: •

This sign has a white background with a black border and legend. When used for roadworks, the background color is yellow.

•

5.7.4 SUPPLEMENTARY PLATE SIGN 589

•

5.7.4.1

APPLICATION

•

FUNCTION

To provide information which supplements the message given on a regulatory, warning, or road-

•

A text message comprised of one or two words only, such as “School.” An advisory speed at which the hazard forewarned by the primary sign can be negotiated, such as “50km/h” on a roadway which otherwise has a higher speed limit. The distance from the location of the sign to the point where the condition it describes exists, such as “200 m.” The distance, beginning at the location of the sign, over which the message of the sign applies, such as “For 3 km.” An easily recognized iconic symbol, such as that used to depict “no trucks.”

Sign 589

5-51

Version 0.1


The SUPPLEMENTARY PLATE sign should be the same width as the primary sign which it supplements. A SUPPLEMENTARY PLATE sign should always have a black border and legend. It should have a white background when used with Regulatory or Warning signs, and a yellow background when used with Roadworks signs.

5.7.5 FIRE HYDRANT SUPPLEMENTARY PLATE SIGN 590 5.7.5.1

FUNCTION

To provide information on the location and identification number of a fire hydrant. 5.7.5.2

APPLICATION

To be used with NO STOPPING sign 370 to prevent vehicles from stopping on roads or other curbside areas adjacent to fire hydrants. Details of signing and pavement marking for areas near fire hydrants are described in Chapter 8. 5.7.5.3

F. H. W. 14/1 NO. . . Figure 5-12 Sign 590 with No Stopping Sign 370

LOCATION

Note that this sign combination is to be mounted on a red pole.

Mounted below NO STOPPING sign 370, as shown in Figure 5-12. 5.7.5.4

5.7.6 GENERAL SERVICE SIGN 591


5.7.6.1

Sign 590 displays the following information, by line:

To inform motorists of the availability of upcoming services.

1. “Fire Hydrant” in Arabic. 2. The zone, sector number, and hydrant number in Arabic. 3. The letters “F. H.” for fire hydrant followed by the zone, sector number, and hydrant number in English.

5.7.6.2

APPLICATION

GENERAL SERVICE sign 591 informs motorists of services available either adjacent to the roadway or at a nearby, upcoming exit from the roadway. Only services that fulfill the needs of the road user should be shown on general service signs.

As Abu Dhabi Civil Defence is responsible for assigning numbers to fire hydrants, these signs should be prepared in coordination with that agency.

Services eligible for this sign include: • • • • •

Sign 590 should have a red background with a white legend.

Version 0.1

FUNCTION

5-52

Petrol station. Mechanic. Restaurant. Hotel. Refreshments.


NEXT EXIT Sign 591 (typical)

• • • • •

Public telephone. Hospital (with a physician on duty 24 hours a day). First aid station (open 24 hours a day). Major shopping center. Mosque.

5.7.6.3

AL SERVICE sign 591 should be erected at an appropriate interval. GENERAL SERVICE sign 591 should have a blue background and a white border. Within the blue background, iconic symbols representing specific services should be black (except for the first aid station symbol, which is a red crescent) on a white background as shown in Figure 5-13.

LOCATION

On the approach to the exit to general services, a GENERAL SERVICE sign 591 should be placed 2 kilometers and/or 4 kilometers in advance of the exit. An additional sign should be placed within one-half kilometer of the exit.

As a general rule, the iconic symbols shown in Figure 5-13 should be used only on General Service Sign 591. However, it is permissible to use a single icon as shown in Figure 5-13 on a typical guide sign if the engineer deems it would prove useful to drivers.

General service signing should only be provided at locations where the road user can return to the roadway and continue in the same direction of travel. GENERAL SERVICE sign 591 is generally not appropriate at major interchanges and in urban areas. 5.7.6.4

A supplemental plate should indicate the distance to the exit. Within one-half kilometer of the exit, the supplemental plate should not indicate a distance but have an action message such as NEXT RIGHT or SECOND RIGHT. If, from the last sign indicating general services before the exit, the distance to the next point where services are available is greater than 16 kilometers, an additional supplemental plate, NEXT SERVICES XX KM, may be added to the sign.


Icons should be placed in rows of three across the sign. No more than six services should be signed on an individual sign. If more than six services are available at an upcoming exit, two GENER-

5-53

Version 0.1


Figure 5-13 General Services Iconic Symbols

5.8

with due regard to the position of any other direction signs and any minor side road intersections.

MUNICIPALITY PARKING STRUCTURE SIGNS

MUNICIPALITY PARKING STRUCTURE TRAILBLAZER sign 595 should include the parking structure number on its face.

Municipality parking structures have custom guide signs unique to those structures. Municipality parking structure signs are to be used at all municipality parking structures but should not be used for other parking applications.

The face of sign 595 is identical to that of sign 596. However, sign 595 is supplemented with a ONE WAY sign 306 mounted on the pole below it, pointing the direction of the car park entrance. Furthermore, sign 595 is an aluminum sign panel and is not internally illuminated, as is sign 596.

5.8.1 MUNICIPALITY PARKING STRUCTURE TRAILBLAZER SIGN 595 A MUNICIPALITY PARKING STRUCTURE TRAILBLAZER sign 595 should be used as a trailblazer sign indicating a direction to be taken in order to enter an Abu Dhabi Municipality parking structure.

5.8.2 MUNICIPALITY PARKING STRUCTURE ENTRANCE BANNER SIGN 596 A MUNICIPALITY PARKING STRUCTURE ENTRANCE BANNER sign 596 should be located on the outside and above the vehicular-access opening to the parking structure. MUNICIPALITY PARKING STRUCTURE ENTRANCE

The signs should be located in a side-mounted position on the right side of the main roadway at the entrance of the road or ramp leading to the parking structure. Sign placement should be done

Version 0.1

5-54


Sign 595 and Sign 596

•

BANNER sign 596 should be centered over the opening or adjacent openings. Openings to parking structures may be entrance only, exit only, or a combination of entrance and exit. MUNICIPALITY PARKING STRUCTURE ENTRANCE BANNER sign 596 is used uniformly in all three of these configurations.

•

MUNICIPALITY PARKING STRUCTURE ENTRANCE BANNER sign 596 should be internally illuminated for night-time visibility and should include the parking structure number on its face.

•

5.8.3 MUNICIPALITY PARKING STRUCTURE ENTRANCE SIGN 597 A MUNICIPALITY PARKING STRUCTURE ENTRANCE sign 597 should be located outside and above the opening allowing entry to the parking structure. MUNICIPALITY PARKING STRUCTURE ENTRANCE sign 597 should be located as follows:

If the opening accommodates only one entrance lane, the sign should be centered above the entrance lane, below MUNICIPALITY PARKING STRUCTURE ENTRANCE BANNER sign 596. If the opening accommodates two entrance lanes, one MUNICIPALITY PARKING STRUCTURE ENTRANCE sign 597 should be centered between and above the two lanes and below MUNICIPALITY PARKING STRUCTURE ENTRANCE BANNER sign 596. If the opening accommodates three or more entrance lanes, one MUNICIPALITY PARKING STRUCTURE ENTRANCE sign 597 should be centered above each entrance lane and below MUNICIPALITY PARKING STRUCTURE ENTRANCE BANNER sign 596.

The preceding guidance is applicable whether the opening to the parking structure provides for entrance and exit or for entrance only. Sign 597 should be internally illuminated for night-time visibility.

5.8.4 MUNICIPALITY PARKING STRUCTURE EXIT SIGN 598 A MUNICIPALITY PARKING STRUCTURE EXIT sign 598 should be located outside and above the opening allowing exit from the parking structure. MUNICIPALITY PARKING STRUC-

Sign 597

5-55

Version 0.1


the same way that it would be on the exterior, except that it is mounted on the interior wall.

5.9

PEDESTRIAN UNDERPASS Sign 599 guides pedestrians to the locations of entrances to pedestrian underpasses. Sign 599 should be located within 5 meters of the entrance to a pedestrian underpass and in a position to maximize its visibility for pedestrians from all angles. If one end of a pedestrian underpass has more than a single point of entrance, and those points are located more than 15 meters apart, a separate sign 599 may be installed for each point of entrance. In this case, the signs should be located as close as possible to the point of entrance.

Sign 598

TURE EXIT sign 598 should be located as follows: • •

•

If the opening accommodates only one exit lane, the sign should be centered above the lane. If the opening accommodates two exit lanes, one MUNICIPALITY PARKING STRUCTURE EXIT sign 598 should be centered between and above the two lanes. If the opening accommodates three or more exit lanes, one MUNICIPALITY PARKING STRUCTURE EXIT sign 598 should be centered above each lane.

The sign should be pole-mounted. It has a blue background with a white border and legend.

Where an exit lane(s) is colocated with an entrance lane(s) at a single opening, MUNICIPALITY PARKING STRUCTURE EXIT sign 598 should be positioned below MUNICIPALITY PARKING STRUCTURE ENTRANCE BANNER sign 596 at the same level as the entrance lane’s MUNICIPALITY PARKING STRUCTURE ENTRANCE sign 597. Sign 598 should be internally illuminated for night-time visibility. MUNICIPALITY PARKING STRUCTURE EXIT sign 598 is also used above exit doors on the interior of parking structures. In this application, sign 598 should be located and positioned in

Sign 599

Version 0.1

PEDESTRIAN UNDERPASS SIGN 599

5-56


6

PAVEMENT MARKINGS

6.1

GENERAL

Guidance pavement markings help motorists to understand the path that the roadway designer intends for their vehicle to follow. An example of such is a guide line that may be used to mark out the travel path through an intersection for vehicular turns that are unusual and otherwise difficult to understand.

Pavement markings are defined as markings or other devices applied to, embedded in, or attached to a pavement surface. Pavement markings must function day and night as well as under adverse weather conditions. While pavement markings are an important and integral element in the design of a traffic control scheme, care should be taken not to overuse pavement markings. Due to their nature and location, pavement markings are subject to continual and rapid deterioration and wear from roadway traffic. To retain the conspicuousness and function of pavement markings, their maintenance and replacement is, by necessity, an ongoing and continual process with significant cost implications. Thus, pavement marking requirements should be considered early in the planning and design of a project.

It is important for designers to understand the functional significance of the pavement markings so that their application will be consistent for the use intended. The use of various classes and types of marking in combination with each other and other traffic control devices is illustrated collectively in the figures in Chapter 8.

6.1.2 MARKING TYPES Pavement markings can further be classified into three basic types: • • •

6.1.1 FUNCTION

Transverse lines and markings are those that are placed at right angles or are significantly nonparallel to the longitudinal axis of the roadway. In general, the purpose of a transverse marking is to provide a sense of limit across the normal, unimpeded forward movement of a vehicle. A giveway line is an example of a transverse pavement marking. The give-way line crosses the forward path of a vehicle to advise a driver to stop or be prepared to stop his forward progress in case the situation dictates such action. Because transverse lines must be viewed obliquely from an approaching vehicle, their widths must be substantial to facilitate their detection.

Like traffic signs, pavement markings may be classified with respect to the primary function that they serve: • • •

Transverse lines. Longitudinal lines. Symbols.

Regulatory. Warning. Guidance.

Regulatory pavement markings advise motorists of actions they should or should not take. Disregard for a regulatory pavement marking represents an offense. For example, crossing of a solid no-passing line is illegal and offending drivers would be subject to citation.

Longitudinal lines run generally parallel to the longitudinal axis of the line of vehicular travel on a roadway. In general, the purpose of a longitudinal line is to convey a continual message to the driver of a moving vehicle over an extended length of roadway. A lane line is an example of a longitudinal line. It provides a continual message to a driver demarcating the separation of two streams of traffic moving in the same direction. Carelessly crossing a lane line puts one in jeop-

Warning pavement markings advise motorists of the existence of hazardous or potentially hazardous conditions. A dividing line that separates two-way traffic warns motorists of the potential hazard of a head-on collision with oncoming vehicles if that line is crossed. It is not necessarily a violation to cross that line when turning or passing another vehicle, but the motorist is warned to maintain caution.

6-1

Version 0.1


ardy of a sideswipe collision with vehicles in the adjacent traffic stream.

plement. An exception to this rule is that the back side of a reflectorized marker may be red, such that the red color is only visible by motorists approaching those markers from an incorrect direction.

Longitudinal lines can be characterized as follows: • • •

•

• •

Broken lines are permissive in character and may be crossed by a vehicle with due caution. Solid lines are restrictive in nature and should not be crossed except in case of an emergency. Solid double lines convey the same message as a single solid line, but with a greater degree of emphasis and conspicuousness necessitated by a particularly critical situation. A double line solid on one side and broken on the other conveys a message of restriction of movement across it from the solid-line side and a permission of movement across it from the broken-line side. Double lines consist of two lines equal in width and separated by a gap equal to the width of the line. Discontinuities in longitudinal lines, whether solid or broken, indicate by their absence locations where turns, merges, or diverges are expected to occur.

In general, the color of a marking should have the following connotations: •

- White should be used for regulatory markings. - Yellow should be used for all other markings. •

Longitudinal Markings. - Yellow is used for the longitudinal lines that mark the left edge of all divided roads and for both edges of one-way roads.Yellow is also used to divide traffic flowing in opposite directions on rural, high-speed roads. - White is used for the longitudinal lines that mark the right edge of all roads and to delineate lanes flowing in the same direction. White is also used to divide opposite traffic directions on two-way, undivided, single-lange roads in low-speed, urban settings.

Symbolic markings convey a roadway-oriented message to a motorist using a single or grouped set of discrete markings to represent the condition present. A turn arrow is an example of a symbol marking, advising motorists by its presence within a lane, the direction of travel that should be taken from that lane. In the context of this manual, diagonal lines such as a chevron or hatch marking are considered symbolic since they convey the same message symbolically to motorists as would be given by chevron and/or hazard marker signs. Worded markings, while not generally recommended, are classified as symbol markings.

Table 6-1 describes the various road types and the correct longitudinal-line applications. •

Symbols. - White should be used for all symbol markings.

6.1.4 CONFIGURATION All broken longitudinal lines have been configured to fit within an eight-meter module. When more than one longitudinal line is used within a given cross-section of roadway, the modules of each line should be situated such that they align transversely with each other across the roadway. Intermittent solid lines should begin and end to be compatible with the broken line module (see Table 6-3).

6.1.3 COLOR Painted pavement markings should be either white or yellow. Raised pavement markers should convey to motorists the same color message as the painted markings they replace or sup-

Version 0.1

Transverse Markings.

6-2


Table 6-1 Colors of Longitudinal Pavement Markings Left Edge of Travel Roadway 1 one-way (single or multilane) yellow 2 two-way, undivided, single lane yellow in each direction 3 two-way, undivided, multilane yellow in each direction Road Configuration

Right Edge of Travel Lane-Dividing Lines Roadway yellow1 white (if multilane) white white

a. white (same direction) b. solid double yellow between directions white

4 two-way, divided, multilane in yellow white each direction Notes: 1 The Department recognizes that the MUTCD and other authorities specify a white right edge of pavement marking in such roadway configurations, but in these cases prefers the use of yellow.

- If the existing marking is well worn and would be relatively inconspicuous in comparison to the new pavement markings, then the new pavement markings may be applied without regard to the existing markings (care should be taken in considering the relative conspicuousness between the new and old markings at a later point in time when the new markings have been in service and begin to loose some of their original conspicuousness). This does not apply to raised pavement markers. - If practical to do so, existing conflicting markings should be completely removed from the pavement surface. - If the roadway section is scheduled for future resurfacing, but such is far enough in the future that intermediate pavement marking maintenance is necessary, then the existing markings may be retained and maintained even though they do not fully comply with this manual.

6.1.5 IMPLEMENTATION OF THIS PAVEMENT-MARKING GUIDANCE The pavement marking configurations indicated in the following sections are intended for use in newly constructed roadway projects. In such areas, the pavement marking configurations and locations should be followed as prescribed in this manual. However, when pavement markings on existing roadways are in need of upgrade or maintenance, engineering judgment should be exercised in applying the requirements contained herein. The following guidelines should be considered in such cases: •

•

•

When existing pavement markings are either identical to or will be completely covered by new markings as required by this manual, the new markings should be reinstalled over existing markings. When existing markings are in excess of what is required by this manual (such as additional lane arrows), the existing markings may be retained but not maintained, being allowed to gradually fade from the pavement providing that their presence will not create confusion. When existing markings are of a different configuration than those required by this manual the most appropriate of the following actions should be taken:

6.2

REGULATORY MARKINGS

Regulatory pavement markings dictate action that must be taken by a driver when the markings are encountered. Actions contrary to these markings constitute a traffic violation subject to enforcement. Regulatory markings exist in transverse, longitudinal, and symbol types of pavement markings.

6-3

Version 0.1


6.2.1 STOP LINE MARKING 601

stopping and a clear view of conflicting traffic consistent with the fact that the provision of a STOP control implies limited visibility. The preferred position is one meter from the near edge of the intersecting roadway. However, the STOP LINE may be located within a range of 500 millimeters up to 10 meters from this edge to take account of specific aspects of the intersecting roadway. For example, a larger setback may be needed to accommodate turning vehicles when one or both of the intersecting roadways are narrow or the intersection is skewed. It should be positioned not less than one meter in advance of PEDESTRIAN CROSSING marking 603 when such is located at a signalized road junction and preferably not less than three meters in advance of a signalized midblock PEDESTRIAN CROSSING (see Figures 6-1 and 6-2 and Section 8.2).

Marking 601 imposes a mandatory requirement that a driver come to a full and complete stop immediately behind that line and is always used in conjunction with a STOP sign 301 or a red traffic signal. In the event that the STOP sign is missing or a traffic signal is unlighted due to temporary malfunction, the STOP LINE alone has the full significance of STOP sign 301. STOP LINE marking 601 should not be crossed without stopping except in the case of a green traffic signal or when directed by a Traffic Police officer. It is thus of critical importance that if a STOP sign or traffic signal is intentionally removed from service that the associated STOP LINE be removed from the pavement as well. STOP LINE marking 601 should be a continuous solid white line transverse and completely across the full width of the traveled portion of the roadway that is controlled by a STOP sign or traffic signal. The standard width of STOP LINE marking 601 should be 300 millimeters. On highspeed rural roads where added conspicuousness is desired its width may be increased to 500 millimeters. Marking 601 should be positioned on the roadway at the location best suited for safe 9m

L

6.2.2 GIVE WAY LINE MARKING 602 Marking 602 imposes a mandatory requirement that a driver should, when in conflict, stop at the point marked by the line and yield right of way to vehicular and/or pedestrian traffic crossing his intended path. Marking 602 should always be used in conjunction with GIVE WAY sign 302 9m min

L

No Passing Line 611

Stop Line 601 L No Passing Line 611

See Table 6-3 for L values

9m Dividing Line 652

Figure 6-1 Use of No Passing Line 611 at Junction

Version 0.1

6-4


1000 preferred 500 min 300 (500)

NO PASSING LINE 611

Detail 6-2-1: STOP LINE marking 601

1000 preferred 500 min 300 (500)

NO PASSING LINE 611

Detail 6-2-2: GIVE WAY LINE marking 602

NO PASSING LINE 611

500

GIVE WAY LINE 602

500

6000 preferred 3000 min

250 min 3000 min Detail 6-2-3: PEDESTRIAN CROSSING marking 603

Figure 6-2 Transverse Regulatory Pavement Markings (see also Figure 6-3 and Figure 6-4)

6-5

Version 0.1


and GIVE WAY TO PEDESTRIANS sign 303. In the event that a GIVE WAY or GIVE WAY TO PEDESTRIANS sign is missing, the GIVE WAY LINE alone has the full significance of the GIVE WAY signs 302 or 303.

requirement that the driver exercise a high degree of care and caution in the vicinity. PEDESTRIAN CROSSING marking 603 should be a broken white line transverse and completely across the full width of the roadway and shoulders. The configuration of the line should be 500 millimeters line and 500 millimeters gap. The gap orientation should be aligned parallel with the direction of vehicular travel at the crossing. The minimum width of line, measured perpendicular to the axis of pedestrian travel, should be 3 meters. This width may be increased if large volumes of pedestrians are present. A width basis of 0.5 meters for every 100 pedestrians per hour may be used (see Figures 6-2, 8-4, and 8-7).

GIVE WAY LINE marking 602 should be a broken white line transverse and completely across the full width of the traveled portion of the approach roadway that is controlled by a GIVE WAY sign 302 or GIVE WAY TO PEDESTRIANS sign 303. The standard width of a GIVE WAY LINE is 300 millimeters. On high-speed rural roads where higher conspicuousness is desired, its width may be increased to 500 millimeters. The configuration of the GIVE WAY LINE should be a repeated pattern of 600 millimeters of line separated by 300 millimeters of gap.

The use of PEDESTRIAN CROSSING marking 603 should be carefully considered. An engineering study should be made for their use away from signal-controlled intersections. PEDESTRIAN CROSSING marking 603 may only be installed with the approval of the Department.

Marking 602 should be positioned on the roadway at the location best suited such that, if on approach to a junction the driver sees that this way is not clear of opposing traffic, he may stop at the GIVE WAY LINE and have a clear view of approaching crossroad traffic. It should be located not less than one meter (500 millimeters absolute minimum) from the nearest edge of the intersecting roadway. When used in conjunction with a PEDESTRIAN CROSSING marking 603, the GIVE WAY LINE should be located in advance a distance of 3 meters minimum and 6 meters preferred (see Figures 6-1 and 6-2 and Section 8.2).

6.2.4 NO PASSING LINE MARKING 611

6.2.3 PEDESTRIAN CROSSING MARKING 603

When used in place of or on the right side of marking 611, DIVIDING LINE marking 652 imposes a mandatory requirement that drivers should not cross or drive on the left-hand side of such marking (with the exception of left turns to or from private direct access to a property). It is used to demarcate sections of two-way roadways where an extreme hazard could result if vehicles are permitted to even temporarily use an oncoming traffic lane.

Marking 603 when used at a location not controlled by traffic signals imposes a mandatory requirement that a driver must yield right of way to pedestrians crossing the roadway carrying the same meaning as the GIVE WAY TO PEDESTRIANS sign 303 whether that sign is present or not. Regardless of its location, within marking 603 pedestrians always have right of way over vehicles and vehicles must yield to pedestrians within the crossing. When used at a signal controlled crossing, marking 603 warns drivers of a pedestrian crossing location with the likely presence of pedestrians near the road and invokes a

NO PASSING LINE marking 611 should be a longitudinal solid yellow line, running continuously on or near the centerline of the roadway. It should be 100 millimeters wide for posted speeds below 50 km/h and 150 millimeters wide for posted speeds above 50 km/h. It should be used to delineate unsafe passing situations in areas where the barrier sight distances are restricted to less than the distances shown in Table 6-2. In such uses, marking 611 should be placed on the right side of DIVIDING LINE marking 652 for the entire length of roadway that substandard barrier sight distances exist. NO PASSING LINE

Version 0.1

6-6


Table 6-2 Use of No Passing Line 611 on Curves Operating Speed Minimum Barrier Sight Distance (km/h) (meters) 40 120 60 175 80 250 100 320 NOTES: 1. Barrier sight distance is defined as the distance that a driver with an eye height of 1.1 meters can view a 1.1-meter high object in the oncoming lane. NO PASSING LINE marking 611 should be used on horizontal or vertical curves to mark sections of two way roads where the actual barrier sight distance on a roadway is less than the minimum required. 2. Barrier sight distances are different than passing sight distances used in roadway design. Adequate passing sight distance defines the capability to safely begin and complete a passing maneuver. The barrier sight distance is representative of the distance necessary to abort a passing maneuver. 3. Engineering judgment must be applied in using a NO PASSING LINE. Longer lines than those resulting from application of the above minimums may be justified. When two sections of NO PASSING LINE are separated by less than the minimum barrier sight distance, for the appropriate operating speed, the two lines should be extended and joined.

marking 611 should also be used for purposes of traffic control in advance of any controlled junction (signal, stop, give way or pedestrian) on a two-way roadway. It should replace DIVIDING LINE marking 652 starting at the distance given in Table 6-3 as measured from the STOP LINE marking 601, GIVE WAY LINE marking 602, or the near edge of intersecting roadway. Marking 611 should continue towards the junction until intersecting those lines, other painted or curbed island, or the nearest edge of the intersecting roadway.

is used to channelize one-way traffic within a lane in areas where lane changes would be hazardous due to roadway configuration. CHANNELIZING LINE marking 612 should be a longitudinal solid white line running continuously on the line dividing two lanes of travel in the same direction. It should be 100 millimeters wide for posted speeds below 50 km/h and 150 millimeters wide for posted speeds above 50 km/h. It should be used in any situation where there is a significant safety or functional benefit that can be achieved if drivers are required to remain in their current lane over some distance. Such situations would occur in advance of traffic signals or roundabouts. Exclusive turn lanes and freeway or other free-flow ramps where one or more lanes are dropped from the main roadway will have application for marking 612. In such cases a 200-millimeter line width should be used. When used in advance of a signalized junction or

6.2.5 CHANNELIZING LINE MARKING 612 When used in place of LANE LINE marking 654, marking 612 imposes a mandatory requirement that drivers not cross that marking from either side. Marking 612 should only be used between streams of traffic traveling in the same direction. It

Table 6-3 Use of No Passing Line 611 and Channelizing Line 612 at Junctions Operating Speed Minimum Length (L) (km/h) (meters) 30 40 60 80 100

9 18 27 36 54

NOTES: 1. See Figures 6-1, 6-2, 6-3, and Chapter 8. 2. Values of L shown are minimum. Greater values may be justified based on engineering judgement. Increases should be made in multiples of 9 meters.

6-7

Version 0.1


•

a roundabout, marking 612 should be applied for the same limits of minimum length as NO PASSING LINE marking 611 as given in Table 6-3 (see Figures 6-3 and 8-2 to 8-7).

Specially developed types of EDGE LINE marking 613 which are designed to produce an audible and/or vibratory effect when driven over may be specified. Such an application may be warranted if a problem occurs on a long section of rural road with drivers losing attention or becoming drowsy and drifting towards the edge of roadway (see also Section 6.3.1).

6.2.6 EDGE LINE MARKING 613 Marking 613 imposes a mandatory requirement that drivers not cross that marking for purposes of driving or parking on the opposite side except in the case of an emergency. Marking 613 should be used to define the edge of pavement when such is not safe or convenient to define by use of a raised curb or barrier. It should also be used to separate a traveled lane from a paved shoulder that must remain accessible in case of emergency, but that must not be otherwise used for driving or parking.

6.2.7 LANE DIRECTION ARROW MARKINGS 614 TO 619 (INCLUDING STRAIGHT, RIGHT TURN, LEFT TURN, STRAIGHT/RIGHT, STRAIGHT/LEFT, AND RIGHT/LEFT)

EDGE LINE marking 613 should be a longitudinal solid white or yellow (depending on roadway configuration) line running continuously along the right side of the outermost traffic lane of a roadway and a longitudinal solid yellow line running continuously along the left side of the innermost traffic lane of a divided (or one-way) roadway. Table 6-1 provides detailed guidance for edge line colors. EDGE LINE marking 613 should be 150 millimeters wide for posted speeds less than 70 km/h and 200 millimeters wide for posted speeds more than 70 km/h. Since crossing of marking 613 is not permitted, care must be taken to provide discontinuities at points where access is intended. If continuous access to a length of roadside area is intended, then marking 613 should not be used. In such instances when edge delineation is still desired, PARKING ENVELOPE LINE marking 620 should be used.

Markings 614, 615, and 616 impose a mandatory requirement that drivers must travel only in the direction indicated by the arrow if they are in the lane marked by the arrow. Drivers not wishing to travel in the direction indicated by the arrow must move to an adjacent lane if not otherwise prohibited from doing so. Markings 614, 615, and 616 indicate a single, mandated direction of travel for a lane. Markings 617, 618, and 619 impose a mandatory requirement that drivers must travel only in one of the two directions indicated by the arrow from the lane in which the arrow is marked. Drivers not wishing to travel in one of the directions must move into an adjacent lane if not otherwise prohibited from doing so. When any of the markings 614 to 619 are located adjacent to a CHANNELIZATION line marking 612 drivers must stay in their lane and continue in the direction, or one of the directions, indicated by the arrow.

In addition to a regulatory function EDGE LINE marking 613 performs other important safety functions: •

•

Provides continuous demarcation of the edge of the traveled way, reducing the tendency of drivers to drift off the road, especially at night and/or under adverse weather conditions. Provides an indication of turn or exit points from the main road at points of discontinuity in the line.

Version 0.1

Where not otherwise prohibited, provides guidance to pedestrians and bicyclists.

RIGHT TURN ARROW marking 615 and LEFT TURN ARROW marking 616 should be used to mark lanes that are exclusively turn lanes at signalized intersections. Markings 615 or 616 should not be used to mark exit lanes at gradeseparated junctions (although they may be used at the terminal junctions of such exits).

6-8


100 (150) DIVIDING LINE marking 652 100 (150) 100 (150) 100 (150)

Detail 6-3-1: NO PASSING LINE marking 611 (variations shown)

100 (150) 100 (150) 100 (150)

100 (150) (200)

Detail 6-3-2: CHANNELIZING LINE marking 612

150 (200) Detail 6-3-3: EDGE LINE marking 613 (line is sometimes white; see Table 6-1 for guidance)

1000

1000

100 Detail 6-3-4: PARKING ENVELOPE LINE marking 620

500

100

1000

100

Detail 6-3-5: PARKING LINE marking 621

Direction of Travel

Figure 6-3 Longitudinal Regulatory Pavement Markings (see also Figures 6-2 and 6-4)

6-9

Version 0.1


All LANE DIRECTION ARROW markings should be white in color. All LANE DIRECTION ARROW markings should be centered transversely within the lane to which they apply such that the transverse extremities of the marking are equidistant from the lane edge on each side.

The above are offered as guidelines and are not intended to preclude the use of good engineering judgment. For example, advance arrows should not be used if they may cause confusion due to an entering side road. Other arrow arrangements can be used in a given situation if needed for clarity. However, overuse of arrows is generally indicative of confusing geometry that will unlikely be clarified by additional lane arrows. Arrow markings should not be used on freeways or similar free flowing roadways where overhead signs and longitudinal lines should provide sufficient delineation.

All lanes at the approach to a signalized intersection should have one arrow (one of markings 614, 615, 616, 617, 618, or 619) positioned in each lane in line with one another transversely. This primary row of arrows should be located as close to the junction as possible while still giving a clear indication of all adjacent lanes with respect to one another. In any case, the row of arrows should be positioned so as to be entirely within the limit of the CHANNELIZING LINE marking 612. Additional LANE DIRECTION ARROW markings should be positioned in advance of this row of markings in accordance with the following guidelines: •

STRAIGHT/RIGHT (or LEFT) ARROW marking 617 (or 618) should not be used to indicate the point where turning lanes are added to the basic through lanes of a roadway. They also should not be used to indicate direct turning points from a mainline lane onto a side road at mid-block locations.

For additional exclusive turn lane(s) created at a junction:

Regulatory pavement arrow markings are illustrated in Figure 6-4. Examples of the use of LANE DIRECTION ARROWS 614 to 619 are illustrated in Figures 8-2 to 8-7.

- At the point where the lane(s) are first developed to their full width (but not closer than 25 meters clear of the primary arrow). - At one intermediate point providing the clear spacing between arrows is not less than 25 meters. •

6.2.8 PARKING ENVELOPE LINE MARKING 620 Marking 620 imposes a mandatory requirement that drivers parking their vehicles within a marked area park such that no part of their vehicle encroaches upon the pavement area outside a parking envelope so marked. A driver who parks such that any part of his vehicle overhangs marking 620 should be considered improperly parked.

For basic lanes that are not exclusively straight-ahead only lanes: - At 25 meters clear and at 55 meters clear in advance of the primary arrows, or - In line transversely with additional exclusive turn-lane arrows.

•

PARKING ENVELOPE LINE marking 620 should be a longitudinal broken white line 100 millimeters wide. The configuration of the PARKING ENVELOPE LINE should be a repeated pattern of one meter of line separated by a one-meter gap. It should be located at the edge of pavement adjacent to areas where parking is permitted, but should not be used if the physical space available for parking is less than 2.2 meters wide (see Figures 6-3 and 8-1 to 8-3).

For straight-ahead-only basic lanes approaching a standard signalized intersection: - No additional STRAIGHT ARROW marking 614.

When LEFT TURN ARROW marking 616 is used to mark a midblock left-turn or U-turn lane, STRAIGHT ARROW marking 614 should not be used on the mainline.

Version 0.1

PARKING ENVELOPE LINE marking 620 is intended for use in areas of low-density parking

6-10


Detail 6-4-1:

300 mm

300 mm

Straight Arrow 614

Right Turn Arrow 615

Left Turn Arrow 616

300 mm

Detail 6-4-2:

Straight/Right Arrow 617

Straight/Left Arrow 618

300 mm Left/Right Arrow 619

Figure 6-4 Typical Regulatory Arrow Pavement Markings (see also Figure 6-2 and 6-3)

6-11

Version 0.1


where the delineation of individual parking spaces is not considered necessary. A secondary benefit of the PARKING ENVELOPE LINE is to serve the function of EDGE LINE marking 613, by delineating the edge of pavement, but without the prohibition of crossing that line for purpose of parking. The most common usage of the PARKING ENVELOPE LINE will be the marking of on-street parking areas in residential communities and other such locales where parking spaces are not in short supply and as such a more regimented parking arrangement is not warranted.

apply irrespective of the material used to surface the parking area to be marked. A PARKING SPACE LINE marking 621 may also be used to designate zones within lay-bys or along curblines that are designated as stopping areas for certain classes of vehicles.

6.3

Warning pavement markings advise motorists of the existence of hazardous or potentially hazardous conditions. These markings do not carry a mandatory requirement for specific action. However, these markings do convey a message of warning and a willful disregard of those warnings may constitute a violation when drivers fail to maintain adequate and safe control of their vehicle. Warning markings exist in transverse, longitudinal, and symbol types of pavement markings. VISIBILITY PAINTING marking 691 and TEXT SYMBOL marking 695 also have warning functions. See Sections 6.6.3 and 6.8.2, respectively, for discussion of those markings. Warning markings are illustrated in Figures 6-5 to 6-7 and their application is further illustrated in the various figures in Chapter 8.

6.2.9 PARKING SPACE LINE MARKING 621 Marking 621 imposes a mandatory requirement that drivers parking their vehicles within a marked parking space park such that their vehicle is wholly within the lines defining the limits of the parking space. A driver who parks such that any part of his vehicle is on, over, or beyond marking 621 (or an imaginary line connecting the ends of a series of marking 621 lines) should be considered improperly parked. PARKING SPACE LINE marking 621 should be a solid white line 100 millimeters in width. It should extend from the curb line (if a curb is present) and end at the edge of the designated parking bay. For parallel parking space delineation the end of the PARKING SPACE LINE should have a 500-millimeter long L-shape for end-marking of a parallel parking bay, and a 1000 millimeter long T-shape for intermediate lines. Perpendicular and angled parking space markings generally do not require end shapes since the ends of the more closely spaced PARKING SPACE LINES should clearly delineate the parking bay limits.

6.3.1 RUMBLE STRIPS MARKING 650 Marking 650 may be used to advise motorists through visibility, sound, and vibration of the presence of a critical regulatory or warning device when this marking is located within a traveled way. When marking 650 is used within a shoulder or other road side area they provide a warning to drivers that they are drifting off of the traveled roadway. RUMBLE STRIPS marking 650 should be positioned transversely to the direction of vehicle travel. When used within the traveled roadway, they should be formed of or topped with yellow thermoplastic material (for purposes of conspicuousness and to distinguish them from a STOP LINE marking 601) built up at least 5 millimeters, but no more than 15 millimeters, above the roadway surface. The width, spacing, and number of RUMBLE STRIPS used in a single installation may vary to suit conditions as determined appropriate by an engineering study. As a guide-

PARKING SPACE LINE marking 621 should be used to mark individual parking spaces in areas where parking space availability is at a premium and the definition of parking spaces will give an orderly and more efficient usage of area available for parking. The PARKING SPACE LINE should always be used to mark parking spaces that are subject to payment for usage. These provisions

Version 0.1

WARNING MARKINGS

6-12


NO PASSING LINE 611

2000

=

3800 for 60 km/h

=

5200 for 80 km/h 300

=

8000 for 100 km/h

=

Detail 6-5-2: SPEED HUMP marking 651

Detail 6-5-1: RUMBLE STRIPS marking 650 3000

6000 100 (150)

Detail 6-5-3: DIVIDING LINE marking 652 3000

6000

100 (150) (200)

Detail 6-5-4: LANE LINE marking 654 1170

2870

20°

20°

Detail 6-5-5: LANE ENDS ARROW 656 Direction of Travel

Figure 6-5 Warning Pavement Markings

6-13

Version 0.1


EDGE LINE marking 613 or CHANNELIZING LINE marking 612

EDGE LINE marking 613 or NO PASSING LINE marking 611 150

150

Detail 6-6-1: CHEVRON marking 657

Detail 6-6-2: HATCH marking 658

W

EDGE LINE Marking 613

45° 45° t

t

Physical Nose

Theoretical Nose

Detail 6-6-3 Direction of Travel CHEVRON DIMENSIONS Operating Speed (km/h) 40 60 80 100

W (millimeters) 200 300 500 1000

S (meters)

t (millimeters)

1.0 1.5 2.5 5.0

150 150 200 200

Figure 6-6 Combined Regulatory and Warning Pavement Markings as Painted Islands

Version 0.1

6-14


120km/h Y

DS Design speed

30m

DS

Y

Y/4

110

30

7.50

90

25

6.25

70

20

5.00

50

14

3.50

30

10

2.50

275m

(DS) 110km/h

40m

245m

100km/h 205m

25m

DS 90km/h

Y/4

180m

Y/4

80km/h

35m

145m 20m

Y Y/4

DS 70km/h 125m 60km/h

25m

100m 14m

DS 50km/h

10m

86m

40km/h

16m

Y/4

DS 30km/h

300mm (typ)

70m 60m

30km/h

60m

Junction or other transverse hazard

Figure 6-7 Guideline for Using Rumble Strip Marking 650 for Speed Reduction

6-15

Version 0.1


line, a basic rumble strip configuration is recommended to consist of five transverse yellow markings 300 millimeters wide spaced such that at prevailing traffic speeds all five markings will be traversed during an approximately one-second period. They should be positioned within the first one-third of the clear visibility distance to the sign of which they forewarn (see Figure 6-5).

•

RUMBLE STRIPS should not be used within a traveled way unless, after all other means of standard traffic control devices have been evaluated, the Department agrees that their use is the only reasonable solution to an identified problem. Their use as such will generally not be permitted on new construction, but rather as a retrofit to a particular problem area.

A more acceptable usage of RUMBLE STRIPS marking 650 will be for use outside of traveled ways. In such instances, drivers remaining within the traveled way are not affected by them, but rather they affect only those drivers who are traveling (illegally and/or accidentally) in areas where they should not be. One particular useful application is on shoulders of freeways or other roadways, especially in long, straight stretches of rural roads. On such roadways drivers may become bored or sleepy and slowly drift into a shoulder area. The presence of RUMBLE STRIPS in the shoulder may assist a driver in regaining attention before completely leaving the roadway (see Section 6.2.6).

•

Sets of RUMBLE STRIPS markings 650, as described above, may be specified in order to reinforce the need for drivers to significantly reduce their speed. Such circumstances will commonly occur on high speed and/or downhill approaches to STOP or GIVE WAY control conditions. A typical requirement might involve a need to reduce speed from around 120 km/h to the order of 30 km/h a short distance from the point of control or a change of direction. The principle to be used provides for a series of sets of five transverse markings spaced so that each set will be traversed during an approximately one-second period at progressively decreasing speeds. Each set of markings should in turn be separated from the last and/or next set by a distance without markings that will be transversed during a period of 1 to 2 seconds. The configuration and number of sets of five markings required for a specific site will be dictated by the approach speed and the speed reduction required. Figure 6-7 illustrates a sequence of sets of RUMBLE STRIPS marking 650 spaced according to these principles. The number of sets and the overall installation can be determined from the figure. Alternative designs for rumble strips must be approved by Department.

6.3.2 SPEED HUMP MARKING 651 Marking 651 should be used to warn motorists of the presence of a speed hump in the roadway. (The application, geometric design, and construction of speed humps is subject to engineering evaluation and selective usage.) SPEED HUMP marking 651 should be a broken yellow line transverse and completely across the full width of the roadway and shoulders. The configuration of the line should be 500 millimeters line and 500 millimeters gap. The gap orientation should be aligned parallel with the direction of vehicular travel. The minimum width of line, measured perpendicular to the axis of the speed hump should be two meters. The line should be positioned such that the whole of the line is visible to approaching traffic and not hidden on the far side of the speed hump. When used on two-way roadways where the hump is visible from both directions of approach, the line may be widened to provide a minimum of two meters of visible line from each approach direction (see Figure 6-5).

The disadvantages of RUMBLE STRIPS within a traveled way are as follows: •

Their effect on small, lightweight vehicles such as motorcycles may be pronounced and undesirable.

Version 0.1

When used in built-up areas, residences and businesses may find the constant noise and vibration to be disturbing and a source of irritation. Most motorists do not need rumble strips to be made aware of the situation being warned. However, all motorists are affected by driving over them.

6-16


NO PASSING LINE marking 611 and/or CHANNELIZING LINE marking 612 should be used on each approach to the speed hump for an appropriate distance as given in Table 6-3.

of gap. It should be 100 millimeters wide for posted speeds below 70 km/h and 150 millimeters wide for posted speeds above 70 km/h. A LANE LINE should be used on one-way travel ways more than 6.0 meters in width. A LANE LINE should not be used (or should be discontinued in a tapered section) to mark a lane that will be less than 2.7 meters in width (see Figures 6-5 and 8-2 to 8-16).

6.3.3 DIVIDING LINE MARKING 652 Marking 652 should be used to warn motorists that vehicles traveling on the other side of the line are traveling in the opposite direction. Motorists may cross marking 652 to pass another vehicle, but only when it is safe to do so.

LANE LINE marking 654 should be replaced with a regulatory CHANNELIZING LINE marking 612 in circumstances where warranted (see Sections 6.2.5 and 6.3.2) in areas where changing lanes is not permitted.

DIVIDING LINE marking 652 should be a longitudinal broken yellow line running continuously on or near the centerline of the roadway. Its configuration should be a repeated pattern of 3 meters of line followed by 6 meters of gap. It should be 100-millimeters wide for posted speeds below 50 km/h and 150-millimeters wide for posted speeds above 50 km/h. A DIVIDING LINE should be used on all two-way roadways with a travel width of 5.5 meters or more. It may be used continuously or intermittently on roads of lesser widths when an engineering assessment determines that such is beneficial for reason of safety.

Neither a LANE LINE nor a CHANNELIZING LINE should be used within a junction. When guidance within a junction is required, GUIDE LINE marking 680 should be used (see Section 6.4.1).

6.3.5 LANE END ARROW MARKING 656 Marking 656 should be used to warn motorists that a lane on a multilane roadway is ending ahead and that they should move out of that lane in the direction indicated at the earliest opportunity that it is safe to do so.

DIVIDING LINE markings 652 should be replaced or supplemented with a regulatory NO PASSING LINE marking 611 in circumstances where warranted (see Sections 6.2.4 and 6.3.2) when crossing the DIVIDING LINE from one or both sides is not permitted. Neither a DIVIDING LINE nor a NO PASSING LINE should be used within an intersection of two public roads where traffic is permitted to turn across an opposing direction of travel (see Figure 8-1).

LANE END ARROW marking 656 should consist of a white straight arrow oriented at a 20 degree rotation to the longitudinal axis of the lane. The arrow should be centered in the lane such that its extremities are equidistant from the lane edge on each side (see Figures 6-5 and 8-7).

6.3.4 LANE LINE MARKING 654

LANE END ARROW marking 656 is to be used when a long-running lane on a multilane roadway ends. It should also be used at the end of a parallel-lane-type entrance ramp. It is not intended for use on a tapered entrance ramp. The LANE END ARROW should be repeated in a series of two or preferably three markings. The last of the arrows in the series should be positioned at the end of the lane just prior to the point where the lane begins to decrease in width. The spacing between each LANE END ARROW should be as given in Table 6-4.

Marking 654 should be used to warn motorists of the presence of two or more traffic lanes traveling on a roadway in the same direction. Motorists may cross marking 654 to change lanes, but only when it is safe to do so. LANE LINE marking 654 should be a longitudinal broken white line running continuously on a line separating two lanes of travel in the same direction. Its configuration should be a repeated pattern of 3 meters of line followed by 6 meters

6-17

Version 0.1


Table 6-4 Lane End Arrows Spacing Operating Speed Spacing (km/h) (meters) 40 60 80 100

two way roadway becomes divided and viceversa. HATCH markings may be used to mark the shoulders of particularly dangerous curves, lane ends, or roadside obstructions. However, these situations should be thoroughly evaluated by an engineering study and HATCH markings used only if it is determined that a significant hazard exists and that HATCH markings may significantly contribute to the delineation and warning of the hazardous or unusual conditions. In such conditions consideration should be given to the use of RUMBLE STRIPS marking 650. The routine usage of HATCH markings should be avoided.

24 32 40 48

6.3.6 CHEVRON MARKING 657 Marking 657 should be used to provide warning to motorists of a divergence of traffic lanes traveling in the same direction. CHEVRON marking 657 should consist of diagonal white lines arranged in a chevron pattern as depicted in Figure 6-6. The CHEVRON should point towards the oncoming traffic such that the sloping legs of the CHEVRON are seen to split the diverging streams of traffic, “pushing” them away from one another. Marking 657 should be repeated within a gore area beginning at the theoretical nose (painted nose) of an exit or divergence point and cease at the physical nose. CHEVRON marking 657 should not be used within the gore area of converging streams of traffic.

HATCH marking 658 should only be used in areas not intended for travel or parking and should always be separated from a travel area by a NO PASSING LINE marking 611 or EDGE LINE marking 613.

6.4

GUIDANCE MARKINGS

CHEVRON marking 657 should only be used in areas not intended for travel or parking and should always be separated from a travel area by an EDGE LINE marking 613 or a CHANNELIZING LINE marking 612.

Guidance pavement markings provide help to motorists in understanding the path that they are intended to follow where the way may not be otherwise evident. Guidance pavement markings do not carry a mandatory requirement nor convey an explicit message of warning. Only longitudinal broken lines and TEXT SYMBOL marking 695 (see Section 6.8.2) are used for guidance markings. Guidance markings are illustrated in Figure 6-8.

6.3.7 HATCH MARKING 658

6.4.1 GUIDE LINE MARKING 680

Marking 658 should be used to provide warning to motorists to stay clear of a physical danger that is present adjacent to their travel lane.

Marking 680 may be used within a junction (intersection or roundabout) to provide guidance to road users. Except in the case of roundabouts, usage of this marking is optional and should only be considered in instances of nonstandard or confusing geometry, including sheer junction size.

HATCH marking 658 should consist of repeated diagonal white lines situated as depicted in Figure 6-6. The dimensions and layout requirements for the HATCH marking should be similar to those shown for the CHEVRON marking 657 as shown in Figure 6-6. The HATCH markings should be oriented such that if they were raised barriers, they would deflect traffic back into the lane from which they came. A common usage of HATCH markings is in a median or gore area that separates traffic that is moving in opposite directions of travel. Such would be the case where a Version 0.1

GUIDE LINE marking 680 should be a longitudinal broken white line that follows one or both edges of the most efficient path (from the standpoints of safety and/or capacity) that a vehicle should follow through an intersection. Its configuration may vary to suit conditions but a recommended configuration is a repeated pattern of 500 millimeters of line followed by 1500 millimeters

6-18


500

1500

100

Detail 6-8-1: GUIDE LINE marking 680 1000

150 (200)

3000

Detail 6-8-2: CONTINUITY LINE marking 681

Direction of Travel

Figure 6-8 Guidance Pavement Markings

of gap. A GUIDE LINE should be 100 millimeters wide.

6.4.2 CONTINUITY LINE MARKING 681

The primary usage of GUIDE LINE marking 680 will be:

Marking 681 may be used to provide guidance for through traffic at discontinuities in the pavement-edge delineation. Its use is optional and should only be considered in instances where a curving roadway geometry and/or a long break in the continuity of the edge of pavement delineation may be confusing or misleading to a driver.

•

• •

To provide turning guidance, particularly for left-turning traffic, at wide intersections or where the intersecting roadways meet at an angle significantly different than 90 degrees and particularly when there is more than one turning lane. To provide alignment guidance across a wide or complex junction when there is a shift in the through-alignment across the junction, To mark circulation lanes within a roundabout. In such instances a GUIDE LINE should be used within the “shadow” of the roadway median islands (see Figures 8-5, 86, and 8-8).

CONTINUITY LINE marking 681 should be a longitudinal broken white line that follows the edge of the through-lane of traffic across an exit ramp, a slip road exit, or an intersection. Its configuration should be a repeated pattern of 1 meter of line followed by 3 meters of gap. It should be 150-millimeters wide for posted speeds below 70 km/h and 200-millimeters wide for posted speeds above 70 km/h. As a general rule a CONTINUITY LINE marking should not be extended across an entrance ramp on a freeway or a slip road entrance. In such cases the convergence of the entering roadway edge line should provide a clear indication of the forward alignment of the mainline (see Figure 8-16).

The use of a GUIDE LINE within an intersection should be considered only in exceptional circumstances. Because a GUIDE LINE will almost always cross the path of one or more intersecting lanes of traffic, particular attention must be given to the appearance of the line(s) when viewed by drivers other than those whom they are intended to guide. Care must be taken to avoid the risk of the line(s) creating a confusing pattern that may mislead other drivers.

6.5

RAISED PAVEMENT MARKERS (RPM)

Raised pavement markers may be used to supplement or replace painted line pavement markings to provide increased visibility and better delin-

6-19

Version 0.1


eation. They are also effective at discouraging unnecessary lane changes. Examples of the use of raised pavement markers are illustrated in Figure 6-9.

•

6.5.1 GENERAL

•

•

There are two basic classifications of raised pavement markers: • •

•

Retroreflective (R). Nonretroreflective (N).

Areas regularly subjected to fog, dust, or blowing sand resulting in reduced visibility. Areas of heavy traffic volumes that rapidly deteriorate painted markings and that are disruptive to regularly maintain. Isolated areas that have low geometric-roadway-design standards for the traffic conditions prevailing and that are not scheduled in the near term for improvement. Isolated areas with documented high incidence of collision and/or low levels of lane discipline by drivers, particularly in curved or complex roadway geometry conditions. Long-term roadworks sites. Freeways (all markings on freeways should be supplemented by R markings). Unlighted rural roadways. Within nonweaving sections of roundabouts.

Retroreflective markers house a colored lens of retroreflective material that is designed to redirect a substantial portion of vehicular head lighting back at a driver for improved nighttime longrange visibility.

• •

Nonretroreflective markers do not exhibit retroreflective properties but do, under daylight or lighted conditions (street lights or headlights) display a white or yellow body color the same as painted lines.

Under one or more of the following conditions raised pavement markers are generally not recommended for use:

• •

• •

Retroreflective markers are used to supplement white or yellow painted lines or nonretroreflective markers.

•

Nonretroreflective markers are used to replace white or yellow painted marking. Where roadway lighting is not to a high standard, nonretroreflective pavement markings should be supplemented by retroreflective pavement markings.

6.5.2 RETROREFLECTIVE RPM MARKING R When a standard pavement marking number is followed by the letter R it means that the marking be supplemented by the use of retroreflective RPM (e.g., LANE LINE marking 654 R).

In Abu Dhabi, lane lines and channelizing lines on main, divided thoroughfares are typically marked with a combination of retroreflective and nonretroreflective raised pavement markers. On two-way secondary and sector roads, channelizing lines and no passing lines should be marked with paint. Nonretroreflective and reflective raised pavement markers may also be used in most other pavement marking applications when deemed appropriate by the designer and with the approval of the Department.

The following describe the use of RPM R in various pavement marking applications: •

•

The following conditions may warrant the use of raised pavement markers: •

Version 0.1

Low operating speeds. Across the entrance and exit points of freeway ramps and other intersecting connections to major roadways. On roadways scheduled for resurfacing within three years.

6-20

An RPM R should normally be used at 18meter intervals (2 times the 9-meter marking module). Shorter spacing may be justified in certain instances. For broken lines, the RPM R should be placed in line with the standard pavement markings, centered in the appropriate gap area of the line. When an RPM R is used to supplement a solid line it should be placed 100-millimeters


18000

Detail 6-9-1: CHANNELIZING LINE marking 612R

Detail 6-9-2: CHANNELIZING LINE marking 612N

18000

Detail 6-9-3: CHANNELIZING LINE marking 612N/R

18000

Detail 6-9-4: EDGE LINE marking 613R (line is sometimes white; see Table 6-1 for guidance)

3000

3000

3000

3000

6000

3000

3000

Detail 6-9-5: LANE LINE marking 654R

3000

3000

18000

Detail 6-9-6: LANE LINE marking 654N/R

White/Red RPM R

White RPM N

Yellow/Red RPM R

Direction of Travel

Figure 6-9 Use of Raised Pavement Markers (RPMs)

6-21

Version 0.1


•

• • •

clear of and on the traffic side of the line (such as EDGE LINE marking 613 R). When traffic utilizes the line on both sides (such as a NO PASSING LINE marking 611 R or CHANNELIZING LINE marking 612 R) an RPM R may be placed on each side of the line. Alternatively, an RPM R may be placed within the line. However, this will require masking the line at the RPM location when the line is painted and each time it is repainted, to prevent the RPM R from being obscured by paint. When RPM N are used for a dashed line, RPM R should be placed as they would with paint. Where RPM N are used in a solid line, an RPM R should be used in place of an RPM N at the appropriate interval. When RPM R are used on more than one longitudinal line on a roadway, they should be situated such that all RPM R are aligned transversely across the roadway.

nonretroreflective markers then both the R and N letter designation should be used (e.g., LANE LINE marking 654 R/N). The RPM N should be used to replace and simulate the painted part of a line. For broken line types, one RPM N should be placed at the point where the painted segment would begin and one RPM N should be placed at the point where the painted segment would end. Other RPM N should then be spaced equidistant between these such that the center-to-center spacing does not exceed one meter. For a solid line the RPM N should be spaced at one-meter intervals. Only two colors of RPM N should be used: • •

White markers should be used to replace white-colored painted markings. Yellow markers should be used to replace yellow-colored painted markings.

6.6

CURB PAINTING

Only three colors of RPM R should be used: • •

•

The application of paint to the top and face of a curb may be undertaken when authorized or directed by the Department. The painting of a curb can provide increased visibility and better delineation than concrete-colored curbs. Curb painting may also be used to supplement or replace the use of NO PARKING signs. Because curb painting involves the use of paint near the pavement surface, and because its use and applications are similar to pavement markings, curb painting is considered to be pavement markings within the context of this manual.

White (or clear) markers should be used in conjunction with all white-colored pavement markings as viewed by approaching drivers. Yellow markers should be used in conjunction with all yellow-colored pavement markings as viewed by approaching drivers. When used with a line having meaning to traffic in opposing directions, such as a DIVIDING LINE marking 652 R, the RPM R should be bidirectional. Red color should only be used on the back side of markers on one-way or divided roadways. This color should be viewable only to drivers entering or driving in the wrong direction on such a roadway. The red color of an RPM R should never be visible to legally operating traffic.

6.6.1 GENERAL Under certain circumstances the painting of curb faces can play a significant role in regulating traffic with respect to parking and in warning traffic of the presence of a raised curb. To retain the conspicuousness and function of a painted curb, maintenance is an ongoing and continual process carrying with it a significant cost implication.

6.5.3 NONRETROREFLECTIVE RPM MARKING N When a standard pavement marking number is followed by the letter N it means that the painted marking should be replaced by nonretroreflective RPM (e.g., LANE LINE marking 654 N). When retroreflective markers are used to supplement

Version 0.1

6.6.2 NO PARKING MARKING 690 Marking 690 is used to advise motorists of specific areas along a curbline where parking is pro-

6-22


hibited. The use of marking 690 imposes a mandatory requirement on a motorist that he not park his vehicle adjacent to a curbline so painted.

prohibits the parking of vehicles adjacent to curbs so marked. VISIBILITY PAINTING marking 691 should consist of painting the top and front face of a curb with alternating sections of black- and white-colored paint. The length of a black section and the length of a white section should be equal to each other. When precast curbs are used, each section (or every two sections in the case of short curb sections) may be painted with alternating colors such that the length of each color will be in the range of 500 millimeters to 900 millimeters to match individual curbs. When short curbs are used around curves the adjacent length of marking should be retained. Because of the stroboscopic effect of viewing alternating painting from a moving vehicle, curbs or barriers with an exposed front face higher than 400 millimeters should not receive marking 691 over a significant length of roadway. Where such high curbs or barriers are used, VISIBILITY PAINTING marking 691 should be limited only to discrete areas where added visibility is required.

NO PARKING marking 690 should consist of painting the top and front face of a curb with alternating sections of black- and yellow-colored paint. The pattern and lengths of the sections should be the same as described for VISIBILITY PAINTING marking 691. Painting of the curb should extend from the point where the parking restriction begins and should be a continuous, solid marking to the point where the parking restriction ends. Marking 690 may be used to supplement NO PARKING signs 377, 378, and 379 when such is required for additional emphasis of a no-parking area, or when geometry is such that the extent of the no-parking area is not clearly delineated by the use of signs only. Marking 690 may also be used alone to delineate no-parking areas. Such applications will be most likely in cases where no-parking areas are broken and interspersed among areas where parking is permitted. In such cases it may be difficult or impractical to regulate by signing and the use of curb painting may be more appropriate.

The primary benefit of VISIBILITY PAINTING marking 691 is the delineation of curbs in turning areas such as intersections, roundabouts, and traffic separator islands. The use of marking 691 on long stretches of straight curb on well-lighted roadways is of limited benefit from a traffic-safety standpoint. While such sections may receive VISIBILITY PAINTING, its use should be weighed against the initial and long-term costs of doing so.

It is not the intent of the Department that all curbs in Abu Dhabi where parking is prohibited be painted with NO PARKING marking 690 (nor signed with NO PARKING signs 377, 378, and 379). In areas where parking is clearly not permitted and motorists are complying with such restrictions, then no further parking prohibition measures in the form of signs or curb painting is necessary.

6.7

OBJECT MARKERS

6.7.1 OBJECT MARKER DESIGN

In locations where the engineer may wish to use NO PARKING marking 690 but no curbs are present, an EDGE LINE marking 613 should be used and will have the same effect as marking 690.

Object markers are used to mark obstructions within or adjacent to the roadway. When used, these markers should consist of an arrangement of one or more of the following designs:

6.6.3 VISIBILITY PAINTING MARKING 691

• • •

Marking 691 is used to improve the visibility of raised curbs and to warn motorists of the presence of those curbs. The use of marking 691 has no regulatory function and neither permits nor

Type 1 Type 2 Type 3

Type 1 markers consist of an all-yellow reflective diamond panel 450 mm in size. A variant of this

6-23

Version 0.1


marker type incorporates nine yellow reflector units in the panel. Each reflector unit should have a dimension of approximately 75 mm mounted symmetrically on a 450-mm diamond-shaped yellow panel. Type 1 markers may be larger if conditions warrant (see Figure 6-10, Detail 1).

approach to the obstruction should be given by appropriate pavement markings. Where the vertical clearance of an overhead structure exceeds the maximum legal height of a vehicle by less than 0.3 m, the clearance to the nearest 0.1 m on a regulatory sign should be clearly marked on the structure as well as on the advanced warning sign.

Type 2 is a striped vertical rectangle approximately 300 mm by 900 mm in size with alternating black and reflectorized yellow stripes sloping downward at an angle of 45° toward the side of the obstruction on which traffic is to pass. The minimum width of the yellow stripe should be 75 mm. Type 2 object markers with stripes that begin at the upper right side and slope downward to the lower left side are to be designated as “right” object markers (see Figure 6-10, Detail 2).

6.7.3 OBJECTS ADJACENT TO THE ROADWAY Objects not actually in the roadway may be so close to the edge of the road that a marker is required. These include guardrail ends, underpass piers, bridge abutments, handrails, and culvert headwalls. In some cases, a physical object may not be involved, but other roadside conditions such as narrow shoulder drop-offs, gores, small islands, and abrupt changes in the roadway alignment may make it undesirable for a driver to leave the roadway. Type 2 object markers are intended for use at such locations. The inside edge of the marker should be in line with the inner edge of the obstruction.

Type 3 markers indicate the end of a roadway. When it is determined that markers should be placed at the end of a roadway where there is no alternative vehicular path, a marker consisting of nine red reflectors, each with a minimum dimension of approximately 75 mm, mounted symmetrically on a 450-mm red diamond panel; or a 450mm diamond reflectorized red panel should be used. More than one marker or a larger marker may be used at the end of the roadway where conditions warrant. The minimum mounting height of this marker should be 1.20 m. Appropriate advance warning signs should be used (see Figure 6-10, Detail 3).

Standard warning signs should also be used where applicable. Typical applications of markers for roadside obstructions are shown in Figure 6-11.

6.8

6.7.2 OBJECTS IN THE ROADWAY

Text pavement markings may be used to supplement other pavement markings or signs only when specifically authorized or directed by the Department.

Obstructions within the roadway should be marked with a Type 1 or Type 2 object marker. For additional emphasis, a large surface such as a bridge pier may be painted with diagonal stripes, 300 mm or more in width, similar in design to the Type 2 object marker. The alternating black and reflectorized yellow stripes should be sloped down at an angle of 45° toward the side of the obstruction that traffic is to pass. The minimum mounting height should be 1.20 m.

6.8.1 GENERAL The use of text pavement markings should be strictly limited to situations where no other option to present or reinforce the required message to drivers is available. No specific applications for such markings are anticipated. The provision of such markings in this manual should not be taken as an encouragement for their use. Rather, they are described herein to provide a standard should there be a requirement for such in an isolated instance.

Appropriate signs directing traffic to one or both sides of the obstruction may be used in lieu of the object marker. In addition to markings on the face of an obstruction in the roadway, warning of

Version 0.1

TEXT PAVEMENT MARKINGS

6-24


Detail 6-10-1: Type 1 75-mm yellow reflectors

9 mm 0 13 mm 0

13 mm 0

Yellow reflective background

450 mm by 450 mm

450 mm by 450 mm

Detail 6-10-2: Type 2

Detail 6-10-3: Type 3 Red background

75-mm red reflectors

13 mm 0

900 mm

9 mm 0 13 mm 0

170 mm

45º

140 mm 70 mm

450 mm by 450 mm

300 mm

Left object marker

Right object marker

Figure 6-10 Object Markers

grounds which are then distorted by stretching five times in the vertical direction while maintaining an unaltered width. The nominal height of the resultant Arabic aleph and the English upper case letters should be 2800 millimeters. A TEXT SYMBOL message should be limited in length so that it can be centered between parallel longitudinal pavement markings, or such a marking and a curbline, with a minimum clearance on each side of 150 millimeters. When both Arabic and English messages are required the English should be placed above the Arabic (such that approaching drivers will see the Arabic message first). The separation between the Arabic and English text

6.8.2 TEXT SYMBOL MARKINGS 695 Markings 695 may be used to provide specific localized amplification of existing regulatory, warning, or guide road signs or pavement markings. TEXT SYMBOL markings 695 should be Abu Dhabi Municipality standard Arabic and English fonts. English text messages should use only upper case letters and, if appropriate, numbers. Stencils for text messages should be prepared based on 400millimeter “x” height letters on their tile back6-25

Version 0.1


Note: Delineators should be placed at a constant distance from the roadway edge except that, when an obstruction exists near the pavement edge, the line of delineators makes a smooth transition to the inside of the obstruction. Bridge rail or obstruction Type 2 object marker Edge of roadway

Guardrail

Edge of shoulder

0.6 m to 2.0 m outside shoulder edge 0.6 m to 2.0 m outside roadway edge or face of curb Typical spacing 60 m to 160 m

Figure 6-11 Typical Delineator Installation

Version 0.1

6-26

Delineators mounted above or immediately behind guardrail. These delineators are not at a constant distance from roadway edge because of the bridge rail.


will be achieved by stacking the distorted respective tiles.

6.9

Curbs at openings in a continuous median island need not be marked unless individual study indicates the need for this type of marking.

DELINEATION 6.9.4 DELINEATOR APPLICATION

6.9.1 DELINEATORS

Delineation is intended to be a guide to the vehicle operator as to the alignment of the highway. Whatever is needed to provide that guidance in a clear and simple way should be installed.

Road delineators are light-retroreflective devices mounted in series at the side of the roadway to indicate the roadway alignment. Delineators are effective aids for night driving and considered as guidance devices rather than warning devices. Delineators may be used on long, continuous sections of highway or through short stretches where there are changes in horizontal alignment, particularly where the alignment might be confusing or at pavement-width transitions. An important advantage of delineators in certain areas is that they remain visible when the roadway is wet.

The color of delineators should, in all cases, conform to the yellow or white color of edge lines. Single delineators should be provided on the right side of expressway roadways and on at least one side of interchange ramps. These delineators may be provided on other classes of roads. Single delineators may be provided on the left side of roadways and should be provided on the outside of bends on interchange ramps.

6.9.2 DESIGN

Where median crossovers are provided for official or emergency use on divided highways and these crossovers are to be marked, a double-yellow delineator should be placed on the left side of the through roadway on the far side of the crossover for each roadway.

Delineators should consist of reflector units capable of clearly reflecting light under normal atmospheric conditions from a distance of 300 meters when illuminated by the upper beam of standard automobile lights. Reflective elements for delineators should have a minimum area of approximately 100 cm². Double delineators consist of two reflector units, one mounted above the other. Elongated reflective units of appropriate size may be used in place of the two reflectors.

Red delineators may be used on the reverse side of any delineator whenever it would be viewed by a motorist traveling in the wrong direction on that particular ramp or roadway.

6.9.3 CURB MARKINGS FOR DELINEATION

Delineators of the appropriate color may be used to indicate the narrowing of a pavement. The delineators should be used adjacent to the lane affected for the full length of the convergence and should be so placed and spaced to show the width reduction. Delineation is not necessary for the traffic moving in the direction of a wider pavement or on the side of the roadway where the alignment is not affected by the convergence. On a highway with continuous delineation on either or both side, delineators should be carried through the transition and a closer spacing may be warranted.

Reflectorized, continuous yellow paint should be placed on the curbs of intersection islands located in the line of traffic flow where the curb serves to channel traffic to the right or to the left of the island. Reflectorized, continuous white paint should be used when traffic may pass on either side of the divisional island. Where the curbs of the islands become parallel to the direction of traffic flow it is not necessary to mark the curbs unless a study indicates the need for this type of delineation. Where these curbs are marked, the colors should conform to the general principles of pavement markings.

Delineation is optional on sections of roadway between interchanges where fixed-source lighting is in operation.

6-27

Version 0.1


6.9.5 DELINEATOR PLACEMENT AND SPACING

Table 6-5 Suggested Maximum Spacing for Highway Delineators on Bends Radius of Bend (R) Spacing on Bend (S) (meters) (meters) 15 6 30 7.5 45 9 10.5 60 75 12 90 13.5 16.5 120 150 19.5 180 21 210 22.5 240 24 25.5 270 300 27 Spacing for radii not shown may be interpolated from the table. The minimum spacing should be 6 meters. The spacing of the first delineator on a tangent adjacent to a bend should be 2S, the second, 3S, and the third 6S, but not to exceed 100 meters.

Delineators, if used, should be mounted on suitable supports so the top of the reflecting head is approximately 1.20 m above the near roadway edge. Delineators should be placed not less than 1.0 m or more than 2.0 m outside the outer edge of the shoulder, or if appropriate, in the line of the guardrail. Delineators may be mounted on the guardrail at a height less than 1.2 m. Delineators should be placed at a constant distance from the edge of the roadway. However, where a guardrail or other obstruction intrudes into the space between the pavement edge and the extension of the line of delineators, the delineators should be in line with or inside the innermost edge of the obstruction. Typical delineator installations are shown in Figure 6-11. Normally, delineators should be spaced 60 m to 160 m. When normal uniform spacing is interrupted by driveways, crossroads, or similar interruptions, delineators falling within such areas may be moved in either direction, a distance not exceeding one-quarter of the normal spacing. Delineators still falling within such areas should be eliminated. On expressways, a normal delineator spacing is 100 m.

devices may be used to mark any of the following type locations:

Double or vertically elongated delineators should be installed at 30-meter intervals along acceleration and deceleration lanes.

A typical barricade is illustrated in Figure 6-12.

Spacing should be adjusted on approaches and throughout horizontal bends so that several delineators are always visible to the driver. Table 6-5 shows suggested maximum spacing for delineators at bends.

Traffic cones and tubular markers are sometimes used outside of construction and maintenance areas for general traffic control purposes. Such uses include adding emphasis to channelizing lines or islands.

6.10 BARRICADES AND CHANNELIZING DEVICES

These devices should be a minimum of 450 mm in height and made of materials to withstand impact without damage to the devices or vehicles. Large-size devices should be used wherever more conspicuous guidance is needed.

1. Roadway ends in a dead end or cul-de-sac with no outlet. 2 A ramp or lane closed for operational purposes. 3. The permanent or semipermanent closure or termination of a roadway.

6.10.2 CHANNELIZING DEVICES

6.10.1 BARRICADES Red-and-white barricades are to warn and alert drivers of the terminus of a road, street, or highway in other than construction or maintenance areas. The stripes on the barricades should be reflectorized white and reflectorized red. These

Version 0.1

The color of cones and tube markers outside construction and maintenance areas should be the same as the pavement marking these devices are supplementing or substituting. These markers

6-28

200

150

1100 mm

200

150

200


150 mm

450 mm minimum

75 mm

100 mm

75 mm

75 mm

Barricade

Tubular Marker

Traffic Cone

Figure 6-12 Barricades and Channelizing Devices

6-29

Version 0.1


should be kept clean and bright for maximum target value. For nighttime use, the markers should be reflectorized.

Figure 6-14 illustrates curb painting and pavement markings for perpendicular, diagonal, and parallel parking spaces adjacent to fire hydrants.

Two typical channelizing devices (a tube and a cone) are illustrated in Figure 6-12.

Note that parking spaces need not be arranged to be centered on a fire hydrant and that the hydrant may be located anywhere within the curbed width or depth of the space. The parking space providing the best street visibility and access to the fire hydrant should be marked for no stopping. The fire-hydrant sign combination, however, should be placed in the center of the curbed width or length of the prohibited parking space.

6.11 CURB PAINTING AND PAVEMENT MARKING FOR FIRE HYDRANTS 6.11.1 CURB PAINTING FOR FIRE HYDRANTS ALONG ROADWAYS MARKING 695 Along roadways, curb painting is used in conjunction with NO STOPPING sign 370 and FIRE HYDRANT SUPPLEMENTARY PLATE 590 to reinforce to motorists the prohibition against stopping in front of a fire hydrant. In front of fire hydrants, curbstones should be painted red for a length of 12 meters, six meters to either side of the fire hydrant and the fire hydrant combination sign. Curb painting for fire hydrants along roadways is illustrated in Figure 6-13.

6.11.2 CURB PAINTING AND PAVEMENT MARKING FOR FIRE HYDRANTS ADJACENT TO PARKING SPACES Where a fire hydrant is located adjacent to a parking space, curb painting and pavement marking is used in conjunction with NO STOPPING sign 370 and FIRE HYDRANT SUPPLEMENTARY PLATE 590 to reinforce to motorists the prohibition against parking in that space. Curbstones should be painted red (marking 695) for the width (for perpendicular and diagonal parking) or length (for parallel parking) of the parking space. In addition, the parking space should be “closed” with a 100-millimeter-wide line across its entrance. Diagonal hatch markings, 100 millimeters wide, should run at one-meter intervals throughout the space.

Version 0.1

6-30


F. H. W. 14/1 NO. . .

Curb painted red

Standard curb painting

Standard curb painting 12000 mm

Figure 6-13 Curb Painting for Fire Hydrants Along Roadways Marking 695

6-31

Version 0.1


Sign 590 with NO STOPPING sign 370 Fire hydrant

Standard curb painting

1000 mm (typical) Curbstone painted red for one parking space only

45° (typical)

100 mm

100 mm 100 mm

Sign 590 with NO STOPPING sign 370

Curbstone painted red for one parking space only

45° (typical) 1000 mm (typical) 90° (typical)

100 mm

100 mm 100 mm

Curbstone painted red for one parking space only

Sign 590 with NO STOPPING sign 370

Fire hydrant

45° (typical)

100 mm 100 mm

100 mm

Figure 6-14 Curb Painting and Pavement Marking for Fire Hydrants Adjacent to Parking Spaces

Version 0.1

6-32


7 7.1

utility works with the safety of motorists, pedestrians, and workers foremost in their minds.

ROADWORKS TRAFFIC CONTROL

The same geometric and safety-design principles that apply to the design of permanent roadways should also govern the design of temporary traffic control situations. Temporary traffic control situations must not be allowed to be interpreted as being synonymous with substandard traffic control situations. If anything, the unusual and/or more restrictive conditions found in roadworks areas can dictate the necessity of even higher standards of safety. The aim should be to accommodate traffic in roadworks areas using geometric design considerations and traffic control devices comparable to those found in a normal permanent roadway operating at the speed anticipated in the roadworks zone.

GENERAL

Roadworks are defined as any roadway or utility construction, maintenance, or repair works occurring within or near a road right of way. Incident areas (traffic accidents, spillage, etc.), police-control points (check points, traffic surveys, etc.), and special-event management (major sports or cultural events) and other short-term disruptions to normal roadway operations also fit within the functional definition of roadworks traffic control. When approaching a roadworks area, motorists are faced with an unexpected, unusual, and frequently substandard driving situation. As a result, special care must be taken in implementing temporary traffic control measures in association with roadworks. Because roadworks are relatively short-term situations, traffic control in these areas is often given scant consideration. An unusual situation with an ill-conceived trafficcontrol scheme creates a doubly dangerous situation. Such would never be tolerated as part of the permanent operations nor should it be tolerated as part of the roadworks.

7.1.1.2

The standardization of devices is important for the purpose of advising motorists of conditions within a roadworks traffic control area. The color yellow has been designated as a unique color reserved for use in roadworks areas. All traffic control devices within a roadworks area should have yellow as their background color. Black and/or red border and/or symbols, in combination with yellow, should also be predominant work area colors. The uniform application of these colors on traffic control devices throughout a roadworks area will provide motorists with a visual indication that they are approaching and navigating a roadworks area where roadway conditions are not normal and that they should exercise additional caution.

7.1.1 BASIC PRINCIPLES The purpose of roadworks traffic control is to provide safe and effective work areas and to warn, control, protect, and guide vehicular and pedestrian traffic. To accomplish this, the respect of the driver must be earned by the appropriate, prudent, and consistent use of temporary traffic control devices. While each roadwork area may have unique elements, certain fundamental principles and procedures should be considered. 7.1.1.1

UNIFORMITY

Another aspect of uniformity is the standardization of the application of roadworks traffic control devices. Often, traffic control in a roadworks area is executed using traffic control devices that are substandard or nonstandard in material, design, or placement. Principles described throughout this manual with respect to permanent traffic signing are uniformly applicable to roadworks signing. Only devices described or permitted in this manual should be used for roadworks traffic control and they should be used in a uniform and standardized manner.

SAFETY

Traffic safety in a roadworks traffic control zone should be an integral and high-priority element of every roadway construction project from the design process until project construction is complete. Similarly, government and utility agencies must plan and conduct their maintenance and

7-1

Version 0.1


7.1.1.3

FUNCTIONALITY

When inconsistent markings are retained, extra attention must be given to ensure motorists can easily follow the detour geometry.

Traffic movements in a roadworks area should be inhibited as little as possible. Traffic control for a roadworks area should be designed acknowledging that motorists will reduce their speed only if they perceive a situation which warrants such. Therefore, reduced speed zones through a roadworks area should be avoided whenever practical, should be used only when dictated by geometric conditions, and should be applied with realistic speed limits.

7.1.1.4

Every work zone should be routinely inspected under varying traffic conditions and at different times of day to ensure that the traffic control devices are maintained so that they are clearly visible, properly located, clean and in good repair, and are operating safely and effectively. An important part of this inspection process must include the immediate removal or covering of any traffic control device which is no longer relevant.

Lane drops, lane narrowing, sharp curves, or other abrupt or frequent geometric changes should likewise be avoided. When such are unavoidable, adequate warning, delineation, and channelization by means of pavement markings, signing, and other devices must be used to effectively provide motorists with clear and positive guidance. These devices must be effective under the anticipated conditions of traffic volumes, traffic speeds, and lighting conditions. In turn, this requirement will have an effect on the geometric design, which must provide sufficient space for standard levels of temporary signing.

This level of control can best be achieved by assigning an authorized site safety officer to each work site. The site safety officer at small sites should automatically be the gang foreman. At all sites the site safety officer must be accountable for the original traffic management system and the maintenance of this system to ensure the safety of the workers, pedestrians, and the motoring public. The site safety officer must have the skill and authority to act to modify traffic control measures or even halt construction in order to ensure traffic and site safety. The site safety officer must keep a record of all accidents occurring at the site in sufficient detail to permit analysis to improve site traffic management.

To reduce complex traffic operational conditions to an acceptable level of simplicity, geometric changes should occur in individual stages, each of which requires only one basic driver action, with a stabilization area between each stage. For example, the closure of two lanes should be done in two individual transition areas. Likewise, a lane closure should not end and a sharp horizontal curve begin at the same point, but should be separated by a suitable stabilization area (see Section 7.1.2). However in exceptional circumstances a single taper as shown in Figure 8-24 (Chapter 8) may be used.

7.1.2 TRAFFIC CONTROL ZONE When traffic is affected by construction, maintenance, or utility operations, traffic control is needed to safely guide and protect motorists, pedestrians, and workers. Although individual roadwork areas may have unique features, most roadworks traffic control zones can be broken down and considered as five distinct areas. Each area has a unique and important function as part of a complete roadworks traffic control zone. Figure 7-1 illustrates these five parts of a roadworks traffic control zone.

A particular functional problem in roadworks areas is original pavement markings that conflict with revised detour geometry. Permanent pavement markings that are inconsistent with temporary travel paths and would misguide motorists should be removed on all but very short-term operations. For short-term operations, existing markings may be left in place unless so doing creates a definite hazard. No original pavement marking should be left in place that may tend to lead drivers straight into a barrier or work area. Version 0.1

MAINTENANCE

7-2


L

ZONE

ROADWORK

GUIDELINES

TERMINATION AREA

0.5L or less

WORK AREA

Varies

STABILIZATION AREA

0.5L to L (2L if separating transitions)

TRANSITION AREA

For S < 70 km/h L=DS²/160 For S > 70 km/h L=DS/1.6

ADVANCED WARNING AREA

100m to 2km

L = Length of Taper D = Displacement in meters

REPRESENTATIVE TAPER LENGTHS

S = Approach Speed in km/h = Direction of Travel

S

D

L

(km/h)

(meters)

(meters)

40 60 80 100

4.0 4.0 4.0 4.0

40 90 200 250

Figure 7-1 Roadworks Zone Traffic Control Areas

7-3

Version 0.1


7.1.2.1

• • •

ADVANCE WARNING AREA

This area is used to advise motorists that there are temporary conditions ahead of them that require particular care. In some instances, a stepped reduction in the speed will be required within this area. These speed reductions should be indicated at reasonable intervals (200 meters minimum) and occur in 20 kilometers per hour steps until the speed for which the traffic control has been designed is indicated. It is good practice to repeat the final speed limit at least once.

The transition area must be clearly defined using appropriate channelizing devices and should conform to the layout depicted on the guidance signs preceding it. Complex transition situations should be broken down into a number of standard transition situations. No signing for subsequent transition conditions should be included in a transition area, but rather should occur in the stabilization area separating the two transitions.

The length of the advance warning area should relate directly to measured approach speed. A realistic distance must be allowed for speed reduction. High traffic volumes will be better handled if the standard length of this area is generous, since more time is needed to comprehend the sign messages and react to them under heavy traffic conditions. For posted approach speeds of 100 kilometers per hour and moderately high to high traffic volumes, a base length for the advance warning area of 1000 meters is required. For freeway conditions, especially in rural areas, a length for the advance warning area of 2000 meters is preferred. If traffic volumes are low and/or posted approach speed is 80 kilometers per hour or less, this length may be reduced to 600 meters.

The length of a transition area will depend on the approach speed of traffic and the amount of alignment shift involved in the transition. Minimum lengths should be determined by the following formula: Minimum lengths should be determined by the following formula: L= DS²/160 for S < 70 km/h L= DS/1.6 for S > 70 km/h L= Minimum required length of transition in meters. D= Required lateral displacement of vehicles in meters. S= Approach speed of vehicles to the roadworks area traffic control zone in kilometers per hour (posted speed limit or 85th percentile speed whichever is greater).

Urban sites will commonly have limited space for advance warning area signs. However, every attempt should be made to provide adequate advance signing. High-speed arterials should normally have sufficiently long block lengths to allow advance warning areas in the range of 600 to 300 meters. On lesser roads or in busy business areas, shorter advance warning areas in the range of 150 to 75 meters should be used. Consideration should also be given to extending lane closures and the relevant signing into the preceding block and onto intersecting roads, as applicable. 7.1.2.2

The alignment of the transition area should be either a straight taper (in the case of a lane drop) or a reverse curve (in the case of an alignment shift). 7.1.2.3

Shift position on the roadway without reduction in the number of lanes.

Version 0.1

STABILIZATION AREA

The purpose of this area is to allow traffic flow to stabilize after negotiating a transition area before reaching another change of condition or the work area. If more than one transition area is required to achieve the final traffic configuration, the signing for the second or subsequent transitions should be located within the intervening stabi-

TRANSITION AREA

This is the area in which drivers are required to take action, such as: •

Merge two lanes into one (lane drop). Cross the central median (crossover). Enter a detour completely separate from the road under construction.

7-4


lization area(s). When the stabilization area occurs between a transition area and the work area the stabilization area will also serve as a buffer between the inherently dangerous work area and the transition area where loss of vehicular control is most likely. The buffer space provides a margin of safety for both traffic and workers. If a driver does not see the advance warning or fails to negotiate the transition, a buffer space provides room to stop before the work area. It is important that the buffer space be free of equipment, workers, materials, and workers' vehicles.

This should follow the same principles given for a transition area at the start of a site. End roadworks signs and conventional speed limit signs restoring the normal speed limit conditions should be erected together as soon as possible after the end of the termination area.

7.1.3 DEPLOYING ROADWORKS DEVICES One of the most critical periods during the life of a roadworks operation is the initial deployment of the roadworks traffic control devices. The steps listed below should be followed in the deployment of traffic control devices at roadworks:

When a stabilization area separates two transition areas, the length of the stabilization area should be double the length of the longer of the two transition areas being separated. When a stabilization area separates a transition area from the work area, the length of the stabilization area should be not less than one half the length of the preceding transition area, and preferably equal to the length of the preceding transition area when space permits. 7.1.2.4

1. A traffic control plan, with a level of detail appropriate for the complexity of the work involved, should be prepared, approved, and understood by all parties responsible for the roadworks on site. 2. All necessary traffic control devices and appurtenances identified in the traffic control plan should be procured and assembled on site prior to deployment. 3. All traffic control devices that can be installed without interference with existing traffic operations should be deployed. Signs erected that are not yet applicable, but that may be seen by drivers on roadways currently in use, should be covered to prevent confusion. 4. The deployment of the remaining traffic control devices, which will result in a diversion of traffic from current travel paths, should be done during hours of low traffic volumes. For major roadways this may require a latenight deployment. 5. Deployment should begin at the upstream end of the advance warning area with advance warning signs being uncovered or erected progressively towards the transition area. Next, channelizing devices, signs, and other traffic control measures should be deployed from the start of the transition area progressively to the stabilization area, through the work area and on to the end of the termination area. To the maximum extent possible, workmen and equipment should

WORK AREA

The work area is that portion of the roadway which contains the work activity and is closed to traffic and set aside for exclusive use by workers, equipment, and construction materials. Work areas may remain in fixed locations or may move as work progresses. This area must be adequately defined by delineators in complex conditions. Where there is a risk to traffic or workers of vehicles entering the work area, temporary barriers of a standard sufficient to prevent this are recommended to contain traffic within the designated roadway. When traffic is relocated well away from the work area little action is required along its length other than to protect construction vehicles and employees. 7.1.2.5

TERMINATION AREA

This area involves the return of traffic flow to normal flow conditions. In simple cases this can be achieved by a relatively rapid taper of channelizing devices. In this case, the length of the termination area may be one-half of the computed transition area length or less. In more complex conditions a reverse crossover may be required. 7-5

Version 0.1


remain on the back side (away from the traffic) of channelization devices during deployment. 6. Conflicting existing signs should be removed or covered. 7. Conflicting existing pavement markings should be removed and new temporary markings installed (if conditions warrant, "stick down" type temporary markings may be required until the more permanent temporary marking can be installed under traffic). 8. Following completion of deployment the roadworks zone should be immediately inspected by the site safety officer with any misplaced devices or confusing situation corrected. A careful monitoring of the roadworks zone by the site safety officer, especially for the first few days of operation, is essential to detect and correct any difficulties experienced by drivers at various times of the day or night and under varying traffic conditions.

such a diversion, the signs must conform to the exclusive temporary color code reserved for roadworks signing and be positioned as indicated in this chapter. The following sections do not deal with individual sign types unless the only application of a specific sign is in a roadworks situation (e.g., advance warning ROADWORKS sign 7441). The significance of a roadworks version of a normal sign remains the same as indicated in Chapters 3, 4 and 5. The signs are, however, illustrated in Figures 7-2 to 7-5 in their appropriate colors for use at roadworks. For roadworks signs based on a normal, nonroadworks sign, the number "7" is added before the normal sign's number to indicate the roadworks version of the sign. For example, sign 346 prohibits left turns in a normal situation. Its roadworks counterpart, sign 7346, prohibits left turns in a roadworks situation. In this example, only the background color of the sign changes.

The removal of roadworks zone traffic control devices should occur in generally the reverse order of deployment, beginning at the termination area and working back through the advance warning area. Roadworks devices no longer needed should be removed completely from the roadway and inapplicable roadworks signs removed or covered. Conflicting temporary pavement markings should be removed from the permanent roadways.

7.2

7.2.2 REGULATORY SIGNS All subclasses of regulatory signs may be used at roadworks sites. 7.2.2.1

Control signs commonly used at roadworks comprise: • • • • •

TRAFFIC SIGNS

7.2.1 GENERAL Regulatory, warning, and guidance traffic signs comprise a major part of the temporary traffic control devices used at roadworks sites.

STOP sign 301. GIVE WAY sign 302. GIVE WAY TO PEDESTRIANS sign 303. NO ENTRY sign 304. ONE WAY TRAFFIC signs 305, 306 and 307.

Any of these signs may be used at roadworks and when used should retain their normal colors as specified for permanent applications.

If a traffic diversion is constructed fully in all respects to normal geometric standards, normal regulatory, warning, and guidance signs may be specified for the diversion. However, even in such circumstances of geometric design it may be considered beneficial to use roadworks signs just to make drivers aware that the conditions are temporary. If any of the geometric or other design parameters are below normal standards within

Version 0.1

CONTROL SIGNS

STOP-SLOW SIGN 7308 Sign 7308 is a special variation of STOP sign 301. At roadworks sites it can be used to control alternating one-way streams of traffic through a restricted part of the roadworks site. A pair of

7-6


Roadworks Control Signs

301

302

304 303

305

306

307

7308

Roadworks Mandatory Signs

7321

7322

7323

7324

7325

7326

7327

7328

7329 Roadworks Prohibition Signs

7339

7340

7341

7342

7343

344

7346

7347

7348

7349

7350

7351

7352

7353

7354

7355

7356

7365 Roadworks Freeway Control Sign

Roadworks Parking Control Signs

7371-7373

7374-7376

7377-7379

7380-7382 Figure 7-2 Regulatory Signs at Roadworks

7-7

7399

Version 0.1


Roadworks Advance Warning Signs (not all signs shown)

7401

7402

7403

7407

7408

7409

7411

7412

7413

7414

7415

7416

7417

7418

7419

7420

7421

7422

7423

7424

7425

7427

7428

7429

7430

7435

7441

7442

7443

7450

Roadworks Hazard Marker Signs and Devices

7451

7452

7458

7454

7455

7460

7456

7459

Figure 7-3 Warning Signs at Roadworks

Version 0.1

7-8

7457

7461


Roadworks Traffic Movement Affected by Obstruction Signs

7465

7473

7466

7467

7468

7469

7474

7475

7476

7477

7481

7482

7483

7470

7472

7478

Roadworks — Additional Lane Signs

7479

7480

Roadworks — Lane Control Signs

7484

7485

7486

Roadworks — Lane Merge Signs

7490

7491

7492

Figure 7-4 Diagrammatic Signs at Roadworks

7-9

Version 0.1


Roadworks Route Marker and Trailblazer Signs

7501

7503

7505

7508

Roadworks Direction Signs

7512 At-Grade Vertical Stack Sign (single)

7515 Chevron Detour Sign

7589 Supplemental Plate

7512 At-Grade Vertical Stack Sign

Figure 7-5 Guide Signs at Roadworks

Version 0.1

7-10


The following prohibitory sign is not appropriate to a normal or "permanent" application and is to be used exclusively for roadworks situations: MAXIMUM WIDTH LIMIT SIGN 7356 Sign 7356 requires that drivers of vehicles exceeding the indicated width should not proceed beyond the sign.

Sign 7308

flagmen may control traffic movement by alternately stopping and releasing traffic in opposing directions using the STOP sign as a hand-held "paddle" on which the reverse side indicates the message "SLOW" in black on a yellow background. Sign 7308, when displaying the STOP face, requires that a driver of a vehicle should stop such vehicle at the point indicated by the flagmen, AND, when displaying the SLOW face, requires that a driver of a vehicle should proceed slowly through the restricted work area until advised otherwise by an appropriate road sign. 7.2.2.2

Sign 7356

MANDATORY SIGNS MAXIMUM WIDTH LIMIT sign 7356 should be located 25 to 50 meters in advance of the limited-width structure, preferably on both the right and left sides of the approach roadway. The width indicated within the sign should be at least 200 millimeters less than the minimum width measured at the structure. The width should be expressed on the sign to the next lowest one-decimal place of a meter.

All signs in this group may be used at roadworks sites, although TURN RIGHT (or LEFT) AHEAD ONLY sign 7324 (or 7325) and PASS EITHER SIDE sign 7326 are unlikely to be used. When used at roadworks the signs in this group should have a black on yellow color code so that the arrow and border are black on a yellow background. It should be noted that the black border is set in from the outer edge of the sign to leave a thin outer yellow border. 7.2.2.3

7.2.2.4

PARKING CONTROL SIGNS

Temporary prohibitory NO STOPPING signs 7371 to 7376 and NO PARKING signs 7377 to 7382 in their various forms may be used at roadworks or building construction sites in their temporary form using a yellow background. When such roadworks signs are used any conflicting permanent prohibitory or permissive parking sign which is in position on the section of road should be covered or temporarily removed. The use of temporary roadworks permissive parking signs is unlikely to be warranted. It is more practical, when necessary, to modify the scope and extent of existing permissive parking signs and to simply reposition these or to provide new signs.

PROHIBITORY SIGNS

All signs in this group may be used at roadworks sites. The signs retain their red border, and slash where appropriate, and black symbols, but the background color should be yellow. The use of the roadworks version of NO OVERTAKING sign 7349 will be particularly relevant on two-lane, two-way roads during the period when a new section of road has been surfaced but pavement markings are not yet in place.

7-11

Version 0.1


7.2.2.5

7.2.3 WARNING SIGNS

FREEWAY CONTROL SIGNS

END OF FREEWAY sign 7399 may be used, if required, in a black on yellow form when roadworks on a freeway are such that the freeway can no longer operate to the accepted standards of a freeway.

All types of warning signs are particularly appropriate in a roadworks environment, from the most minor maintenance operation to the construction of a new road or the rehabilitation of a freeway. The majority of signs covered in Chapter 4 may be used in a temporary capacity with a yellow background. The most common of these are illustrated in Figures 7-3 and 7-4. The meaning of the various roadworks signs remains as stated in Chapter 4 although their positional application may vary from that for normal warning signs. A number of signs which are appropriate to use at roadworks only, and therefore to manufacture in the black on yellow color code only, are covered in detail in the following sections. 7.2.3.1

ADVANCE WARNING SIGNS

Virtually all advance warning signs may be used in a roadworks form. The most likely ones are illustrated in Figure 7-3. The following advance warning signs are, however, unique to roadworks and not appropriate to a normal or "permanent" application.

Sign 7399

BEGINNING OF FREEWAY sign 398 should not be used in a temporary roadworks form. When a freeway has temporarily been downgraded during roadworks, a normal BEGINNING OF FREEWAY sign 398 should be located beyond the end of the work area to indicate a return to normal freeway operation.

ROADWORKS SIGN 7441 Sign 7441 warns drivers of vehicles that there are roadworks ahead and that they should prepare to

Sign 7441

Version 0.1

7-12


reduce speed and/or proceed with caution through the work area and its approaches.

On the basis that it is commonly used as the first sign, or pair of signs, in a sequence of roadworks signs, sign 7441 should be located at a distance from the start of any change in traffic conditions resulting from roadworks, as indicated in Table 7-1. A clear sight distance should be maintained to the sign whenever possible.

ROADWORKS sign 7441 is the universal warning sign for all levels of roadworks. It should be carried by every municipal, service agency, or contractor's gang. Sign 7441 may also be displayed within a high-visibility background as the first advance warning sign in a sequence of roadworks signs preceding a major work site or detour around such a site (i.e., at the start of an advance warning area). In all situations except the most minor work site, sign 7441 should be used in conjunction with a SUPPLEMENTARY PLATE sign 7589 mounted below the sign displaying the distance to the site.

When the approach speed to a roadworks site is over 60 km/h, sign 7441 should be placed on both the right and left side of the carriageway on dualcarriageway roads. At a major roadworks site, ROADWORKS sign 7441 may be used more than once in a sequence of signs within an advance warning area and it may be used locally to specifically warn of the presence of workers close to the roadway within

Table 7-1 Location of Roadworks Sign 7441 Approach Speed Required Speed Distance Of (First) Typical Roadworks (85th percentile) Reduction Sign 7441 From Start (1) Condition (km/h) (km/h) (meters) 1000 minimum 20 100 or more 2000 minimum 40 or more 1000 preferred 1. Lane drop/deviation/major 80 20 or more 600 minimum works 600 preferred 60 20(2) 300 minimum 600-300 100 (3) 2. Maintenance work off roadway 200-100 60 (3) 600-300 100 20 3. Maintenance work on shoulder 300-200 60 (3) 800 20 100 4. Mobile maintenance (with 1000 40 adjustment if work requires a 600 20 similar treatment to item 1) (4) 60 600 40 600 minimum 5. Temporary traffic signal or 100 100 200-150 “STOP-SLOW” control 60 60 100 preferred 6. Community environment, local 60-30 minimum road narrowing, or service 40-60 20 work NOTES: 1. The “start” of the roadworks site means the point where a transition area begins, or if one is not used, where the work area commences. 2. If the work situation is within a community the requirements given in item 6 may be considered more appropriate. 3. The driver reaction required is one of “caution” and a preparedness to slow down if necessary, rather than an immediate speed reduction. 4. Mobile maintenance operations require considerable care in the management of approaching traffic. Lane drops or detours may prove essential to safe operation. The advance sign(s) for a mobile operation should move with the work so that they are never more than 2000 meters in advance of the work.

7-13

Version 0.1


a roadworks zone. It is recommended that sign 7441 also be used at the end of a construction site when traffic is returned to normal conditions, as a courtesy to drivers, with a SUPPLEMENTARY PLATE sign 7589 mounted below the sign displaying the message "END" in Arabic and in English. Sign 7441 should be pole mounted for all installations covered by Table 7-1 or similar situations, with the exception of very short term or mobile work when the sign may be mounted on a movable stand. Sign 7443

FLAGMAN AHEAD SIGN 7442 7.2.3.2

Sign 7442 warns road users that there is a flagman ahead and they should take note of his signals and be prepared to reduce speed or stop if required to do so.

HAZARD MARKER SIGNS

In a similar way to the normal applications of hazard marker signs, temporary versions of the signs should be used extensively in roadworks areas to warn road users of the specific position of hazardous obstructions. The signs are illustrated in Figure 7-3. HAZARD PLATE signs 7451 and 7452 and SINGLE CHEVRON signs 7454 and 7455 may both be used in addition to, or in place of, traffic cones to delineate curves and tapers within a roadworks zone. For such an application the signs and their support materials should be manufactured from plastic or similar deformable materials which are suitable for the application of retroreflective materials (see Section 7.3.5). 7.2.3.3

Sign 7442

This class of warning sign has great potential to assist drivers to negotiate roadworks sites safely. In general they are recommended for use in advance of the start of a transition area in conjunction with appropriate SUPPLEMENTARY PLATE sign 7589. It is also recommended practice to locate signs on both sides of a roadway and, in addition, to repeat this treatment approximately 200 meters closer to the transition area. In this way drivers are given a pictorial representation of the approaching change in circumstances up to four times before they actually reach the point of change.

FLAGMAN AHEAD sign 7442 may be used in very short-term situations (e.g., at an accident site within a roadworks zone) or in more permanent conditions where the hazard is particularly severe or for traffic control purposes (see Section 7.4). A SUPPLEMENTARY PLATE sign 7589 indicating the distance to the flagman should be mounted below the sign. The sign should be located on the right side of the roadway at a distance from the flagman as indicated in Table 4-1 and with a clear sight distance. Sign 7443 may be used in place of sign 7442 when appropriate.

Version 0.1

DIAGRAMMATIC WARNING SIGNS

7-14


Typical of the conditions which occur at roadworks sites and which may be depicted on temporary diagrammatic warning signs are:

A SUPPLEMENTARY PLATE sign 7589 indicating the distance to the median detour may be mounted below the sign.

•

REDUCED WIDTH OF ROADWAY SIGNS 7474 TO 7478

• • • • • •

Lane drops or closures (only ONE lane drop per transition area or per sign). Diversions through a median island or onto a service road or separately constructed detour road. Pavement narrowing. An indication of additional lanes ahead in order to reduce the risk of impatient drivers overtaking too soon in an unsafe manner. Additional lanes where these may not be expected and may result in increased traffic friction. Lane use control by goods vehicles within roadworks. Lane merging conditions.

Sign 7474

Signs appropriate to many of these conditions are described in Chapter 4. The following signs are additional examples which are appropriate to use at roadworks.

Sign 7475

Signs 7474 to 7478 warn drivers of vehicles that the roadway they are traveling on is reduced in width over a considerable distance and is bordered by a barrier or excavation.

MEDIAN DETOUR SIGNS 7467 TO 7470 REDUCED WIDTH OF ROADWAY signs 7474 to 7478 may be warranted and used under similar conditions to those stated for signs 465 and 466 in Chapter 4.

Signs 7467 to 7470 warn drivers of vehicles that the roadway they are traveling on will detour through a median or barrier, executing a reverse curve in the process.

A SUPPLEMENTARY PLATE sign 7589 indicating the distance over which the hazard exists may be mounted below the sign. A representative selection of temporary diagrammatic warning signs is illustrated in Figure 7-4. When a new concept is considered for a sign face design, care must be exercised to adhere to the standard design criteria given in Chapter 4. Alternative diagrammatic warning sign face designs must be approved by the Department prior to implementation. Sign 7469

Sign 7470

Throughout the text of this section references have been made to the use of SUPPLEMENTARY PLATE sign 7589. These signs are purely information signs without a specific regulatory, warning or guidance function. They should, therefore, not be used on their own. Their function is to clarify the point to which a regulatory or warning sign applies (distance "to" or distance

MEDIAN DETOUR signs 7467 to 7470 may be warranted and used under similar conditions to those stated for signs 465 and 466 in Chapter 4.

7-15

Version 0.1


"for") or the degree of severity of the hazard (advisory speed) or to give other general information (end).

to be reused many times when they have to be repositioned, simply by changing the supplementary plates.

Because regulatory sign messages normally apply from the point at which the sign is placed, the use of SUPPLEMENTARY PLATE sign 7589 with regulatory signs is relatively infrequent. It is also a basic principle governing the use of regulatory signs that they should not normally be used to "warn" of a regulation coming into force up ahead. While this principle should also apply to roadworks the likelihood that it may be necessary to apply the principle with discretion is greater as a result of roadworks. When the need to indicate the existence of a regulation ahead arises, and this requires some action by drivers before reaching the point of its application, it is recommended that a custom-designed sign be used rather than a supplementary plate. This should generally be a map or pictorial sign and may include a regulatory sign.

7.2.4 GUIDE SIGNS Amended guide signs indicating destination names are only likely to be required at major roadworks or where a diversion or detour is in place as a result of roadworks. In the simplest of cases, where the detour leads without any risk of misdirection back onto the original road, CHEVRON DIRECTION sign 7515 may be used. These signs should display the word "Detour" in Arabic and English. Sign 7515 may be positioned strategically through the detour, pointing to the right or left as appropriate, as the detour changes direction. It will therefore commonly supplement roadworks cones, delineators, or SINGLE CHEVRON signs 7454 and 7455. In such instances, advance signing using appropriate diagrammatic warning signs, without destination names, is likely to be adequate.

In a roadworks environment SUPPLEMENTARY PLATE sign 7589 should be used with the majority of warning signs to enhance the clarity of their message for the following reasons: • •

•

When a diversion or detour is such that drivers may be confused as to which direction to take in order to reach their intended destination, existing direction signs should be amended or replaced to convey the correct messages. Under such circumstances, when an existing sign still remains correct in part, the alterations should be indicated either:

The visual clutter of roadworks sites makes it otherwise difficult to correlate the sign with the situation ahead of which it is warning. Drivers are commonly subjected to more frequent messages affecting the driving task (not only from road signs) that may affect their ability to judge conditions accurately. When used on successive signs in a sequence of signs to give drivers a sense of rate of progress or a "countdown" into the site.

•

• SUPPLEMENTARY PLATE sign 7589 is not appropriate with hazard-marker warning signs, only with signs used in advance of a hazard such as advance warning signs or diagrammatic warning signs placed in advance of the conditions to which they apply.

If the route is altered to the extent that most or all of the directions on the sign are altered in some way, it is recommended that a new sign be used in advance of the junction in accordance with the positioning criteria given in Chapter 5. If there is any doubt about the geometric standard of the detour or if the destinations are substantially rearranged, a new sign should be erected with a

It is generally recommended that supplementary plates for use with roadworks signs not be manufactured in one piece with the relevant sign but are manufactured as separate signs and attached to the same support as the sign they are supplementing. This will allow the larger warning signs Version 0.1

By overlaying the altered destination message with the correct one using a temporary plate with a yellow background and black lettering, or By covering the incorrect message and erecting a separate additional temporary sign indicating the appropriate revised direction in black legend on a yellow background.

7-16


yellow background and black letters, arrows, and borders. Otherwise existing direction signs may be retained. However, the mixed use of typical guide signs and roadworks guide signs throughout the length of a detour may be confusing or disorienting for drivers. If a detour is to be in place for some time or if a detour is long, typical guide signs should be replaced by roadworks guide signs throughout the length of the detour, regardless of whether the typical guide signs offer accurate guidance and information.

they are impacted by a vehicle the damage to the vehicle is limited and the risk of injury to workers is minimized. Many of the channelization devices listed above are used in multiples at regularly spaced intervals. When the construction project is of even a few hours duration the devices are likely to be disturbed from their original alignment due to being struck, due to construction activities, and commonly as a result of the air displacement of passing vehicles. Under such circumstances they will quickly cease to perform their intended collective function of providing alignment guidance. Sections of channelization devices must therefore be regularly patrolled and "repaired" either by repositioning of devices or by replacement if the devices are no longer capable of achieving their individual function.

In order to reduce costs of such relatively large temporary direction signs to more acceptable limits, the information displayed for temporary direction may be limited to the display of the route number shields only on temporary route marker signs and temporary trailblazer signs (see Figure 7-5).

7.3

CHANNELIZATION DEVICES

When setting out a medium- to long-term section of channelization it is a recommended practice that the required positions of movable channelization devices be marked on the road surface using small paint marks. This will enable devices to be repositioned or replaced with a minimum effort and with minimum exposure of workers to the hazards of passing traffic. This same spot marking technique may be used for maintenance operations, which will go on for several days, but which are put in place every morning and removed every evening.

7.3.1 GENERAL Channelization devices are elements of the total system of traffic control devices used at roadworks sites to provide the safest possible environment for road users and workers. The function of channelization devices is to alert road users to alterations in the roadway alignment or width resulting from construction activities. Their use is particularly relevant when such changes in alignment create hazardous or potentially hazardous circumstances for road users.

7.3.2 PAVEMENT MARKINGS Pavement markings comprise two specific types of channelization device, namely:

Channelization devices should be used within transition areas, stabilization areas, work zones and termination areas (see Figure 7-1). They should be placed so as to provide a smooth and gradual change of alignment or width of roadway. They may also be used in small numbers on a very localized basis at small maintenance work sites.

• •

Flush markings normally applied in the form of paint or thermoplastic materials, or Raised markings.

There are two main factors related to pavement marking that are relevant to their use within roadworks sites:

The range of channelization devices available includes, but is not limited to, pavement markings, cones, drums, barriers, barricades, delineators, and other individual illumination devices. All vertically positioned channelization devices should be constructed so that in the event that

• •

7-17

The need to maintain, modify, or remove existing pavement markings during the roadworks period, and The need for additional temporary pavement markings as part of the channelization treat-

Version 0.1


ment required to control the use of a roadworks site.

way alignment involving traffic shifts within roadworks should not be undertaken if site resources, in terms of manpower and/or equipment, are not available to achieve a safe and effective result.

The effect of both of these factors is very much dependent on the duration of the work to be undertaken. Due to the relative difficulty of removing and applying pavement markings, particularly when traffic still occupies the section of road, short-term modification may be costly to achieve. This factor must be born in mind at the time that roadworks traffic control plans are being prepared so that the need to remove and apply temporary pavement markings is minimized. 7.3.2.1

Irrespective of the duration of the work, such inspections should take particular note of pavement markings which might inadvertently lead drivers away from the intended path. If a barrier or barricade is placed across any lane line or centerline marking in such a way that any lane leads straight into the barrier, steps must be taken immediately to remove this visual hazard. For short-term situations the relevant sections of road marking should be obliterated by using black, textured, pressure-sensitive tape. This tape can be applied simply and quickly and can normally be removed with little difficulty. This action should be taken under appropriate circumstances even for work which will only last for four to eight hours. When a lane is temporarily closed to traffic the same technique should be adapted so that the lane line markings are hidden over the full length of the tapering section. The only acceptable alternative action is to use flagmen to warn and control approaching traffic, but if work is not completed by nightfall, attention must be paid to this hazardous aspect of the existing markings.

PAINTED MARKINGS

In terms of color, shape, and dimensions there are no differences between permanent and temporary pavement markings. The enhanced line-to-gap ratio of broken line markings may be used to improve the visual effect of temporary pavement markings, particularly when these are used with reduced geometric standards(see Chapter 6 for details). Painted pavement markings have the limitation that they may be obliterated or rendered ineffective very easily due to: • • • •

Heavy traffic volumes. Resurfacing operations on an adjacent section of road. Wind-born dust and debris. Adverse weather conditions.

There is otherwise likely to be little need for temporary painted markings at short-term work sites of up to 72 hours duration. In such circumstances adequate delineation can be achieved using other channelizing devices to indicate modified vehicle paths.

Insofar as painted markings may be affected, short-term work is likely to be unplanned or reactive (e.g., a localized and urgent need to repair a service or some similar circumstance). In contrast, medium- to long-term work should involve some degree of planning for pavement marking.

Subject to the ease with which paint marking equipment may be used within a detour, longer tasks lasting up to two weeks may be marked, when necessary, using similar white pressuresensitive marking tapes. (Where two-way traffic is in operation, yellow pressure-sensitive marking tapes should be used.) For tasks of this duration it will not normally be necessary to mark or remark edge lines.

When construction or maintenance work lasting more than one work shift necessitates modified vehicle paths through the work site, day and night drive-through checks should be made by the work supervisor or site safety officer to evaluate the safety and effectiveness of the revised or temporary pavement markings. This drivethrough inspection should occur, if at all possible, before any new section of a detour or a modified roadway is opened to traffic. Revisions to roadVersion 0.1

For planned work that is expected to last more than two weeks, painted markings on the various temporary alignments should be applied using conventional equipment. Any redundant painted markings must also be removed at this time, 7-18


preferably by using high-pressure water blasting. This treatment leaves a minimum of pavement scars and completely removes old markings. Blacking out existing markings or using harsher removal techniques is not recommended as these methods leave residual lines that, under adverse light conditions, can appear as clearly as a painted marking, resulting in significant confusion for drivers. If removal methods such as sand-blasting are used, care should be taken to avoid leaving these residual or phantom lines.

markings subject to the same rules regarding color and spacing as are given for permanent applications in Chapter 6. Permanent and temporary raised pavement markers may be used to provide an audible warning to drivers that they are straying off the intended vehicle path. This application may often be warranted at roadworks due to the common use of reduced geometric standards. In such circumstances raised pavement marker spacing should be reduced over short localized distances if appropriate. Permanent and temporary raised pavement markers may also be used to increase the visibility of longitudinal pavement markings and thereby their alignment and the visibility of gore areas when roadways split.

The planning of medium- to long-term work, which will require regular and significant alterations to pavement markings, must take specific account of the need to mark, remove, and remark lines on a regular basis over a common section of roadway. Minimizing this aspect of the work should be an integral part of the preparation of the roadworks traffic control plans. The following factors should be given consideration: • • •

Temporary raised pavement markings may be used to completely replace longitudinal paint markings when the latter will be subject to considerable wear and it will be difficult to regularly maintain them. Raised pavement markers used in this manner can also be very effective in keeping vehicles in their own lanes (raised pavement markers should therefore not be used over sections of detour where merging or weaving movements are required). When used in this manner raised pavement markers should be spaced at approximately one meter centers so that four raised pavement markers will replace a three meter paint marking.

The use of short-life paint, which will not require much removal effort (e.g., a waterbased paint). The use of pressure-sensitive tapes. The use of removable raised pavement markers (see Section 7.3.2.2).

The above factors are also relevant when paint markings are temporarily required on intermediate surfacing levels during phases of construction.

Temporary raised pavement markers should be applied to the road surface using an approved non-hardening adhesive mastic to permit their removal for realignment and/or re-use as necessary. The approved adhesive must not only permit such removal but must also resist movement under vehicle impact.

When a road construction project is complete and ready for opening to traffic, all road markings must be in place in accordance with the roadmarking design and the provisions of Chapter 6 before the road is opened. 7.3.2.2

RAISED PAVEMENT MARKERS

7.3.3 CONES Raised pavement markers used for temporary applications have the same functions as permanent markers, namely: • • •

Traffic cones are a very visible type of traffic control device used for channelization purposes. They have the capability to be deployed quickly in emergency situations, a worker can carry several at a time with ease and they can be stored in a compact manner. When used at close spacings they can effectively delineate any type of temporary alignment within a roadworks site.

To supplement other markings. As vehicle positioning guides. As a substitute for other markings.

Raised pavement markers may be used as a form of temporary marking to supplement painted 7-19

Version 0.1


7.3.3.1

•

TRAFFIC CONE DEVICE 7459

•

Traffic device 7459 is a nondirectional device which, by virtue of the number used at closely spaced centers, warns road users of a short-term realignment of a lane or roadway.

•

The color of all cones should be fluorescent red or red-orange. The base should be sufficiently heavy to ballast the cone to withstand air buffeting from vehicles passing at 60 km/h (the base may be designed to accept additional ballast such as sandbags provided this is designed in such a way that it does not create any additional hazard). Any cone used during the hours of twilight, darkness and/or dawn should be fitted with a yellow sleeve of retroreflective material so that this sleeve occupies approximately the middle third of the height of the cone. This sleeve should have a smooth sealed outer surface and should have the same effective color by day and by night.

7.3.3.3

TRAFFIC CONES control device 7459 should be the primary channelization device used to define roadway alignment in the form of:

Device 7459

7.3.3.2

CONE DESIGN PARAMETERS

TRAFFIC CONES device 7459 should conform to the following design requirements:

• • •

•

•

• • • •

They should be conical in shape and manufactured from a material capable of withstanding many impacts without sustaining damage and without risk of damage to vehicles or injury to workers. They should have a hollow construction and be capable of being stacked one inside the other to fit into compact spaces. The minimum height for use at minor works and emergency or accident sites should be 450 millimeters. The minimum height for use on arterial roads and freeways should be 750 millimeters and 1000 millimeters respectively. The nominal diameter of the cones at their base should be:

• •

Tapers, including lane drops. Sharp curves. Reverse curves, including median crossovers. Reduced roadway width adjacent to the work site. Traffic islands, including traffic circles. Localized hazard marking particularly at minor work sites.

The traffic cones may be placed on one side or both sides of a roadway. Table 7-2 gives the recommended spacing between cones for various applications. Cone spacing may be reduced if necessary to improve visual effectiveness of temporary roadway alignments. Cone spacing should be set at 6 meters when the work area is 200 meters or less in length. Cone spacings in excess of 50 meters will permit drivers to easily enter a work area and are not recommended. Spacings set in the upper range may be reduced around curves with a radius in the range of 300 meters to 600 meters.

- 250 millimeters for a height of 450 millimeters. - 400 millimeters for a height of 750 millimeters. - 500 millimeters for a height of 1000 millimeters.

Version 0.1

CONE APPLICATIONS

When cones are also intended to provide a visual restriction or channelization of pedestrian movement, 1000-millimeter-high cones should be used 7-20


Table 7-2 Recommended Cone Spacings Center-to-Center Cone Spacing (meters)

Temporary Condition Transition Area Taper 1 in 10 or less 1 in 20 1 in 30 1 in 40 or more Transition Area Crossover curve radius under 60 meters curve radius over 60 meters Stabilization or Work Area (assumed to be straight) Long Straight Work Areas (including maintenance work areas) Localized Minor Work Area

and placed at two-meter maximum spacing. Such cones should be physically interconnected by either a purpose-made, rigid barricade panel or by nylon rope with yellow and red strips of plastic warning tape — "tiger tape" — securely fixed at third points between.

2 4 6 8 1 2-4 6-20 20-50 1-2

way or from entering an area closed for roadworks or other special operations. Barricades are temporary portable devices used to demarcate areas that are not open to traffic in the form of vehicles or pedestrians. Such areas commonly include the stabilization area (or buffer zone) in advance of a work area or localized minor excavations.

Precautions must be taken to ensure that cones remain in their intended position both from a safety and from a site efficiency and effectiveness point of view. For long-term installations bases may be fixed to the road surface with an approved nonhardening removable adhesive. When a more adjustable installation is required, the base of the cone must be ballasted sufficiently to resist the buffeting caused by passing vehicles.

7.3.4.1

BARRICADE DEVICE 7460

Traffic device 7460 is a nondirectional barricade which warns road users, both pedestrians and drivers, of a hazard in their path beyond which they should not proceed. The device may be used to demarcate work areas, including footpaths and minor excavations to improve the conspicuousness of such areas during construction, maintenance, or repair and when it is not necessary to specifically indicate a direction of movement.

The target value of cones used in a localized manner at roadworks sites may be increased by inserting a red flag in the top of one or more cones. Similarly lighting devices may be located on top of selected cones to enhance their conspicuousness both by day and night.

Device 7460

Traffic cones used for channelization purposes may be supplemented by more directional channelizing devices such as delineators (see Section 7.3.5).

7.3.4.2

BARRIER AND BARRICADE DESIGN PARAMETERS

7.3.4 BARRIERS AND BARRICADES The most commonly used types of barrier are the steel W-section guardrail and the concrete barrier. Both types may be used for temporary installation during roadworks when safety requirements match those specified for their normal permanent application. The design parameters for

Barriers are permanent or temporary devices placed on or adjacent to the roadway at hazardous locations that are capable of physically preventing vehicles from leaving the traveled

7-21

Version 0.1


temporary installations of these barriers should conform to those applicable to a permanent installation. Concrete barriers may, however, be used in a "portable" form in the sense that they are placed on the road surface in a temporary position and may be moved about, using the appropriate equipment. When manufactured for use in this manner, temporary concrete barriers should be provided with some form of proven connecting device. This may be as simple as providing recesses near the top and bottom of each end of a section of barrier to permit the use of coupling plates which will allow the barrier to be bolted together. Heavy vehicular impact with such connected portable concrete barriers may result in limited movement of one or more barriers. If zero deflection under impact is required, the portable barriers must be pinned to the road surface on which they are placed, in addition to being connected together longitudinally.

CHEVRON signs 7456 and 7457 should comprise a minimum of three chevrons for unidirectional barricades and six chevrons (three right plus three left) for bidirectional barricades. Optionally, one or more KEEP RIGHT (or LEFT) signs 7327 (or 7328) may be mounted on top of a unidirectional barricade for additional directional visual impact. The height of the MULTIPLE CHEVRON sign should be 400 millimeters for approach speeds of 60 km/h or less and 600 millimeters for higher approach speeds. The barricade should be mounted so that the lower edge is at least 1200 millimeters above ground level in order to be clearly seen above any other channelization devices such as traffic cones. BARRICADE control device 7460 should be 200-millimeters, 300-millimeters, or 400-millimeters high and five modules long, giving lengths of 1000 millimeters, 1500 millimeters or 2000 millimeters.

Barricades may be directional or nondirectional. Directional barricades should comprise a combination of temporary MULTIPLE CHEVRON signs 7456 and 7457 and KEEP RIGHT (or LEFT) sign 7327 (or 7328). The MULTIPLE

The various types of barricades are illustrated in Figure 7-6 and Figure 7-7.

SIGN 7327

SIGN 7328

SIGN 7327

SIGN 7457

SIGN 7456

Detail 7-6-1: Minimum Barricade, Left (directional)

Detail 7-6-2: Enhanced Barricade, Right (directional)

Mandatory Signs 7321 to 7328 SHALL NOT be used with SIGN 7458 SIGN 7458

Detail 7-6-3: T-Junction (Road Closed Ahead) Barricade (directional)

Figure 7-6 Examples of Directional Barricade Devices

Version 0.1

7-22


1 meter minimum 2 meters maximum 200 mm to 300 mm

15 0

mm 150

mm

45º 1.0 meter minimum

Type of support varies

2 meters minimum 200 mm to 300 mm

2.0 meter minimum

500 mm

mm 150

15 0

mm

45º

Figure 7-7 Examples of Nondirectional Barricade Devices

7-23

Version 0.1


7.3.4.3

BARRIER AND BARRICADE APPLICATIONS

more and should taper from the edge of the traveled way at a rate of 1 in 6 or preferably 1 in 10. If such a treatment is not possible the end of the barrier must be offset as much as possible and be tapered over at least three sections of barrier (6 meters) to a height of not more than 200 millimeters. The offset end must then be protected by some informal form of “crash cushion” such as sandbags or tires.

The primary temporary application of barriers as described above is to prevent vehicles leaving the traveled way or from entering the work area. Their use should be determined by engineering analysis but is likely to be particularly relevant under the following circumstances and when high volumes of traffic are present: •

• • •

Barricades should be provided behind all tapers formed by cones or delineators at major roadworks sites when the approach speed of traffic is 60 km/h or more. For any taper of 100 meters or more in length, two barricades should be provided at approximately one-quarter and three-quarters of the distance along the taper (see Section 8.4). Barriers may be used in a similar way at any other part of a deviation or detour when a shift in traffic alignment is required and space is available to accommodate the signs.

When a roadway is diverted from its normal path through a small radius curve (barriers may be required on one or both sides of the roadway). To replace a wide median when this has to be eliminated to reduce road cross-section width as part of the roadworks. To separate opposing streams of traffic on a specially constructed detour roadway. To protect vulnerable roadside features against the risk of vehicle impact.

The use of barriers at minor works is not generally warranted unless same specific circumstance such as poor sight distance or competition from advertising lighting is making visibility of the work area difficult for drivers. However, it may be necessary to protect a localized excavation from encroachment by vehicles or pedestrians. In this case the use of nondirectional BARRICADE device 7460 may be appropriate.

In the majority of the above situations, a temporary barrier will also act as a channelization device. In order that it can satisfy this function it should be light in color or conspicuously marked. A barrier may be used in conjunction with other channelization devices such as traffic cones or delineators. When used at a sharp change of direction it is recommended that the alignment of the barrier be made clear by means of SINGLE or MULTIPLE DELINEATOR signs 7454 to 7457 mounted on or above the barrier at recommended intervals (see Section 7.3.5). Warning lights may be used (see Section 7.3.8).

7.3.5 DELINEATORS Delineators are channelization devices which may be used to delineate a temporary roadway alignment. It is their function to impart a strong directional message, either to the right or to the left.

The W-section guardrail (or other similar steel guardrails) does not lend itself to frequent repositioning and should therefore only be considered for medium- to long-term installation (six weeks or more).

7.3.5.1

The introduction of short sections of temporary barrier should be avoided if possible. The risk of vehicular impact on the end of an introduced barrier should be mitigated by whatever means possible. Temporary guardrail must be provided with the same standard of end treatment as is specified for permanent installations. Approach ends of portable concrete barriers should be offset from the path of approaching traffic by 6 meters or Version 0.1

DELINEATOR SIGNS 7454 AND 7455

Signs 7454 and 7455 are temporary versions of hazard marker signs called DELINEATORS which, due to their ability to impart a directional message, warn road users of a hazard in their path on a medium- to long-term realignment of a lane or roadway and indicate the direction of movement necessary to avoid the delineated hazard.

7-24


riers, as close to the top as possible, or they should be securely mounted on top of the barriers.

Sign 7454

7.3.5.2

Signs 7454 and 7455 should not be used individually as hazard markers. The temporary version of HAZARD MARKER signs 7451 or 7452 should rather be used for this purpose.

Sign 7455

DELINEATOR DESIGN PARAMETERS

7.3.6 OBJECT MARKERS Object markers may prove useful in a roadworks traffic control situation. As the use of object markers in a roadworks situation is the same as in a typical application, instructions and guidance for their use is the same as covered in Section 6.7.

Temporary DELINEATORS signs 7454 and 7455 should conform to the dimensions given for signs 454 and 455. The minimum size of a DELINEATOR sign is 400 millimeters by 400 millimeters. Larger sizes may be used provided sufficient space is available to accommodate the sign. 7.3.5.3

7.3.7 DRUM DEVICE 7461 Drums are cylindrical containers used for channelization or delineation. Drums should have a minimum height of at least 800 mm and a minimum diameter of at least 500 mm. The markings on each drum should consist of at least two horizontal reflecting yellow and two red bands that completely encircle the drum. Each such band should be between 100 mm and 200 mm in width and if there are nonreflectorized bands between the horizontal red and yellow stripes, they should be a maximum of 50 mm wide. Only plastic

DELINEATOR APPLICATIONS

Delineators should be used to demarcate a change in alignment in exactly the same way as SINGLE CHEVRON RIGHT (or LEFT) signs 454 (or 455) as described in Section 4.3.2. They may be used on their own or to supplement other channelization devices such as traffic cones or barriers that do not give a directional message. The signs should normally be located on the outside of a sharp curve although they may be used on both sides of a curve particularly when a reverse curve is being signed.

Warning light (optional)

When used with traffic cones, delineators should be mounted on separate supports (i.e., not attached to the cones) and at such a height that they are clearly visible above the top of the cones. They should be spaced according to Table 4-3 although in cases of very sharp temporary alignment it may be beneficial to reduce these spacings. Care should be taken to ensure that all delineators are mounted at a common height above the road surface so that when seen by drivers as a series of signs they indicate changes in vertical elevation as well as horizontal alignment. Delineator signs 7454 and 7455 may also be used above and behind sections of temporary guardrail used on curving alignments. They should be used with portable concrete barriers when these are placed around curves. In this case the signs should be attached to the vertical face of the bar-

100-200 mm

Minimum total height: 800 mm

100-200 mm

100-200 mm

100-200 mm

May be nonreflective

Device 7461

7-25

Version 0.1


drums should be used. The red and yellow bands should be reflectorized with a material that has a smooth, sealed outer surface, which will have approximately the same color both day and night.

These lights are intended for use on maintenance and construction work with warnings signs, barricades, drums, reflecting panels, or other devices.

Drums should not be weighed with rocks, concrete, asphalt, sand, or any other substance to the extent that they become hazardous to motorists if struck. Generally, no more than 250 mm of sand or similar material in the bottom of a drum will be sufficient to prevent it from being moved by the wind and passing vehicles. Each drum should have drain holes in its bottom to release accumulated water.

Three types of light are available, namely: • • •

(NOTE: The Institute of Transportation Engineers [ITE] purchase specification for flashing and steady-burn warning lights is to be used with respect to color, size of lens, flash-rate, and minimum "on-time" when calling for the supply of warning lights).

Where drums are placed in the roadway, advance warning signs should also be used. During the hours of darkness, warning or delineation lights may be placed on drums in the manner described in Section 7.3.8.1. Arrow signs may be mounted on the top of drums where necessary.

Warning and delineation lights should be attached by vandal-resistant fasteners to warning and channelization devices. When the lights are placed on barricades, they should be mounted with the bottom of the lens approximately 1 meter above the ground.

7.3.8 ILLUMINATED DEVICES Despite the highest levels of attention to the safety aspects of road construction and maintenance activities circumstances do occur which drivers cannot be expected to anticipate and therefore detect a hazard. This is particularly the case at night when drivers' vision and field of view is sharply reduced.

Flashing and steady-burn yellow warning lights should have a minimum mounting height to the bottom of the lens of 1000 millimeters above the road surface. Type A lights must also be capable of sustaining 24-hour operation with a low rate of failure and should be visible on a clear night from a distance of 900 meters. Type B lights should be visible on a sunny day, without the sun being directly on or behind the light, from a distance of 300 meters. The higher-intensity light may need to be fitted with a dimming device for use during night-time.

Under these conditions it is often desirable to supplement retroreflective signs and channelization devices with illuminated devices. These can take a number of forms, the most appropriate of which are: • • •

7.3.8.2

Flashing yellow warning lights. Steady-burn yellow warning lights. Yellow warning arrow panels.

7.3.8.1

WARNING ARROW PANELS SIGN 7462

Yellow warning arrow panels should conform to the general requirements given in Table 7-3. The minimum legibility requirements given in the table are based on the concept of conforming to decision sight distance requirements and requires driver comprehension on a sunny day or a clear night.

WARNING AND DELINEATION LIGHTS

Yellow warning lights should consist of a portable, enclosed, lens-directed, battery-operated light which should be capable of being illuminated to flash or operate in a steady-burn mode.

Version 0.1

Low-intensity flashing warning light (ITE Type A). High-intensity flashing warning light (ITE Type B). Steady-burn light (ITE Type C).

7-26


Sign 7462 (typical)

Type

Minimum Size

1 2 3

600 mm x 1200 mm 750 mm x 1500 mm 1200 mm x 2400 mm

Table 7-3 Warning Arrow Panels Minimum Number Minimum Lamp of Panel Lamps Candlepower 12 1000 13 7000 15 8800

The arrow panels should be rectangular, solidly constructed, and finished in a semi-matt black material. The panels may be mounted on fixed supports or on a trailer or vehicle. The minimum height to the underside of the sign from the road surface should be 2.2 meters although it is recommended that vehicle-mounted panels be positioned as high as is practical.

Warning arrow panels should be capable of variable operation so that any of the following modes may be selected: • • • •

Warning arrow panels should also conform to the following requirements: • • • •

Minimum Legibility Distance 800 m 1200 m 1600 m

Left flashing arrow. Right flashing arrow. Left and right flashing arrows. A general caution indication involving the use of four or more lamps in a nondirectional pattern.

Recent advancements in display technologies have paved the way for light emitting diode (LED) panels to be widely used in traffic-related display signs. LEDs are diodes that have been specially designed to emit light rather than heat during their operations. The long duration life provided by LED-based technology as well as its inherent low power consumption requirements considerably reduce the operating and maintenance costs of the LED-based panel and dramatically improves the visual display technology. The LED panel is typically provided with an electronic photo sensor device to reduce the light output intensity automatically at night.

They should be capable of being dimmed to 50 percent of their rated lamp voltage. The lamp flash rate should be between 25 and 40 flashes per minute. The minimum lamp "on-time" should be 50 percent for arrows. The lamp (or lenses) should be recessed or provided with a screening hood to prevent "phantom" effects caused by sunlight striking the lamps (or lenses).

7-27

Version 0.1


7.3.8.3

ILLUMINATED DEVICE APPLICATIONS

maintenance vehicles, is likely to be limited although they may be beneficial at longer-term fixed local maintenance sites.

Steady-burn warning lights (ITE Type C) are appropriate for supplementing other forms of channelization device, if, after a drive-through inspection of the site it is considered that the retroreflective devices used need further enhancement either by night or by day. Steadyburn warning lights may, for instance, be used in conjunction with traffic cones to delineate the traveled way through detour tapers or curves. The recommended rate of use is one light to every second cone (or at spacings equal to double the appropriate cone spacings if used with a continuous barrier; see Table 7-2).

Warning arrow panels should also be used to supplement other traffic control devices used for channelization purposes. While warning arrow panels cannot be expected to solve difficult traffic problems by themselves, they may be effective in reinforcing the intention of the other devices. Their use is particularly appropriate in the following circumstances: • •

Low-intensity flashing warning lights (ITE Type A) may be used to continually warn drivers of the commencement of a hazardous or potentially hazardous area when they must exercise particular care. They may be used in conjunction with advance warning signs, barriers, or cones located on the approach to a roadworks site. They should not be used for delineation purposes because a series of flashing lights may in fact make the intended vehicle path less obvious. Long lines of uncoordinated but closely spaced flashing lights may also create random fluctuating light patterns which could be distracting to drivers.

•

The most likely benefit to be achieved by using a long-range device such as the warning arrow panel is that drivers will tend to change lanes in the required direction (indicated by arrow) earlier than they might otherwise do so, resulting in improved merging of the parallel traffic streams. If this is a requirement of the site under consideration, use of a warning arrow panel is warranted. The panel should be positioned in a safe position, preferably behind other delineation devices, at the start of the taper or other change in direction. Warning arrow panels can be particularly effective on high-volume, high-speed roads when traffic tends to obscure many of the other channelization devices.

High-intensity flashing warning lights (ITE Type B) may be used in similar circumstances to lowintensity lights to identify the most serious of hazards. Their use is particularly appropriate when a hazard is sufficiently severe that it needs to be identified to drivers in daylight. In certain circumstances, yellow rotating beacons may be used as an alternate form of ITE Type A or Type B flashing warning lights. The light from a rotating beacon is not directed, but is transmitted in all directions. As such. use of rotating beacons should be limited to vehicle-mounted applications (since changing vehicle positions relative to traffic may make a unidirectional flashing light ineffective) or at fixed locations where misdirected light is screened such that uninvolved motorists are not distracted.

Type 1 arrows are appropriate to low-speed urban streets whereas Type 2 is appropriate for intermediate speeds and for moving maintenance operations on high-speed roads. Type 3 arrow panels should be specified for high-volume, high-speed traffic flows through construction sites (see Table 7-3).

The application of warning lights during shortterm maintenance activities, other than on the Version 0.1

To provide long-range warning of a temporary change in direction of a road, particularly at the end of a long, straight approach. To similarly give long-range warning to drivers of a lane closure in support of standard diagrammatic warning signs. To provide a high-visibility sign for slowmoving maintenance operations when the warning arrow panels should be mounted on a separate vehicle that is running at the rear of the moving train of maintenance vehicles. The vehicle carrying the arrow should also be equipped with other appropriate signs and with vehicle flashing lights.

7-28


7.3.9 FLOODLIGHTING

controls and the reasons for their use. It is also essential that the workers involved in the traffic control are well trained in their tasks.

From time-to-time, the work area of a roadworks zone will be floodlighted to permit construction work to occur during hours of darkness. Such may be particularly the case with maintenance activities executed at nighttime to take advantage of low traffic volumes.

7.4.1 HAND SIGNALING Hand signaling devices such as STOP-SLOW paddles, red flags, or warning lights may be used manually to control traffic through restricted work zones.

Care must be taken to ensure that the placement of floodlights do not result in light shining directly toward approaching traffic, creating glare in the eyes of drivers. If floodlighting is used within a roadworks zone the site safety officer should check the adequacy of its placement. This is best done by driving the roadworks zone in each direction of travel to observe any floodlighting glare problems.

STOP-SLOW sign 7308 should be at least 600 millimeters wide. It should be fitted with a rigid handle and should be made of light-weight rigid or semirigid material. The sign should be retroreflective for use at dusk, night, or dawn. STOPSLOW control may be used to control construction vehicles as they enter the traffic stream within a roadworks site, or it can be used to control one-way movement within a site or alongside maintenance operations such as resealing or chipand-spray activities. The control requires two operators equipped with paddles, one at each end of a section. The actions of the operators should be controlled by means of hand-held two-way radios when the site is lengthy. One of the operators should be nominated to be in charge of the operation. The use of STOP-SLOW paddles on a one-way section of road requires the allowance of a clearance period during which both operators should display a STOP indication. On long sites, operators should communicate with each other regularly and should identify the last vehicle to enter the section if the ends of the section are not inter-visible.

Roadways in a roadworks zone should be illuminated for all high-speed or high-volume roadways or in areas with difficult geometry. Generally, the illumination of a roadworks area should conform to the same lighting criteria applicable for the permanent roadway it is located on. The requirements of the Department for the permanent roadway should equally apply to the roadworks zone.

7.4

OTHER FORMS OF TRAFFIC CONTROL

It is the nature of road construction and maintenance sites that they cannot always work in a free-flow condition of vehicular and pedestrian movement.

Red or fluorescent red flags, a minimum of 600 millimeters square, made of a durable and cleanable material may be used to control traffic in a similar manner by means of standard "STOP" signals. Red flags may also be used by a single flagman in a localized emergency situation to warn traffic of another form of control ahead, or to take particular care and be prepared to stop if necessary. Flagmen are responsible for traffic safety and have a high degree of contact with the motorist. In selecting personnel to operate as flagmen, site safety officers should look for the following qualities:

At some stage localized traffic control may become necessary when a major part of the site width needs to be occupied by workers and equipment. It should be the primary function of any form of traffic control involving the occasional stopping of traffic that it move vehicles and pedestrians as safely and effectively as possible through or around the work area while at the same time protecting workers and equipment. When considering the use of the forms of traffic control mentioned below it is essential that good public relations be pursued through the various news media by publicizing the existence of the

7-29

Version 0.1


• • • • • •

Good physical condition including sight and hearing. Average intelligence. Mental alertness. An ability to communicate with the public in a courteous but firm manner. A neat appearance. A strong sense of responsibility for the safety of the public and site staff.

driver of the last vehicle in the group following the pilot car should be given a small red flag to hand to the flagger at the other end of the section. The pilot car should be light weight and easy to handle. The name of the contractor or contracting authority should be prominently displayed on the vehicle. The pilot car sign should be visible from the rear of the vehicle. A flashing yellow beacon may be mounted on the top of a pilot car for additional identification.

Flagmen must wear high-visibility clothing in fluorescent red or yellow. At night they should wear a retroreflective vest or jacket of yellow, white, or in a patterned combination of these colors. Notwithstanding these requirements, care must also be taken to ensure that the clothing of flagmen contrasts with their working environment and other colors may be necessary.

Two or more pilot cars may be needed to guide two-way traffic through a complex or hazardous detour.

7.4.3 TEMPORARY TRAFFIC SIGNALS Temporary traffic signal installations may be used in a similar manner to the hand signals described in Section 7.4.1 to control alternating one-way traffic at a location within a roadworks site not normally subjected to such control.

Flagmen must be sited sufficiently far in front of a STOP position that drivers have enough time in which to stop when required. They should stand on the shoulder adjacent to the lane being controlled or in the closed lane, well clear of the traveled way, within the protection of barricades if possible. Advance warning FLAGMAN AHEAD sign 7442 (or STOP-SLOW CONTROL AHEAD sign 7443, as appropriate) must be in position before the flagging operation starts. Under no circumstances should a flagman stand in a running traffic lane. Flagmen should not allow other workers to congregate around their station. They should, as part of the their duties, be aware of other workers in their vicinity who may be in danger if a driver fails to obey his signal, and should be able to issue an audible warning to them. At night, flagman stations must be adequately illuminated.

The equipment used should conform to all standards and specifications normally imposed for the supply and installation of permanent traffic signals except that the switching may be specified to be manually operated or vehicle-actuated via temporary induction loops. The timing equipment should be capable of being calibrated to offer sufficiently long all-red intervals between directional switching to permit traffic to clear the controlled section before the release of an opposing flow. Typical applications of such temporary traffic signals include: •

7.4.2 PILOT CAR A pilot car can be used to guide a group of vehicles through a work area or detour. It is especially effective when the route is relatively long, hazardous, complicated, or frequently changed. The operation of the pilot car must be coordinated with the flaggers at each end of the section, as in the case of the flag-carrying car.

•

Any long one-way section of roadway operated in this way must be carefully checked to ensure that vehicles cannot enter or leave the section anywhere between the end control points.

Sufficient room must be provided for the pilot car to turn around at each end of the section. The

Version 0.1

One-way through sections of roadway adjacent to the work area (including maintenance operations). At temporary junctions on a detour or deviation with temporary "haul" roads used by construction vehicles and plant.

7-30


Temporary advance warning TRAFFIC SIGNAL AHEAD signs 7430 should be located in advance of each traffic signal. If traffic signals are used to control a haul road, sign 7430 should also be placed on the haul-road approaches. If the signals on any approach are not visible from an adequate stopping-sight distance, the advance warning signs should be equipped with flashing warning lights.

7-31

Version 0.1


8 8.1

TYPICAL APPLICATIONS

signs in addition to those shown may be warranted and should be included if necessary for the safety and welfare of the public.

GENERAL

8.2

AT-GRADE JUNCTIONS

The purpose of this chapter is to provide graphical representations of how regulatory signs, warning signs, guide signs, pavement markings and roadworks devices are used in various typical roadway situations. The figures that make up this chapter are largely graphical and illustrative in nature. Specific dimensions for placement of the traffic control devices are generally not shown so as to discourage manual users from designing from Chapter 8 alone. Guidance for the design of various traffic control devices should be obtained as appropriate from other chapters in this Manual and used with discretion relative to the actual circumstances and configuration being confronted by the designer.

This section illustrates typical combined applications of the use of regulatory signs, warning signs, guide signs and pavement markings for atgrade junctions. Where relevant to the situation being illustrated traffic signals are also indicated. There is a great deal of scope for variation in geometric detail with the majority of applications illustrated. This section should not be seen as a guideline for geometric design. Similar but differently detailed geometric layouts should be signed and marked according to the illustrated principles.

In each of the figures, color representations of each pavement marking and sign are shown to aid the manual user in visualizing the relationships of the various elements. For each figure in this chapter, a cross-referenced section includes notes with comments, directions, exceptions, or information that is pertinent to the situation depicted by the figure.

Figure 8-1 depicts several representative configurations of situations found on local access roads within a community. The sizes of signs and pavement markings are shown in a relative scale and are based on a speed limit of 40 kilometers per hour.

The configurations and guide signs shown on the following applications are hypothetical and do not necessarily represent actual locations in Abu Dhabi. They are intended solely to represent typical signing for a given configuration of roadway or junction. Signing and pavement marking positionings shown represent preferred locations. To the maximum extent possible, signing locations should be considered in the geometric design of a roadway with provisions made in the roadside design to accommodate these signs. When signing existing configurations the locations indicated should be followed to the maximum extent possible, but some variation may be found unavoidable.

1. Join adjacent sections of NO PASSING LINE marking 611 when less than 32 meters apart. 2. Break in NO PASSING LINE marking 611 at junctions should be a minimum of 8 meters, centered on intersecting road centerline. 3. Paint all curbs within junctions and on curves with VISIBILITY PAINTING marking 691. The use of VISIBILITY PAINTING marking 691, as illustrated, is intended to help identify junctions under limited or adverse lighting conditions. In general, therefore, the sections of marked curbs illustrated should not be connected unless the unmarked section between is less than 8 meters in length. 4. The use of MULTIPLE CHEVRON signs 456, 457 and 458 is optional. These signs should not be used unless lighting, background, or geometry obscure the presence of a termination or change in direction of the

8.2.1 ROAD JUNCTIONS IN COMMUNITY AREAS

NOTES:

In general, the signing shown in the following applications are considered minimum (unless signs are indicated as being optional). While it is desirable to minimize the number of signs used,

8-1



690(900x900) 690(900x900)

690(900x900)

690(900x900)

Figure 8-1 Road Junctions in Community Areas


8-2


roadway alignment. Ordinarily the change in roadway direction will be evident as a result of pavement markings otherwise required; curb painting; and/or street lighting. 5. See Chapter 3, Section 3.2.2 for determination of use of STOP sign 301 versus GIVE WAY sign 302. 6. Recommended setbacks for STOP LINE marking 601 and GIVE WAY LINE marking 602 are typically one meter as shown. Greater setbacks may be required to accommodate left turning traffic depending on intersection geometry. The absolute minimum setback should be 500 millimeters.

4.

5.

6.

8.2.2 ARTERIAL MIDBLOCK U-TURN AND LOCAL ROAD TJUNCTION

7.

Figure 8-2 depicts two typical situations on a 6 lane dual carriageway. One situation is a midblock U-turn located away from an intersecting roadway and intended solely for the purpose of making U-turns (Figure 8-3 depicts a similar situation on a four-lane dual carriageway where a midblock U-turn and left turn are combined). The other situation is a local road T-junction with an arterial. The junction depicted in this figure is only provided with radii on the corners. (Figure 8-3 shows a similar configuration, but with short tapers to facilitate turning.) The sizing of signs and pavement markings are shown in a relative scale and are based on a speed limit of 60 kilometers per hour on the divided road and 40 kilometers per hour on the intersecting road.

located at a point as close as possible after the turn lane becomes fully developed. If the geometry is such that any sized vehicle may make a U-turn, then sign 351 is omitted and, apart from STOP sign 301, no further signing is required. See Chapter 3, Section 3.2.2 for determination of use of STOP sign 301 versus GIVE WAY sign 302. Paint curbs with VISIBILITY PAINTING marking 691 only in relation to the U-turn lane and its opening in the median, and the immediate vicinity of the side road junction. LANE LINE marking 654 should not be marked within the vehicle swept area at the U-turn. Geometric design should clearly indicate the prohibition of opposing traffic entering the median opening. In situations where geometry does not clearly make that evident appropriate regulatory signs may be utilized to prohibit such entries.

8.2.3 ARTERIAL MIDBLOCK LEFT TURN AT LOCAL ROAD TJUNCTION Figure 8-3 depicts a situation on a four-lane dual carriageway where left turns through a median opening from a divided road are permitted onto an intersecting local road. The sizes of signs and pavement markings are shown in a relative scale and are based on a speed limit of 60 kilometers per hour on the divided road and 40 kilometers per hour on the intersecting road. Figure 8-2 shows similar circumstances for a six-lane dual carriageway.

NOTES: 1. Advance warning for midblock U-turns should be posted and the distance to the point of U-turn displayed. 2. Appropriate ADVANCE SUPPLEMENTAL sign 514 may be used only when an approved supplemental destination is in the vicinity (see Chapter 5, Section 5.1.5). 3. When geometry dictates that long vehicles are not permitted to make a U-turn, a NO GOODS VEHICLES sign 351 with a QUALIFICATION PLATE sign 365 indicating the maximum length of vehicle permitted to Uturn should be used. Sign 351 should be

NOTES: 1. ADVANCE WARNING sign 419 for a midblock left turn should be posted and the distance to the point of left turn displayed. 2. Under these circumstances a U-Turn would not normally be permitted due to right turning traffic from the junction opposite. Therefore a NO U-TURN SIGN 348 should be posted 25 meters in advance of the turning point. If however, geometric conditions warrant a limited U-Turn movement permissible then long vehicles will be prohibited from

8-3



7 6

KEY: *

Optional Sign

5

Note Number See Section 8.2.2

620(100)

654 R or 654 N/R

4

Figure 8-2 Arterial Midblock U-Turn and Local Road T-Junction


8-4


612 or 612 N 620(100)

7

5

654 R or 654 N/R

Optional Sign Note Number See Section 8.2.3 365(900)

Figure 8-3 Arterial Midblock Left Turn at Local Road T-Junction

8-5



3.

4.

5.

6.

7.

8.2.4 SERVICE ROAD CONNECTIONS TO AN ARTERIAL

making U-Turns at such locations by placement of a U-TURN AHEAD sign 419 with a QUALIFICATION PLATE sign 365, depicting a goods vehicle with a red diagonal bar running from the top right hand corner to the bottom left hand corner of the sign, limiting the restriction to only goods vehicles and busses etc., over a prescribed length (generally 6 meters). A bus lay-by is shown. Taxi lay-bys should be treated similarly. In general, private vehicles are prohibited from stopping in these exclusive lay-bys in order to keep them free for use by buses or taxis respectively. In instances where it is wished to allow private vehicles to use a lay-by for drop-offs, the layby should be divided into two segments using a PARKING LINE marking 621. The first segment is reserved for buses by posting a BUS STOP sign 392. The following segment is posted with a NO PARKING sign 379 which allows any vehicle (private, taxi or bus) to stop but not park within the designated area. When a U-turn is permitted, EDGE LINE marking 613 should be set back because of the two-lane carriageway if necessary to allow vehicles to make a U-turn without crossing that line. GIVE WAY sign 302 is required in the configuration illustrated since the right turn does not have a full acceleration taper. In instances where median U-Turns are permitted, then a STOP sign 301 should be used instead, since the junction already has one STOP sign 301 (at the median turn). If a full designed acceleration taper is provided then neither a GIVE WAY sign not STOP sign would be used at the right turn. LANE LINE marking 654 should not be marked within the U-turn/Left Turn junction area. Geometric design should clearly indicate the prohibition of opposing traffic entering the median opening. In situations where geometry does no clearly make that evident appropriate regulatory signs may be utilized to prohibit such entries.


Figure 8-4 depicts a number of typical situations that are commonly found on service roads adjacent to arterial roadways. The sizes of signs and pavement markings are shown in a relative scale and are based on a speed limit of 60 kilometers per hour on the main road, 40 kilometers per hour on secondary roads, and 25 kilometers per hour on service roads (same sizing as 40 kilometers per hour). This figure also illustrates a typical mid-block signalized pedestrian crossing. NOTES: 1. PARKING TIME LIMIT signs 389 and 391 are shown to illustrate one possible application of parking control signs. A variety of other applications is also possible. 2. ONE WAY sign 306 is shown in this situation to indicate that the service road is one way in the direction stipulated, but to not inhibit drivers from entering the main road with a more or less straight ahead movement. 3. NO PARKING marking 690 may be used in situations such as this where vehicles may have a tendency to illegally park, but where a sign prohibiting parking would be difficult to site to give a proper indication of intent and/or the restricted areas are small. 4. NO ENTRY sign 304 is shown in this instance since sight restrictions inhibit visibility of a ONE WAY sign 306 from the side road. 5. PEDESTRIAN CROSSING marking 603 is specifically used in this situation as an added safety precaution because of sight distance. With the building lines near the side road as illustrated, crossing pedestrians would be difficult to see until they are actually in the road. The use of PEDESTRIAN CROSSING marking at other pedestrian crossing points must be considered on a location-by-location basis. In general, on service roads where pedestrians can be in the road at any place for purposes of accessing parked cars, the installation of painted crossings is generally not warranted.

8-6


654 R or 654 N/R

KEY : *

Optional Sign

1

Note Number See Section 8.2.4 Traffic Signal

7 Typical 654 R or 654 N/R

4

5

Figure 8-4 Service Road Connections to an Arterial

8-7



6. A mid-block signalized pedestrian crossing is shown crossing the main roadway and service roads. Priority control on the main roadway should be by traffic signal. Pedestrian priority on the service roads is provided by GIVE WAY TO PEDESTRIANS sign 303. 7. VISIBILITY PAINTING marking 691 should be used in the vicinity of all service road connections to and from the main roadway and at junctions between side roads and the main roadway and service roads. For more detail see Figures 8-1 to 8-3.

5. If street lighting poles are present and located symmetrically with respect to each approach, preference should be given to mounting STREET NAME sign 516 thereon. 6. Paint all curbs within junction and vicinity with VISIBILITY PAINTING marking 691 (not shown in Figure 8-5). As a guideline marking 691 should commence at approximately the same point as marking 612. 7. If the exit leg of a junction enters or is adjacent to a community the name of the community may be displayed on a TEXT sign 588 on the right side of the road at a suitable distance before the first local street junction serving the community. 8. The free right turn has been illustrated for the situation where it intersects the crossroad without a fully developed acceleration lane. If a full acceleration lane is present then a treatment as shown in Figure 8-7 should be used. 9. Depending on the length of the right turn lane the positioning of signs 508 (or 514) and 512 (or 511) may require adjustment. None should be located after the start of the turn lane taper and the distances between signs carefully controlled. Preferred spacing is 50 meters minimum.

8.2.5 LARGE ROUNDABOUT Figure 8-5 depicts a representative configuration of a full size roundabout. The sizes of signs and pavement markings are shown at a relative scale and are based on a speed limit of 60 kilometers per hour on the approach roads. Signing is shown only for one approach. Other approaches are similar (see Figure 8-6 for details relevant to signalization). NOTES: 1. ADVANCE HORIZONTAL STACK sign 511 may be required in place of ADVANCE VERTICAL STACK sign 512. See Chapter 2, Section 2.2.4 for criteria and Figure 8-6 for a typical example. Such advance signs should be located as far in advance of the roundabout as possible and practical (up to 250 meters), subject to other criteria given in Chapter 5. 2. Appropriate TRAILBLAZER sign or ADVANCE SUPPLEMENTAL sign 514 may be used only when an approved trailblazing or supplemental destination is in the vicinity. See Chapter 5 for guidance on approved destinations. In general, a CHEVRON DIRECTION sign 515 should not be used for a supplemental destination. 3. MULTIPLE CHEVRON RIGHT sign 456 should be used only if the visible presence of the roundabout is not clear to approaching drivers due to geometry or surroundings. 4. LANE ARROWS shown are indicative only. Actual arrows used in each lane should be based on traffic-engineering analysis of the junction.


8.2.6 LARGE SIGNALIZED ROUNDABOUT Figure 8-6 depicts a representative configuration of a signalized roundabout. The sizes of signs and pavement markings are shown at a relative scale and are based on a speed limit of 60 kilometers per hour on the approach roads. Signing is shown only for one approach. Other approaches are similar. NOTES: 1. Figure 8-6 should be read in conjunction with Figure 8-5 and Section 8.2.5. Figure 8-6 is an adaptation to illustrate the effects of signalizing the junction shown in Figure 8-5. 2. The free right turn has been illustrated for the situation where it intersects the crossroad without a fully developed acceleration lane. If a full acceleration lane is present then a

8-8


603(3000) 603(3000)

329(900) 612 or 612 N

427(900)

614/615

654 R or 654 N/R

420(900)


Note: This figure illustrates traffic control device principles for one approach direction only. Application of devices for other approaches and configurations should be done based on the illustrated principles and using good engineering judgement.

Figure 8-5 Large Roundabout

8-9



613(150) 603(3000) 601(300) 329(900)

613(150)

612 or 612 N

427 (900) With Flasher

614/615 612 or 612 N

654 R or 654 N/R Note Number See Section 8.2.6

420(900)


Figure 8-6 Large Signalized Roundabout


8-10


3.

4.

5.

6.

7.

8.

treatment as shown in Figure 8-7 should be used. Depending on the length of the right-turn lane the positioning of signs 430, 514 and 511 (512) may require adjustment. None should be located after the start of the turnlane taper and the distances between signs should be carefully controlled. Preferred spacing is 50 meters minimum. TRAFFIC SIGNALS AHEAD sign 430 may be used for a period of three to six months when traffic signals are installed on an existing unsignalized roundabout. The preferred location of the CHEVRON DIRECTION sign 515 is on the channelizing island formed by the free right-turn lane. If insufficient space is available on the island sign 515 may be placed on the right side of the road at the beginning of curve. In such case a PASS EITHER SIDE sign 326 should be located in the island. CHANNELIZATION LINE marking 612 for the right-turn lane is one standard length (L=27 meters for 60 kilometers per hour; see Chapter 6, Table 6-3) measured from the curve point of the turning lane. See Chapter 3, Section 3.2.2 for determination of use of STOP sign 301 versus GIVE WAY sign 302. If the exit leg of a junction enters or is adjacent to a community the name of the community may be displayed on a TEXT sign 588 on the right side of the road at a suitable distance before the first local street junction serving the community.

2.

3.

4.

5.

6.

7.

8.2.7 SIGNALIZED INTERSECTION Figure 8-7 depicts a representative configuration of a signalized junction. The sizes of signs and pavement markings are shown at a relative scale and are based on a speed limit of 60 kilometers per hour on the approach roads. Signing is shown only for one approach. Other approaches are similar.

meters). If should be located no closer to the intersection than the beginning of taper for the left or right turn lane if a closer siting must be used. Appropriate ADVANCE SUPPLEMENTAL sign 514 may be used only when an approved supplemental destination is in the vicinity (see Chapter 5, Section 5.1.5). The preferred location of the CHEVRON DIRECTION sign 515 is on the channelizing island formed by the free right turn lane. If insufficient space is available in the island sign 515 may be placed on the right side of the road at the beginning of curve. In such case a PASS EITHER SIDE sign 326 may be located in the island. Intersection is shown with pedestrian crossings. This may not be required in all locations and would thus be omitted when not applicable. Configuration shown assumes design of adequate acceleration lanes for free flow merge condition. CHANNELIZATION LINE marking 612 for the development of the left-turn lane is shown at double the standard length (2L=54 meters for 60 kilometers per hour). This is due to the left-turn lane being a dual lane and the need for traffic to enter the lanes further from the intersection. The CHANNELIZATION LINE for the right-turn lane is one standard length (L=27 meters for 60 kilometers per hour; see Chapter 6, Table 6-3) measured from the curve point of the turning lane. Paint all curbs within junction and vicinity with VISIBILITY PAINTING marking 691 (not shown). Marking 691 should commence before the start of any added turn lane and terminate after the junction beyond the end of any merge lanes.

8.2.8 FREEWAY CROSSROAD WITH SMALL ROUNDABOUTS Figure 8-8 depicts a representative configuration of a junction at the terminal end of a freeway grade separated interchange. The junction represented is a dual roundabout configuration on an undivided crossroad with assumed speed of 60 kilometers per hour. Figures 8-5, 8-6, or 8-7 may be referred to for applicable signing and pave-

NOTES: 1. ADVANCE HORIZONTAL STACK sign 511 should be located as far from the intersection as possible and practical (up to 250

8-11



5 m min

612 or 612 N

654 R or 654 N/R

7

330 (750) 365 (Truck)

6

348 (750)

612 or 612 N

KEY : *

Optional Sign

1


ALT

Alternate Sign Position Traffic Signal


Figure 8-7 Signalized Intersection


8-12



4

399(600x800)

1 5

398(600x800) 1

1


Figure 8-8 Freeway Crossroads with Small Roundabouts

8-13



ment markings if other junction configurations are used at an interchange terminal end. Signing is shown only for traffic coming from the bottom of the figure and from the left of the figure. Signing for other approaches is similar.

with a speed limit of 60 kilometers per hour. Signing is only shown for traffic coming from the bottom of the figure and from the left of the figure. Signing for other approaches is similar. NOTES:

NOTES: 1. See Figure 8-11 for positioning of signs 399 and 512 on the exit ramp. The position of sign 398 on the entrance ramp is similar. 2. The potentially most dangerous aspect of a diamond interchange is the possibility of vehicles entering a freeway in the wrong direction from an exit ramp. Subject to the detail of the geometry of the junctions between ramps and the crossroad, pairs of NO ENTRY sign 304 are recommended to inhibit wrong way entry to a ramp. These NO ENTRY signs 304 should be mounted on the traffic signal posts. In addition to NO ENTRY sign 304, other applicable signs (NO RIGHT TURN sign 347 and AHEAD ONLY sign 321) as well as LANE DIRECTION ARROWS (on the crossroad and ramps) and red RPM R markers on the ramps should all be employed to reinforce the NO ENTRY message 3. CHEVRON signs 515 at the action points for the turns onto the freeway may also need to be relocated if the junction islands are not large enough to accommodate them, or if visibility of them is likely to be obstructed by other signs, such as NO ENTRY sign 304 and STOP sign 301. 4. Paint all curbs within the vicinity of the ramp terminal junctions with VISIBILITY PAINTING marking 691 (not shown). 5. As a result of the potential for crossroad traffic to mistakenly turn left too soon and enter a freeway exit ramp, care must be taken in deciding upon the configuration and placement of the ADVANCE VERTICAL STACK sign 512. If the diamond ramps are widely separated then it is preferable to direct left turning traffic straight through the first half of the diamond junction. A single stack ADVANCE VERTICAL STACK sign may then be used to direct the left turning traffic if such can be suitably located. Otherwise, the CHEVRON DIRECTION sign 515 at the turn point must be relied upon to direct the left turning traffic.

1. See Figure 8-11 for positioning of signs 399 and 512 on the exit ramp. The position of sign 398 on the entrance ramp is similar. 2. Double roundabouts create two separate points of decision for traffic which must use both roundabouts to reach their destination. Therefore, pairs of ADVANCE VERTICAL STACK sign 512 are required to navigate drivers through the junction one decision at a time. The second sign in the series must be positioned where geometry best permits. This example shows placement within the roundabout. If clear distance between the roundabout pair exceeds about 75 meters, then placement of the sign between the roundabouts is preferred. 3. Typically NO ENTRY signs 304 are not required on exits from roundabouts due to ramp-end geometry. However, where there is even a remote possibility of drivers entering a freeway traveling in the wrong direction, resulting in almost certain serious consequences, the posting of a pair of NO ENTRY signs is justified. 4. Paint all curbs within junction and vicinity with VISIBILITY PAINTING marking 691 (not shown). 5. MULTIPLE CHEVRON RIGHT sign 456 should be used only if the visible presence of the roundabout is not clear to approaching drivers due to geometry or surroundings.

8.2.9 FREEWAY CROSSROAD AT A SIGNALIZED DIAMOND INTERCHANGE Figure 8-9 depicts a representative configuration of a junction between a dual carriageway crossroad and a freeway in the form of a signalized grade-separated diamond interchange. The junction type is subject to wide variations in geometric treatment. The example illustrated assumes a dual-carriageway numbered-arterial crossroad


8-14


See Section 8.2.9

612 or 612 N

3


Figure 8-9 Freeway Crossroad at a Signalized Diamond Interchange

8-15



8.2.10 MINI ROUNDABOUT

8.3.1 FREEWAY WITH ONE-LANE EXIT, NO LANE DROP

Figure 8-10 depicts a representative configuration of a junction between two intersecting single carriageway roads in the form of a mini roundabout. The junction is subject to wide variations in geometric treatment. The example illustrated assumes a standard crossroad junction between two local roads.

Figure 8-11 depicts the configuration of a single lane exit ramp. As depicted the lane used to exit the freeway is a lane which is shared between ongoing traffic and exiting traffic. (See Section 8.3.2 for the treatment for a two-lane exit.) Figure 8-11 is presented based upon an interchange located on an Emirate Route that is a freeway. It is also applicable for non-freeway exits and/or exits on Abu Dhabi Routes. The sizes of signs and pavement markings are shown at a relative scale and are based on a speed limit of 100 kilometers per hour.

NOTES: 1. A mini roundabout configuration will not, under normal circumstances be used at the junction of numbered routes. Therefore no guide signing applications are shown in Figure 8-10. 2. Where the median of a roundabout is not raised and curbed, two EDGE LINE markings 613 spaced 150 millimeters apart should be used to delineate the mini roundabout. 3. GIVE WAY sign 302 along with GIVE WAY marking 602 will be used in the same manner as shown for a Large Roundabout in Figure 8-5. 4. ROUNDABOUT sign 329 should be mounted on the same post and directly below GIVE WAY sign 302 to direct drivers to travel in a circulatory fashion through the junction as with a standard roundabout configuration. 5. ROUNDABOUT AHEAD sign 420 is shown on only one leg of the roundabout to emphasize that its use is not necessary in all situations, but is determined based on engineering judgement and site distances.

8.3

NOTES: 1. For a simple access type interchange on an uncomplicated alignment, an EXTRA FORWARD ADVANCE EXIT DIRECTION sign 551 is not required nor is a second ONGOING DESTINATION sign 553 required at the exit point. 2. Appropriate SUPPLEMENTAL EXIT sign 557 may be used only when an approved supplemental destination is in the vicinity (see Chapter 5, Section 5.1.5). Sign 557 is typically ground mounted but may be mounted overhead if determined appropriate. 3. The spacing of retroreflective RPM marking R for EDGE LINE marking 613R should be reduced to four meters within the gore area. 4. Omit FREEWAY END sign 399 when not applicable such as on a freeway-to-freeway ramp at a systems interchange. 5. The specific significance of the manner of display of the various signs is that for a full width display there is a Type 7 arrow centered over each lane and the ADVANCE EXIT DIRECTION signs 551 are located over the right side lane which is also available to ongoing traffic. If a second lane is developed on the off-ramp, the ADVANCE EXIT DIRECTION sign 551 and the EXIT DIRECTION sign 552 should only show one arrow. The second lane should not be marked until approximately 100 meters beyond the 552 signs. 6. ADVANCE EXIT DIRECTION sign 551 would not normally be required for an

GRADE-SEPARATED JUNCTIONS

This section deals principally with sequences of guide signs for a range of typical freeway gradeseparated interchanges. Basic pavement marking arrangements for typical free-flow exit conditions are also illustrated. The principles illustrated are equally applicable to isolated grade separated junctions on non-freeway routes. Details of the terminal treatment of typical off-ramp and on-ramp situations are covered in Section 8.2.


8-16


456 (400x1200)

329 (600) 302 (750) 302 (750)

420 (750) * 5

329 (600) 456 (400x1200)

329 (600)

456 (400x1200) 302 (750) 3

302 (750) 329 (600) 4

456 (400x1200)

603

See Section 8.2.10

Figure 8-10 Mini Roundabout

8-17



50 m min

654 R or 654 N/R

R/2 250 m max

(100 km/h) 0m

5

500 m 6

See Section 8.3.1

1000 m

Figure 8-11 Freeway with One-Lane Exit, No Lane Drop


8-18


uncomplicated alignment. However, site specific geometry, such as a merging collectordistributor (C-D) road after FORWARD ADVANCE EXIT DIRECTION sign 551, will at times require ADVANCE EXIT DIRECTION sign 551 to be used.

6. The specific significance of the manner of display of the various signs is that for a full width display there is a Type 7 arrow centered over each lane. In this instance the number of lanes prior to the exit is four and the number after the exit is three. For this reason the shared exit and ongoing lane is the second lane from the right in advance of the exit and the right side lane drops at the exit. It is necessary to display two exit arrows on the ADVANCE EXIT DIRECTION signs 551 and the EXIT DIRECTION sign 552. There are therefore only two ongoing lanes indicated on ONGOING sign 553. 7. ADVANCE EXIT DIRECTION sign 551 would not normally be required for an uncomplicated alignment. However, site-specific geometry, such as a merging C-D road after FORWARD ADVANCE EXIT DIRECTION sign 551, will at times require ADVANCE EXIT DIRECTION sign 551 to be used.

8.3.2 FREEWAY WITH TWO-LANE EXIT, ONE LANE DROP Figure 8-12 depicts the configuration of a two lane exit ramp from a freeway with one lane being dropped at the exit and the second being an optional exit lane. As depicted the dropped lane can only be used to exit the freeway. The adjacent lane is shared between ongoing traffic and existing traffic (see Section 8.3.1 for the treatment for a single exit lane.) Figure 8-12 is presented based upon an interchange located on an Emirate Route that is a freeway. It is also applicable for nonfreeway exits and/or exits on Abu Dhabi Routes. The sizes of signs and pavement markings are shown at a relative scale and are based on a speed limit of 100 kilometers per hour.

8.3.3 INTERCHANGE WITH A C-D ROAD

NOTES: Figure 8-13 depicts an interchange in the form of a cloverleaf with a C-D road. Figure 8-13 is presented based upon a single-lane exit (not a lane drop). The sizes of signs are shown at a relative scale and are based on a speed limit of 100 kilometers per hour. Regulatory and warning signs and pavement markings are not shown.

1. For a simple access type interchange on an uncomplicated alignment, an EXTRA FORWARD ADVANCE EXIT DIRECTION sign 551 is not required nor is a second ONGOING DESTINATION sign 553 required at the exit point. 2. Appropriate SUPPLEMENTAL EXIT sign 557 may be used only when an approved supplemental destination is in the vicinity (See Chapter 5, Section 5.1.5). Sign 557 is typically ground mounted but may be mounted overhead if determined appropriate. 3. The spacing of retroreflective RPM marking R for EDGE LINE marking 613R should be reduced to four meters within the gore area. 4. Omit FREEWAY END sign 399 when not applicable such as on a freeway-to-freeway ramp at a systems interchange. 5. See Chapter 6, Table 6-3 for appropriate minimum value of L. For lane drops on roadways with posted speeds in excess of 70 kilometers per hour, a 200-millimeter wide CHANNELIZING LINE marking 612 should be used.

NOTES: 1. EXTRA FORWARD ADVANCE EXIT DIRECTION sign 551 and/or second ONGOING DIRECTION sign 553 at the exit point may be added if interchange complexity and location warrants (see Chapter 5, Section 5.6.4). 2. Second EXIT DIRECTION sign 552 is shown located in advance of the overpass rather than at the theoretical gore (painted nose) to prevent overpass from obscuring the drivers view of the sign. If the interchange is large and the distance between the front side of the overpass and the exit to the loop ramp exceeds 150 meters it may be beneficial to provide a second ADVANCE EXIT DIREC-

8-19



50 m min

654 R or 654 N/R

R/2 250 m max

(100 km/h) 0m

250 m

500 m 553 (x=300)

551 (x=300) 7

See Section 8.3.2 654 R or 654 N/R 6

1000 m 551 (x=300)

Figure 8-12 Freeway with Two-Lane Exit, One Lane Drop


8-20


0m

500 m

See Section 8.3.3

1000 m

Figure 8-13 Interchange with a C-D Road

8-21



3.

4. 5.

6.

7.

TION sign 551, displaying the appropriate distance, prior to the structure with an EXIT DIRECTION sign 552 located at the theoretical nose. The EXIT DIRECTION sign for the second exit is displayed with an "EXIT" (Lane Drop) panel even though corresponding ADVANCE EXIT DIRECTION signs do not have the "EXIT" (Lane Drop) panels. This is due to the short auxiliary lane developed between the entering and exiting loop ramps and the need to advise entering drivers to leave that lane or be forced to exit. If by design the speed limit on the C-D road is reduced to less than 100 kilometers per hour, sign letter size for signs on the C-D road may be reduced accordingly. See Figure 8-11 for pavement markings for this configuration. If the exit lane configuration is different the EXIT DIRECTION sign 552 may need to be varied to indicate more than one lane and/or a lane drop situation. It is a basic principle of the guide signing system that there should never be more arrows displayed at one point across the roadway than there are lanes on the road. ADVANCE EXIT DIRECTION sign 551 would not normally be required for an uncomplicated alignment. However, site specific geometry, such as a merging C-D road after FORWARD ADVANCE EXIT DIRECTION sign 551, will at times require ADVANCE EXIT DIRECTION sign 551 to be used.

NOTES: 1. The EXIT DIRECTION sign for the second exit is displayed with an "EXIT" (Lane Drop) panel even though corresponding ADVANCE EXIT DIRECTION signs do not have the "EXIT" (Lane Drop) panels. This is due to the short auxiliary lane developed between the entering and exiting loop ramps and the need to advise entering drivers to leave that lane or be forced to exit. 2. The sign positioning for second EXIT DIRECTION sign 552 is subject to whether the approach is at an overpass or an underpass (see Section 8.3.3). 3. It is a basic principle of the guide signing system that there should never be more arrows displayed at one point across the roadway than there are lanes on the road.

8.3.5 FREEWAY SYSTEMS INTERCHANGE WITH A TWOLANE EXIT AND RAMP SPLIT Figure 8-15 depicts a systems (freeway to freeway) interchange with a two lane exit that splits shortly after the exit point. Figure 8-15 is presented based upon the ramp split not being a lane drop (two lanes continue to left destination and one lane exits from the ramp to right destination) and being located less than 500 meters from the first exit. The sizes of signs are shown at a relative scale and are based on a speed limit of 100 kilometers per hour. Regulatory and warning signs and pavement markings are not shown.

8.3.4 FREEWAY SYSTEMS INTERCHANGE WITH TWO CLOSELY SPACED EXITS

NOTES: 1. When the distance between the exit and the ramp split exceeds about 500 meters, consideration should be given to including an ADVANCE EXIT DIRECTION sign 551 between the exit and the ramp split. 2. It is a basic principle of the guide signing system that there should never be more arrows displayed at one point across the roadway than there are lanes on the road. The display shown at the theoretical nose must therefore be positioned so that the exit sign arrows are fully over developed exit lanes.

Figure 8-14 depicts a systems (freeway to freeway) interchange with two closely spaced exits directly from the mainline. Figure 8-14 is presented based upon successive single lane exits, neither of which are lane drops. The sizes of signs are shown at a relative scale and are based on a speed limit of 100 kilometers per hour. Regulatory and warning signs and pavement markings are not shown.


8-22


0m

500 m

1000 m

See Section 8.3.4

2000 m

Figure 8-14 Freeway Systems Interchange with Two Closely Spaced Exits

8-23



0m

500 m

1000 m

See Section 8.3.5

2000 m

Figure 8-15 Freeway Systems Interchange with a Two-Lane Exit and Ramp Split


8-24


8.3.6 FREE-FLOW RAMP CONDITIONS

usually involves substandard geometry, the use of signs sized one size greater than those given in Table 2-1 is recommended (up to the maximum sizes listed).

Figure 8-16 depicts pavement marking conditions that are not otherwise covered in an incidental manner in other figures in this chapter. Pavement marking sizes are based on a speed limit of 100 kilometers per hour. The retroreflective version of pavement markings are shown for a freeway condition. For non-freeway conditions the standard version of the markings may be used.

Diagrammatic signs and high-visibility background signs should have minimum sizes as follows (exclusive of SUPPLEMENTARY PLATE sign 7589): • •

NOTES:

See various sections of Chapter 7 for sizing of cones, barricades, and other roadworks traffic control devices.

1. The spacing of retroreflective RPM marking R for EDGE LINE marking 613R should be reduced to four meters within the gore area. 2. When the length of the auxiliary lane exceeds 1000 meters, the entrance and exit ramps should be treated independently. If the auxiliary lane is 600 meters to 1000 meters in length, then it should be marked as shown. If the auxiliary lane is less than 600 meters long, the CHANNELIZATION LINE marking 612R at the exit should be replaced by a section of ENHANCED LANE LINE marking 655R of at least equal length.

8.4

Speeds 60 kilometers per hour or less: 1200 mm by 1600 mm. Speeds over 60 kilometers per hour: 1800 mm by 2400 mm.

8.4.1 TYPICAL TAPER DETAIL — TRANSITION AREA Figure 8-17 depicts a left-lane closure on a multilane roadway. If two lanes are being closed, each lane should be closed using a separate taper and the respective tapers should be separated by a suitable stabilization area between them. Rightlane closures are treated similarly (see also Figure 8-24).

ROADWORKS NOTES:

The figures in this section represent typical details appropriate to the layout of a traffic control zone as described in Chapter 7, Section 7.1.2, and general arrangements of typical applications of these details. Local site conditions will vary significantly but it is extremely important that whenever possible all sites be signed according to the basic principles given in Chapter 7, Section 7.1.2, and that the sequences of traffic control zones conform to the provisions of Figure 7-1 in Chapter 7. Adherence to these principles will give the best chance that the site will function with safety and that traffic flow will be maintained even under fairly severe congestion.

1. High-speed signing option should be used for all but minor and/or short-term roadwork sites. The number of KEEP RIGHT signs 7327 or KEEP LEFT signs 7328 (with or without MULTIPLE CHEVRON BARRICADE device 7456) placed within a taper should be increased as taper lengths become longer. Engineering judgment should be used, but in general the spacing between signs should not exceed 50 meters (or the taper length divided by 4 for longer tapers). 2. For length of taper and spacing of cones see Chapter 7, Figure 7-1 and Table 7-2 respectively. 3. Cones should be spaced at taper spacing for the first 25 to 50 meters of the stabilization area. Thereafter spacing may be increased as indicated in Chapter 7, Table 7-2.

Roadworks signs may be sized in accordance with Table 2-1, Regulatory and Warning Sign Sizes (in Chapter 2), when roadworks geometry equals or exceeds standard roadway design criteria. However, since roadworks configurations

8-25



Detail 8-16-1: Tapered On-Ramp 654 R or 654 N/R

Detail 8-16-2: Free-Flow Weaving Section Weaving Section (1000 meters maximum)

2

Detail 8-16-3: Deceleration Lane with Taper

5 m min

KEY: L: See Table 6-3 W: Lane Width Design 1 Note Number

See Section 8.3.6

Figure 8-16 Free-Flow Ramp Conditions


8-26


KEY: 5

Note Number See Section 8.4.1 3

Direction of Travel

Stabilization Area

Flashing Light

1

7327(1200) High Speed Signing

Minimum Signing

7327(750) 7456(600x1800) 7327(1200)

7459

Transition Area

7456(600x1800) 7327 (1200) 7327(750) 7327 (1200)

7466 (1200 x 1800) 7418(900)

7466 (1200 x 1800)

7589(200m)

7466 (1200 x 1800)

Advance Warning Area

7418 (900)

7589(600m) 7589(600m)

7441 (900)

800m

7589(800m)

7441 (900) 800m

7589(800m)

Figure 8-17 Typical Taper Detail — Transition Area

8-27



4. On roadways with shoulders the line of cones delineating the taper should be extended forward into the advanced warning area to taper out the shoulder. 5. Existing pavement markings that conflict with the configuration of the roadworks should be removed on long-term roadworks sites or covered using a black traffic tape on short-term roadworks sites.

cone spacing appropriate to the taper rates given in Chapter 7, Table 7-2. 2. Cones should be spaced at taper spacing for the last 25 to 50 meters of the stabilization area. 3. When a roadworks site has required a reduction in speed limit over an extended area the normal roadway speed limit should be posted after the termination area. The speed limit shown in this example is illustrative only. The speed limit posted should be that of the roadway in the absence of the roadworks.

8.4.2 TYPICAL CROSSOVER DETAIL — TRANSITION AREA

8.4.4 SHORT WORK SITE — TWO-WAY TRAFFIC

Figure 8-18 depicts a traffic crossover situation that would be used to bypass a closed section of one side of a dual-carriageway roadway. A similar configuration would be used with a right-hand curve to leave the main carriageway and enter a separately constructed temporary roadway.

Figure 8-20 depicts a situation wherein a portion of a two-way single carriageway serving light volumes of local traffic must be partially closed for short-term maintenance or repairs, but still retains open a portion of the carriageway sufficiently wide to carry two-way traffic.

NOTES: 1. Length of transition area should at minimum be equal to the length of equivalent taper calculated as per Chapter 7, Figure 7-1 based on the total displacement of the crossover. 2. Opposing traffic streams should be separated from each other by a BARRIER device on long-term and/or high-speed roadworks sites. When BARRIERS are used, care should be taken at end treatments to remove the leading end of the BARRIER at least six meters laterally from oncoming traffic. 3. A CHANNELIZING LINE marking 612 is recommended throughout the length of the crossover unless high geometric standards are achievable. 4. Conflicting existing pavement markings should be removed and new markings placed to define temporary lanes and alignments.

NOTES: 1. For long term construction or if in an area with significant traffic volumes, a treatment similar to that shown in Figure 8-18 should be considered. 2. If sufficient width is not available for two vehicles then the roadway should be closed to traffic in one direction and that traffic detoured (see Figure 8-22). Alternatively, for operations of one-day duration or less, twoway traffic may be controlled by one or two flagmen using a STOP-SLOW sign 7308. 3. See Figure 8-17. 4. See Figure 8-19.

8.4.5 WORK SITE CLOSE TO SIDE ROAD

8.4.3 TYPICAL TAPER DETAIL — TERMINATION AREA

Figure 8-21 depicts a situation wherein a work site is located near to a side road junction. The configuration illustrated depicts a work site ahead of the junction but is equally applicable for a work site occurring just beyond a junction. The signing shown illustrates an urban situation on a roadway posted at 80 kilometers per hour.

Figure 8-19 depicts a typical roadworks termination configuration. NOTES: 1. Termination taper rates may be 50 percent or less of an equivalent transition taper with


8-28


7441(200)


Figure 8-18 Typical Crossover Detail — Transition Area

8-29



KEY: 2

Note Number See Section 8.4.3 Direction of Travel

Figure 8-19 Typical Taper Detail — Termination Area


8-30


150 m

100 m

50 m

0m

5.5 m min

0m

50 m

100 m

150 m

Figure 8-20 Short Work Site — Two-Way Traffic

8-31



6

KEY: 2

Note Number See Section 8.4.5 Direction of Travel

0m

200 m

400 m

600 m

800 m

Figure 8-21 Work Site Close to Side Road


8-32


NOTES:

2. The road closure is shown with a fixed barricade at one end and a movable barricade at the other end. The movable barricade may be offset sufficiently to allow vehicular access. Barricade lengths and arrangements will vary to suit conditions at a particular site. 3. Flashing warning lights should be affixed to the barricades to provide additional emphasis of the road closure to approaching through drivers. 4. NO LEFT (RIGHT) TURN signs 7346 and 7347 may be placed as appropriate for the benefit of drivers who may intend to turn left or right onto the roadway now closed. These signs should be omitted if the barricade closing the roadway provides sufficient notice to drivers.

1. The use of high-visibility backgrounds and diagrammatic warning signs is recommended for roadways posted at 80 kilometers per hour and above. A sign size of 1800 by 2400 (excluding SUPPLEMENTARY PLATE sign 7589) is recommended for these signs. 2. See Figure 8-17. In an urban area speed reductions may be necessary to allow shorter, slow speed tapers to be used. This condition is illustrated. 3. Existing STOP sign 301 may be retained if suitably positioned. If GIVE WAY sign 302 exists, it should be temporarily removed and replaced by a STOP sign. 4. Provide a revised STOP LINE marking 601 at a one-meter setback (or as appropriate) using white traffic tape. Remove existing STOP LINE or temporarily cover with black traffic tape. 5. Existing pavement markings that conflict with the configuration of the roadworks should be removed on long-term roadworks sites or covered using a black traffic tape on short-term roadworks sites. 6. See Figure 8-19.

8.4.7 MAINTENANCE WORK Figure 8-23 depicts a situation whereby a mobile work team, usually a maintenance operation, must occupy a portion of one of the carriageways of a multilane roadway. If maintenance operations are static and/or long term, then roadworks traffic control treatment should follow a conventional approach. Figure 8-23 depicts a right-lane maintenance operation. Left-lane operations are handled similarly.

8.4.6 ROAD CLOSURE DETOUR Figure 8-22 depicts a situation wherein a section of roadway within a community roadway system must be completely closed to traffic. In such a case it is desirable to guide traffic, which would otherwise be using the temporarily closed roadway, around the closure. The signing illustrated is appropriate for the situation shown. Many variations are possible depending on the roadway layout and road closure location.

NOTES: 1. ROADWORKS sign 7441 should be placed 600 meters in advance of the start of the work for the day. As work progresses, all advance signs should be moved forward so that the maintenance operation is never more than three kilometers ahead of the ROADWORKS sign. 2. All maintenance vehicles working on or near the roadway should be equipped with flashing yellow warning lights. 3. The primary maintenance vehicle and the shadow vehicle should be equipped with a suitable high-visibility rear panel. The design of the rear panel may vary to suit the vehicle configuration, but should have the general arrangement as shown. Included on the rear panel should be a changeable KEEP RIGHT (or LEFT) sign 7327 and 7328 that can be

NOTES: 1. CHEVRON DIRECTION signs 7515 with the destination name "Detour" are provided for the guidance of traffic disrupted by the road closure (These signs do not require drivers to turn in the direction indicated). If the road closure involves a numbered route, then the route number emblem and control destination of the route may be used on sign 7515.

8-33



Figure 8-22 Road Closure Detour


8-34


0m

300 m

600 m

(For 3 km)

(For 3 km)

Figure 8-23 Maintenance Work

8-35



8.4.9 MINOR-ROAD SINGLE-LANE OPERATION

positioned to direct approaching traffic to pass on the intended side.

8.4.8 TYPICAL TWO-LANE TAPER DETAIL — TRANSITION AREA

Figure 8-25 depicts a short-term roadwork situation where half of a minor, low-volume community road is closed to construct a utility crossing. This detail may be invoked only when traffic volumes are extremely light, the intervisibility of conflicting traffic is not obstructed by the construction or other sight obstructions, and the roadway is opened fully to traffic at the end of each work day. If any of these conditions are not met, a complete closure of the roadway is required with a detouring of affected traffic (see Figure 8-22). Alternatively, traffic may be manually controlled/coordinated by flagmen each using a STOP/SLOW sign 7308, or through the use of temporary traffic signals.

Figure 8-24 depicts the closure of two lanes on a multilane roadway by a single taper extending over the two closed lanes. This practice is not generally recommended as it is likely to result in a greater than normal risk of accidents on the approach to the taper. The practice is also very likely to result in traffic congestion on the approach even under moderate flows. In spite of the recommendations above there will be times when such a taper has to be provided, usually in an emergency. The need for the use of a two-lane taper is likely to stem from a lack of necessary advance length to provide for the preferred two separate tapers with an intermediate stabilization area (see Figure 8-17 and Chapter 7, Figure 7-1).

When the construction activity it situated near a junction, the give-way control should remain on the side road, regardless of which half of the carriageway is blocked. When the construction activity is located well away from a junction the give-way control should regulate the traffic whose lane is blocked by construction.

NOTES: 1. Spacing between the KEEP RIGHT signs 7327 (or KEEP LEFT signs 7328) should not exceed 50 meters (or the taper length divided by 4 for long tapers). The minimum signing option is only appropriate for very short-term (under 24 hours) or short-term (up to 72 hours) installations. 2. For length of taper and spacing of cones see Chapter 7, Figure 7-1 and Table 7-2 respectively. 3. Cones should be spaced at taper spacing for the first 25 to 50 meters of the stabilization area. Thereafter spacing may be increased as indicated in Chapter 7, Table 7-2. 4. On roadways with shoulders the line of cones delineating the taper should be extended forward into the advance warning area to taper out the shoulder. 5. Existing pavement markings that conflict with the configuration of the roadworks should be removed on long-term works sites.


8.5

SCHOOL ZONE

Figure 8-26 depicts typical applications for a school zone. School zones should be established on all streets where school children enter or exit a school or a school compound, on foot, directly onto the street. Where the side of a school or school compound does not have a gate or door leading directly onto the street, no school zone should be established on the adjacent street. If a gate or door exists but is not used by children on foot or if the gate or door is buffered from the street by a frontage road or closed parking lot, no school zone should be established. NOTES: 1. If warranted, a school zone should be established for, at a minimum, the entire length of the school compound facing the zone and, at a maximum, up to 150 meters past the school boundary in either direction. The extent to which a school zone extends beyond the school boundary up to 150 meters should be

8-36


3

5

2

4

Figure 8-24 Typical Two-Lane Taper Detail — Transition Area

8-37



Figure 8-25 Minor-Road Single-Lane Operation


8-38


1

Note Number See Section 8.5

SCHOOL 5

3

C

A

2

B

4

B

A

C 6

100 Meters

Installation A

End School Zone

Start School Zone

Installation B

Installation C

Figure 8-26 School Zone

determined by the engineer on site, depending on prevailing approach speeds and visibility. 2. To warn drivers that they are approaching a school zone, an advance warning sign, shown as installation A, should be placed 100 meters in advance of the school zone. 3. The beginning of a school zone should be marked with installation B. Installation B includes a 30-kilometer-per-hour speed-limit sign with a supplemental plate indicating school. Both signs are bilingual in English and Arabic. 4. The beginning of a school zone should also be communicated with nonreflective raised pavement markings. These markings are to be installed in three rows, staggered, in a 0.50-meter width perpendicular to the traffic direction. If the street is not divided, the pavement markings should extend across both lanes at either end of the school zone. If the street has a median separating traffic directions, the pavement markings need only be placed where traffic will enter the school

zone. There is no need to place pavement markings at the end of a school zone in a street divided by a median. 5. The end of a school zone should be marked by Installation C. 6. A school zone should be marked for both directions of traffic, even if the street is divided by a median. If there is a fence in the median preventing pedestrians from crossing outside of a crosswalk, the lane of the street not adjacent to the school should not be marked for a school zone. Local traffic and pedestrian conditions may require different applications or solutions for marking school zones. Engineers are expected to exercise their professional judgement on site, in the spirit of these general guidelines and with the purpose of protecting school children from traffic conditions.

8-39



9

SIGNALS

9.1

GENERAL

Actuated operation: A type of traffic control signal operation in which some or all signal phases are operated on the basis of actuation.

9.1.1 INTRODUCTION

Actuation: Traffic-demand initiation of a change in or extension of a traffic signal phase through the operation of any type of detector.

A traffic control signal is defined as a power-activated traffic control device by which traffic is warned or is directed to take some specific action, such as stop or proceed.

Approach: All lanes of traffic moving towards an intersection or a mid-block location from one direction, including any adjacent parking lane(s). Average day: A day representing traffic volumes normally and repeatedly found at a location, typically a weekday when volumes are influenced by employment or a weekend when volumes are influenced by entertainment or recreation.

The functions of traffic signals are: • • •

To organize control conflicting traffic movements (including pedestrians and bicycles). To warn of possible danger. To assist tidal flow of traffic.

Backplate: A thin strip of material that extends outward from and parallel to a signal face on all sides of a signal housing to provide a background for improved visibility of the signal indications.

Standards for traffic control signals are important because traffic control signals need to attract the attention of every road user. This includes those users who are older, those who suffer impaired vision but are within legal driving requirements, those who may be fatigued or distracted, and those who, for whatever reason, are not expecting to encounter a signal at a particular location. Standards for traffic control signals are also important because signals need to function autonomously and reliably under a wide range of conditions and must effectively communicate their message to drivers in sunlight and in darkness, in adverse weather, and in visually complex surroundings.

Beacon: A highway traffic signal with one or more signal sections that operates in a flashing mode. Conflict monitor: A device used to detect and respond to improper or conflicting signal indications and improper operating voltages in a traffic controller Controller assembly: A complete electrical device mounted in a cabinet for controlling the operation of a highway traffic signal.

This chapter contains a number of required and recommended procedures and techniques related to traffic signals in Abu Dhabi. These include methods of analysis and design, operational procedures, and examples of design and installation.

Controller unit: That part of a controller assembly that is devoted to the selection and timing of the display of signal indications. Crosswalk: a) That part of roadway at an intersection included within the connections of the lateral lines of the sidewalks on opposite sides of the highway measured from the curbs or in the absence of curbs, from the edge of the traversable roadway, and in the absence of a sidewalk on one side of the roadway, the part of a roadway included within the extension of the lateral lines of the sidewalk at right angles to the centerline. b) any portion of a roadway at an intersection or elsewhere distinctly indicated for pedestrian crossing by lines or other markings on the surface.

9.1.2 DEFINITIONS The following technical terms, when used in this chapter, are defined as follows: Accessible pedestrian signal: A device that communicates information about pedestrian timing in nonvisual format such as audible tones, verbal messages, and/or vibrating surfaces.

9-1



Cycle: One complete sequence of signal indications.

use of specific lanes of a roadway or to indicate the impending prohibition of such use.

Dark mode: The lack of all signal indications at a signalized location. (The dark mode is most commonly associated with power failures, ramp meters, and beacons.)

Louver: A device that can be mounted inside a signal visor to restrict visibility of a signal indication from the side or to limit the visibility of the signal indication to a certain lane or lanes.

Detector: A sensing device used for determining the presence or passage of vehicles or pedestrians.

Major street: The street normally carrying the higher volume of vehicular traffic. Minor street: The street normally carrying the lower volume of vehicular traffic.

Emergency vehicle traffic control signal: A special traffic control signal that assigns the right-of-way to an authorized emergency vehicle.

Pedestrian change interval: An interval during which the flashing UPRAISED HAND (symbolizing DON'T WALK) signal indication is displayed.

Flasher: A device used to turn highway traffic signal indications on and off at a repetitive rate of approximately once per second.

Pedestrian clearance time: The time provided for a pedestrian crossing in a crosswalk, after leaving the curb or shoulder, to travel to the center of the farthest traveled lane or to a median.

Full-actuated operation: A type of demandbased traffic control signal operation in which all signal phases function on the basis of actuation.

Pedestrian signal head: A signal head, which contains the symbols WALKING PERSON (symbolizing WALK) and UPRAISED HAND (symbolizing DON'T WALK) that is installed to direct pedestrian traffic at a traffic control signal.

Highway traffic signal: A power-operated traffic control device by which traffic is warned or directed to take some specific action. These devices do not include power-operated signs, illuminated pavement markers, barricade warning lights, or steady-burning electric lamps.

Permissive mode: A mode of traffic control signal operation in which, when a CIRCULAR GREEN signal indication is displayed, left or right turns may be made after yielding to pedestrians and/or oncoming traffic.

Intersection: The area embraced within the prolongation or connection of the lateral curb lines, or if none, the lateral boundary lines of the roadways of two highways that join one another at, or approximately at, right angles, or the area within which vehicles traveling on different highways that join at any other angle may come into conflict. The junction of an alley or driveway with a roadway or highway does not constitute an intersection.

Platoon: A group of vehicles or pedestrians traveling together as a group, either voluntarily or involuntarily, because of traffic signal controls, geometrics, or other factors.

Interval: The part of a signal cycle during which signal indications do not change.

Preemption control: The transfer of normal operation of a traffic control signal to a special control mode of operation.

Interval sequence: The order of appearance of signal indications during successive intervals of a signal cycle.

Pretimed operation: A type of traffic control signal operation in which none of the signal phases function on the basis of actuation.

Lane-use control signal: A signal face displaying signal indications to permit or prohibit the

Priority control: A means by which the assignment of right-of-way is obtained or modified.


9-2


Protected mode: A mode of traffic control signal operation in which left or right turns may be made when a left or right GREEN ARROW signal indication is displayed.

Signal phase: The right-of-way, yellow change, and red clearance intervals in a cycle that are assigned to an independent traffic movement or combination of movements.

Pushbutton: A button to activate pedestrian timing.

Signal section: The assembly of a signal housing, signal lens, and light source with necessary components to be used for providing one signal indication.

Ramp control signal: A highway traffic signal installed to control the flow of traffic onto a freeway at an entrance ramp or at a freeway-to-freeway ramp connection.

Signal system: Two or more traffic control signals operating in signal coordination.

Red clearance interval: An optional interval that follows a yellow change interval and precedes the next conflicting green interval.

Signal timing: The amount of time allocated for the display of a signal indication. Signal visor: That part of a signal section that directs the signal indication specifically to approaching traffic and reduces the effect of direct external light entering the signal lens.

Right-of-way (assignment): The permitting of vehicles and/or pedestrians to proceed in a lawful manner in preference to other vehicles or pedestrians by the display of signal indications.

Signal criteria: A threshold condition that, if found to be satisfied as part of an engineering study, should result in analysis of the traffic conditions or factors to determine whether a traffic control signal or the improvement is justified.

Roadway network: A geographical arrangement of intersecting roadways. Semiactuated operation: A type of traffic control signal operation in which at least one, but not all, signal phases function on the basis of actuation.

Speed limit sign beacon: A beacon used to supplement a SPEED LIMIT sign.

Signal coordination: The establishment of timed relationships between adjacent traffic control signals.

Steady (steady mode): The continuous illumination of signal indication for the duration of an interval, signal phase, or consecutive signal phases.

Signal face: The front part of a signal head. Stop beacon: A beacon used to supplement a STOP sign, a DO NOT ENTER sign, or a WRONG WAY sign.

Signal head: An assembly of one or more signal faces together with the associated signal housings.

Traffic control signal (traffic signal): Any highway traffic signal by which traffic is alternately directed to stop and permitted to proceed.

Signal housing: That part of a signal section that protects the light source and other required components.

Visibility — limited signal face or signal section: A type of signal face or signal section designed to restrict the visibility of a signal indication from the side, to a certain lane or lanes, or to a certain distance from the stop line.

Signal indication: The illumination of a signal lens or equivalent device. Signal lens: That part of the signal section that redirects the light coming directly from the light source and its reflector, if any.

Walk interval: An interval during which the WALKING PERSON (symbolizing WALK) signal indication is displayed. When a verbal mes9-3



•

sage is provided at an accessible pedestrian signal, the verbal message is “WALK” sign. Warning beacon: A beacon used only to supplement an appropriate warning or regulatory sign or marker.

9.1.4 AREA OF CONTROL A traffic control signal should control traffic only at the intersection or midblock location at which it is placed. The selection and use of traffic control signals should be based on an engineering study of roadway, pedestrian, bicyclist, and other conditions (warrants) in comparison to the minimum conditions under which installing traffic control signals might be justified.

Yellow change interval: The first interval following the green interval during which the yellow signal indication is displayed.

9.1.3 ADVANTAGES AND DISADVANTAGES OF TRAFFIC CONTROL SIGNALS

Adequate roadway capacity should be provided at signalized locations in order to reduce the inherent delays resulting from alternating assignment of right-of-way at intersections controlled by traffic control signals.

Traffic control signals assign the right-of-way to the various traffic movements and thereby profoundly influence traffic flow. A traffic control signal that is properly designed, located, operated, and maintained will have one or more of the following advantages: • • • • •

•

9.1.5 TYPES OF TRAFFIC CONTROL SIGNALS

It may reduce the number of some types of accidents, particularly right-angle accidents. It will result in more orderly movement of traffic. It will give drivers and pedestrians safer opportunities to cross a street. It may increase the number of vehicles safely going through the intersection. Under favorable conditions, the operation of adjacent signals or groups of signals may be coordinated to permit the continuous or nearly continuous movement of traffic along a street or on a street grid. It may be used to interrupt heavy traffic at intervals to permit other traffic to cross.

Traffic control signals at a specific intersection may be either pretimed or traffic actuated. A pretimed signal is a type of traffic control signal in which the cycle, phasing, intervals, and indications are predetermined and do not vary. They are repeated until changed manually or by a control mechanism such as a clock or master controller. A traffic-actuated signal is a type of traffic signal in which the length of most intervals and the cycle, and in some types the sequence of phasing, are varied by the demands of traffic. The timing, intervals, sequence, and phasing of pretimed traffic control signals are generally predetermined but can be changed by time clock or other automatic control. In traffic-actuated equipment, these features are constantly varied by traffic demand.

An improper or unjustified traffic control signal can result in one or more of the following disadvantages: • • • •

It may cause unnecessary delay to traffic. It may cause an increase in accidents (particularly rear-end collisions) Increased use of less adequate routes as road users attempt to avoid the traffic control signals. Excessive disobedience of the signal indications.


The installation of a traffic control signal should be considered only if the good effects outweigh the bad effects.

Both types of control may be included in a system composed of traffic signal controllers at several intersections whose operation is coordinated for efficient traffic flow. The critical features of the position, visibility, and permissible sequence of signal indications are the same for all types of traffic control signals.

9-4


•

9.1.6 PORTABLE TRAFFIC CONTROL SIGNALS A portable traffic control signal should be used only when a signal is needed for a short time emergency situation or for a work area (typically less than 30 days). It should be used only when an engineering study shows a signal is required. A portable traffic control signal should not be used if a flagman or police officer can economically and safely direct traffic. A portable traffic control signal should not be used at a school crossing.

•

9.2.1.2

When used, a portable traffic control signal should meet all of the physical, display, and operational requirements in this Part. “SIGNAL AHEAD” signs should always be used on the approaches to a portable traffic control signal.

9.2

•

TRAFFIC CONTROL SIGNAL INDICATIONS

•

Uniformity in the design features that affect the traffic to be controlled is especially important for safe and efficient traffic operations. Engineering judgment should be used to determine the proper phasing and timing for a traffic control signal. Since traffic flows and patterns change, phasing and timing should be re-evaluated regularly and updated accordingly.

•

Traffic, except pedestrians, facing a steady AMBER DISK or AMBER ARROW indication is warned that the movement which had been allowed by the corresponding green indication is being terminated. A steady AMBER DISK or AMBER ARROW indication tells pedestrians that there is no longer sufficient time to cross the roadway before a red indication is shown. A flashing AMBER DISK indication is typically used in the Emirate of Abu Dhabi to indicate a permissible right turn movement and mid-block pedestrian crossings.

9.2.1.3

GREEN TRAFFIC SIGNAL INDICATION

RED TRAFFIC SIGNAL INDICATION

Red traffic signal indications should have the following meanings: •

Green traffic signal indications should have the following meanings: •

YELLOW TRAFFIC SIGNAL INDICATION

Yellow traffic signal indications should have the following meanings:

9.2.1 MEANING OF VEHICULAR TRAFFIC CONTROL SIGNAL INDICATIONS

9.2.1.1

Traffic, except pedestrians, facing a GREEN ARROW indication, shown alone or in combination with another indication, may cautiously enter the intersection only to make the movement specified by the arrow or by the other indication. Drivers should yield the right-of-way to vehicles and pedestrians already lawfully within the intersection or adjacent crosswalk. Pedestrians facing a GREEN DISK indication may proceed across the roadway within the crosswalk, unless prohibited from doing so by a pedestrian signal.

Traffic, except pedestrians, facing a GREEN DISK (or Green Signal Face) indication may proceed straight through an intersection or turn right or left. However, signs, pavement markings, or roadway design may prohibit or prevent one or more of those movements. Drivers should yield the right-of-way to vehicles and pedestrians already lawfully within the intersection or adjacent crosswalk. 9-5

Traffic, except pedestrians, facing a steady RED DISK or RED ARROW indication should stop at the marked stop line before entering the intersection. Traffic should remain standing until an indication to proceed is shown, except as otherwise provided for. If a marked stop line does not exist, the stop should be made before entering the crosswalk. If a marked crosswalk does not exist, the stop should be made before entering the intersection.



•

•

Pedestrians facing a steady RED DISK indication alone should not enter the roadway unless permitted to do so by a pedestrian indication.

9.2.2 USE OF TRAFFIC CONTROL SIGNAL INDICATIONS 9.2.2.1

•

NONFLASHING INDICATIONS

It should be shown only when traffic facing the signal is permitted to proceed in any direction which is lawful and practicable. However, this restriction may be modified by signs prohibiting specific movements, usually at stated times. It should not be shown at the same time to two traffic movements whose paths would cross or otherwise conflict.

A RED DISK indication is used as follows:

9.2.2.2

•

AMBER ARROW and GREEN ARROW indications should normally be used in the following locations:

•

•

It should be shown when it is intended to prohibit traffic (except pedestrians directed by a pedestrian signal) from entering an intersection or other controlled area. A traffic signal operated pedestrian crossing between intersections is an example of such a controlled area. It should not be shown with a right or left GREEN ARROW indication, which is the only other illuminated indication in that face (except as provided in Section 9.3.2). It should not be shown with the right or left AMBER ARROW change indication, which follows a GREEN ARROW indication shown alone. It should be shown with a right or left GREEN ARROW indication when traffic is allowed to turn but is not allowed to proceed straight ahead. It should also be displayed with the AMBER ARROW indication, which follows the GREEN ARROW indication in this case.

• • • •

•

An AMBER DISK indication is used as follows: •

•

•

It should be shown when it is necessary to inform approaching traffic the right-of-way is about to change, except when an AMBER ARROW indication is required (Section 9.2.2.4) It should be used instead of the AMBER ARROW indication following a GREEN ARROW indication shown alone, when the indications are visible only to traffic which these signals control.

•

At an intersection with a one-way street. Where some movements are prohibited or are physically impossible. Where there is a separate, sheltered lane intended only for specific traffic movement. Where some of the vehicular movements on an approach do not begin or end at the same time as other vehicular movements. This rule applies only when signal indications for turning vehicles are visible to other traffic on that approach. A RED ARROW indication may also be used. An AMBER ARROW indication should be used only to show a change in the right-ofway granted by a GREEN ARROW indication. This is required when the indications are visible to all traffic on the approach. When GREEN ARROW and GREEN DISK indication terminate at the same time, only a AMBER DISK indication should be shown. An AMBER ARROW indication should not be displayed when any conflicting movement has a green or amber indication. A GREEN ARROW indication should be displayed only when the path of the vehicles proceeding in the direction of the arrow: - Does not conflict with the path of other vehicles moving lawfully in response to other green or amber signal indications, and - Does not cross a crosswalk to which pedestrian WALK indications are being shown at the same time.

A GREEN DISK indication is used as follows:


ARROW INDICATIONS

9-6


9.2.2.3

PROHIBITED COMBINATIONS OF TRAFFIC CONTROL SIGNAL INDICATIONS

traffic signal controller design and operating problems. 9.2.2.4

The following combinations of traffic signal indications should not be shown simultaneously on any one signal face: • • • •

Each color, type, and combination of steady (nonflashing) traffic control signal indication in any one signal face may only be followed by the showing of an approved steady “following” display. The approved “following” displays are listed in Table 9-1 for normal operation. Additional “following” displays allowed when the signal is preempted by an emergency vehicle or a train, are shown in Table 9-2. No other “following” displays may be used.

GREEN DISK with AMBER DISK Straight-through GREEN ARROW with RED DISK. RED DISK with AMBER DISK GREEN DISK with RED DISK.

The above combinations should not be simultaneously displayed on different signal faces on any one approach, unless the following are true: •

•

•

9.3

DESIGN AND LOCATION OF VEHICULAR TRAFFIC CONTROL SIGNAL INDICATIONS

One of the signal faces controls only traffic in a lane intended only for turning vehicles and is identified as a left or right turn signal, or One of the signal faces controls only the traffic in a lane intended only for turning vehicles, and

9.3.1 SIZE AND DESIGN OF TRAFFIC SIGNAL LENSES

- The indications on that signal face are only a RED DISK (or a RED ARROW), AMBER ARROW and GREEN ARROW, and - At least the RED DISK indication is visible only to traffic it controls.

All traffic control signal lenses, including pedestrian signals, should be circular. The circular lenses should be antiphantom and should have a visible diameter closely approaching 300 millimeters. The lenses should be red, yellow (amber), or green in color.

Or, as an alternative to the above, the signal indications are screened, covered, louvered, positioned, or designed so the combination of indications is not confusing to approaching drivers.

The following traffic control signal equipment should meet or exceed the Department’s Standard Specifications and Standard Drawings. •

None of the following traffic signal indications should be used:

• •

• •

•

•

INDICATIONS THAT MAY FOLLOW OTHER INDICATIONS

A straight-through AMBER ARROW. More than two arrow indications illuminated at the same time. The combination of a AMBER DISK indication and an AMBER ARROW indication normally should not be shown. Where possible, only the AMBER DISK should be shown except in those unusual situations where elimination of the AMBER ARROW causes

Lenses, with respect to color, light transmittance, and arrow design. Reflectors, with respect to reflectivity. Complete optical units, with respect to horizontal and vertical light distribution. Wiring, housing, visors, and hardware, with respect to the pertinent electrical and mechanical characteristics.

Arrow indications should be pointed vertically upward to show a straight through movement. Arrow indications should be pointed horizontally to indicate a turn at approximately right angles. When the angle of the turn is substantially differ-

9-7



Table 9-1 (page 1 of 2) Permissible Sequential Traffic Control Signal Indications Existing Indication(s)

Permissible Following Indications in the Same Signal Face

Use Only At “T” Intersections

Notes: a. The practicality of some sequences depends on holding opposing traffic movements by appropriate signal indications. b. Other arrangements may be feasible as the need arises.


9-8


Table 9-1 (page 2 of 2) Permissible Sequential Traffic Control Signal Indications Existing Indication(s)

Permissible Following Indications in the Same Signal Face

Notes: a. The practicality of some sequences depends on holding opposing traffic movements by appropriate signal indications. b. Other arrangements may be feasible as the need arises.

9-9



Note: The practicality of some sequences depends on holding opposing traffic movements by appropriate signal indications.


9-10


ent from a right angle, the arrow should be pointed at an angle which will approximately equal that of the turn.

three other indications. However, this shall be done only when other improvements have not produced satisfactory results.

Each arrow lens should show only one arrow direction. The arrow indication should be the only illuminated part of the lens, which is visible.

In Abu Dhabi there are two permissible arrangements of indications in traffic signal faces as shown in Figure 9-1.

In no case should letters, numbers, or symbols be displayed as part of a vehicular traffic control signal indications.

9.3.2 NUMBER AND ARRANGEMENT OF INDICATIONS IN A TRAFFIC CONTROL SIGNAL FACE The indications in each traffic control signal face should be arranged in a vertical straight line. The relative positions of indications within a signal face should be as follows:

Figure 9-1 Typical Arrangements of Indications on Signal Faces

RED DISK AMBER DISK GREEN DISK

9.3.3 ILLUMINATION OF TRAFFIC CONTROL SIGNAL LENSES

or Each traffic signal lens should be illuminated separately.

Left turn RED ARROW Left turn AMBER ARROW Left turn GREEN ARROW

An unobstructed, illuminated vehicular traffic control signal indication should be sufficiently bright to be clearly visible for a distance of at least 400 meters under normal atmospheric conditions. See Section 9.6 for visibility of pedestrian signal indications.

The RED DISK indication should always be at the top of a vertical signal arrangement. When used, an AMBER DISK indication should always be located between the red indications and all other indications.

•

A single GREEN ARROW indication should be used alone to permit a continuous movement.

Signal dimmers should be provided for the amber signal sections. The dimmer should allow the signal lamp to operate at full intensity under daylight conditions and to reduce proportionally to 25 ±5 percent of full intensity at night. A dimmer should not control more than one amber section for each direction.

•

Pedestrian signal faces, which have two indications.

9.3.4 VISIBILITY AND SHIELDING OF SIGNAL FACES

One or more indications in a signal face may be repeated for safety or increased effectiveness. For instance, two red indications may be placed in adjacent vertical locations in a signal face with

Every signal head and its supports should be designed so each signal face may be aimed independently of any other signal face.

Each signal face should have at least three indications but not more than five with the following exceptions:

9-11



Every signal face should be aimed so its indications will have maximum visibility to the traffic it is intended to control. Each signal face should normally be aimed at a point approximately one meter above the approach roadway, substantially in advance of the stop line. The distance from the stop line to this point should be approximately the distance traveled by a vehicle while the driver reacts to the signal indication and stops. This distance is shown in Table 9-3. An upgrade on the approach to a signal will reduce the required vehicle stopping distance, while a downgrade will increase that distance. When the approach grade is about 5 percent or more, it would be desirable to adjust the minimum visibility distances shown in Table 9-3 to compensate for the required decrease or increase in stopping distance.

ty of the signal indications as much as practicable to the drivers the signals control. However, visors exceeding 300 millimeters in length should only be used on signal heads which are rigidly supported so that they do not swing. Street, commercial, and advertising lighting behind and in line with traffic signal indications may seriously interfere with signal visibility and effectiveness. Backplates (a strip of thin material such as sheet aluminum or sheet plastic extending outward approximately 127 millimeters parallel to the signal face on all sides of the signal housing) are available. Backplates should be used on all signal heads placed over the roadway. Backplates should also be used on all other signal heads located where background colors and lights would interfere substantially with the effectiveness of the traffic signal indications. The front surface of backplates, the inside surfaces of visors, and the entire surface of louvers and fins should have a flat dull black finish. A backplate may have a white or silver border.

Table 9-3 Required Advance Visibility of Traffic Control Signal Indications 85 Percentile Speed (km/h)

Minimum Visibility Distance (meters)

30 40 50 60 70 80 90 100 110 120

50 65 85 110 135 165 195 230 265 295

9.3.5 NUMBER AND LOCATION OF SIGNAL FACES The primary consideration in the placement of signal faces is the visibility and effectiveness of the indications. Drivers approaching a signalized intersection or other area, should be given a clear and unmistakable indication of whether they should stop, proceed, turn right or turn left. The most important physical conditions affecting visibility of the signal indications are the lateral and vertical angles of a driver's view toward a signal face. These angles are determined primarily by the height, distance beyond the intersection, and lateral placement of the signal face. Other considerations include the design of the vehicle, the curvature and gradient of the approach roadway, and the height of the driver's eyes above the roadway.

It is important that signal indications not be visible to drivers who are not controlled by those indications. For this reason, visors should be used around all signal lenses. Visors also reduce “sun phantom” which gives an unlighted lens the false appearance of being lighted when it is facing a low sun. The visor should be 1.27 millimeters thick and not less than 22.86 centimeters in length.

The visibility, location, and number of signal faces for each approach to an intersection or other signalized area should be as follows:

The control of the visibility and effectiveness of signal indications can be improved by shielding, long visors, and louvers, and by special optical design. Where streets intersect a small angle, these devices should be used to limit the visibiliVersion 0.0, Interim Edition

•

9-12

A minimum of two signal heads should be provided for through traffic. These faces should normally be continuously visible


•

•

•

•

•

from a point at least the distances shown in Table 9-3 in advance of and to the stop line. However, it is not usually desirable to allow motorists to see the indications of another traffic control signal which must be located less than the distances shown in Table 9-3 beyond a signal. On an approach that does not continue beyond the intersection, at least one (and preferably both) of the turning movements from that approach should have signal indications placed in accordance with this paragraph. The optical axis of signal indications should be aimed directly at the point on the approach which is at the distance shown in Table 9-3 from the stop line. If sight distance along an approach is less than given in Table 9-3, the indication should be aimed at the point on the approach where the indication will first become visible. Physical obstructions to signal visibility, such as tree limbs, parked vehicles, horizontal or vertical roadway curvature, buildings, etc., should be removed when practicable. Physical conditions may prevent drivers from having a continuous view of at least two signal indications for the distance stated in Table 9-3. In such cases an advance warning sign should be erected to warn approaching traffic. The sign should also be erected in advance of signals in rural areas, the first signal encountered when entering a municipality, or wherever signals may be unexpected. This sign may be supplemented by a Hazard Identification Beacon. Separate signal faces should be used when turning movements protected from conflicting movements are allowed by GREEN ARROWS. A single face is permissible for the control of traffic in a lane intended only for turning traffic. Two signal heads should be provided where more than one lane turns, or where the turning traffic is the major movement from the approach. An additional face should also be used when the required indication cannot be placed in an effective location. This signal face or faces should be in addition to the two signal faces required for through traffic. Signal indications for turning traffic should be adjusted to have as little visibility as practicable from the through traffic lanes. Where

•

the signal indications will be visible to through traffic, identification as a left (or right) turn signal should be placed near each such signal face. Except where physically impractical, at least one and preferably both of the signal faces should be located within the approved area shown in Figure 9-2. In only rare exceptions will the width of the intersecting streets or other conditions make it physically impracticable for the faces to be in that area. Boundaries of the approved area are defined by the following limits: - Two lines parallel to the center line of the intersected street, one 12 meters and the other 35 meters beyond the stop line. - Two lines intersecting at the center of the full width of the approach lanes at the stop line. Each line makes an angle of approximately 20” with the center of the approach extended, one to the right and the other to the left.

•

Where conditions require the nearest signal face to be more than 45 meters beyond the stop line. - Lense size should be 300 millimeters, and - A supplementary post-mounted “nearside” signal face should be placed on the right-hand side of the approach roadway as near as practicable to the stop line.

•

•

• •

9-13

Signal faces beyond the far-side curb of the intersected street should be as nearly straight ahead of the approaching driver as practicable, considering physical conditions and the means chosen for supporting the signal heads. A signal face may be located on the near side, immediately in advance of an intersection at the right side, on a median island, or at both locations. Such signals should be mounted on the top of the supporting post or by a short bracket attached to it. The signal face should be as near as practicable to the stop line. The lateral separation of the two signal faces should be not less that 2.5 meters measured horizontally between the centers of the faces. Signal faces for an approach should control traffic on all lanes of that approach, except Version 0.0, Interim Edition



9-14


•

•

• •

lanes intended only for “protected” turning or other special traffic movements. “Protected” movements are those which do not conflict with other movements occurring at the same time. Signal faces are not required for each lane of an approach to a signalized area. A signal face controlling a turning or special traffic movement should be located as near as practicable in line with the path of that movement. Such a signal face should be in a position where it will be readily visible to drivers it controls. Signal faces, in addition to those required elsewhere in this section, may be used. However, these signal faces should be used only when a study has shown the signals are needed to improve signal visibility in advance of or at the intersection. Left turn arrows should be used in signal faces located on the near right-hand side of an approach. Right turn arrows should not be used in signal faces in the following locations:

Glossary. A protected period is “leading” when it precedes the GREEN DISK indication on the same street. It is said to be “lagging” if it follows that GREEN DISK indication.

9.3.6 HEIGHT OF SIGNAL FACES A signal face is most visible when directly in the driver's line of sight. Intersection approach grades, lateral offset of the signal, vehicle design and driver position affect signal visibility. A signal should be as low as possible and yet give adequate vertical clearance over the roadway. Unless there are vertical clearance problems, all signal arrays should be vertical. The vertical array should be used for signals not over the roadway. The bottom of the housing of a signal face placed on a median island on the near side of an intersection approach should not be less than 1.25 meters and not more than 2.5 meters above the top of the median island. The bottom of the housing of signal face supported over a roadway should not be less than 5.5 meters nor more than 6.5 meters above the pavement below the signal.

- On the far left-hand side of an intersection. - On a signal mounted on a median island on the far side of an intersection. •

• •

Typical mast arm and bracket mountings of signals are shown in Figures 9-7 and 9-8.

At signalized locations between intersections, at least one signal face should be over and in line with the roadway of each approach. The other signal face should be mounted at the right-hand side of the roadway at a height of between 2.5 and 3 meters. On streets and highways having multi-lane approaches, an additional signal face should be installed at the left-hand side of the approach or on a median island of adequate width. In all other respects, the requirements for a signal between intersections should be the same as for a signal at an intersection. Pedestrian signal indications should be used where warranted as stated in Section 9.6. Standard approved signal head locations and indications for common and typical situations are shown in Figures 9-3 to 9-6. Other arrangements are possible within the general rules given herein. The meanings of the terms “permissive,” “protected,” and “protected/permissive” will be found in the

9.3.7 DESIGN AND LOCATION OF TRAFFIC CONTROL SIGNAL SUPPORTS AND CONTROLLER CABINETS FOR SAFETY Proper visibility of traffic signal faces is the primary consideration in the location of traffic signal supports. In the interest of safety, signal support should be places as far as practicable from the edge of the traveled way without adversely affecting the visibility of the signal. Supports for post-mounted signal heads and also signal heads at the side of a street should be placed not less than 0.5 meter back from the face of a curb. If there is no curb the supports and signal heads should be placed not less than 0.5 meter back from the edge of the shoulder.

9-15




9-16


9-17




9-18


9-19




9-20


9-21



9.4

Supports for mast arm pole-mounted signal heads should be placed in the most suitable roadway median facing the controlled approach

The need for traffic signals may be determined from the criteria set out below. These are a guide only and all other relevant factors should be taken in to account and proper engineering judgment exercised. These criteria alone should not be used to justify an installation. Their sole function is to separate locations where traffic signals are likely to be effective or ineffective.

A signal should not obstruct a crosswalk. Supports for post-mounted signal heads should be designed to readily break off, bend, or slip when hit by a vehicle, to minimize injury to the vehicle's occupants or damage to the vehicle. Where the speed of vehicles is less than 65 km/h and there is a vertical curb 25 cm or more in height, a “breakaway” support is not required. No part of the concrete base of a breakaway signal support should extend more than 10 cm above the ground level at any point.

To access priorities where all factors appear equal, cost-benefit techniques should be used. Various traffic models and computer simulation programs are available which permit detailed analysis of the benefits and effects of various traffic control options available at a site.

Vehicles should be protected from the base of a non-breakaway (rigid) signal pole such as is used to support a signal over the roadway. Guardrail or a suitable device to deflect or stop vehicles without serious injury to the occupants should be provided. However, this protection is not required if the support is located where it is unlikely to be hit by an out-of-control vehicle, or where the speed of vehicles is normally less than 65 km/h.

9.4.1 FACTORS TO BE CONSIDERED Several factors (warrants) should be considered before a decision is made whether or not to install a traffic control signal: •

Each controller cabinet should have a main door equipped with a keyed tumbler lock of the type in current use for this purpose in Abu Dhabi. An auxiliary door should be mounted on the main door. This door should be equipped with a lock operable by a different key. The door should give access to the manually flash, main power and controller power switches, and the manual control cord or phase change switches.

• • • • •

Overhead (mast arm) indications should be used on intersection approaches where: • • •

SIGNAL USE CRITERIA

•

More than 15 percent of the traffic is approaching at speeds in excess of 80 kph. On any approach where there are three or more approach lanes. Where physical conditions prevent drivers from having a continuous view of at least two signal indications.

The number of vehicles entering the intersection and major turning movements by these vehicles. The number of pedestrians crossing each approach to the intersection. The length of time traffic is congested at the proposed traffic control signal location. The number and type of accidents at the location. Physical features such as sight distances, grade, or width of street area. The interruption to the smooth flow of traffic a traffic control signal would cause. The possibility of using a less restrictive control device.

Traffic control signals should not be installed unless one or more of the signal criteria in the Manual are met. These criteria should be applied whether a pretimed or a traffic-actuated signal is being considered. If a decision is made to install a traffic control signal, future traffic needs should be considered in its design and installation.


9-22


Traffic studies of existing signalized intersections should be made at reasonable intervals. If a study indicates the criteria for existing traffic control signals are no longer met, the operation of these signals should be discontinued.

one period should be in the morning and the other in the afternoon or evening. However, the hours when traffic volumes are greatest will be the determining factor. Each vehicle should be recorded as a heavy truck, a passenger car or light truck, or a bus. The number of each of these three classes of vehicles entering the intersection during each 15 minutes period of each of the twohour periods should be recorded. (The form shown in Figure 9-9 can be used for this purpose by subdividing each group of three boxes and recording a class of vehicle in each subdivision.)

9.4.2 ENGINEERING DATA REQUIREMENTS A traffic engineering study should be made of an intersection or other problem location before a decision is made to (or not to) install a traffic control signal. The study should obtain at least the following data: •

•

•

•

•

When planning a signal installation, it is necessary to provide adequate roadway width to accommodate the volume of vehicles on each approach. Frequently, this can be accomplished by prohibiting parking for a sufficient distance back from the intersection to provide a right-turn lane or by widening the roadway. On each approach, at least two lanes for moving traffic, one for through traffic, and one for right or left turn traffic, should be provided unless it is physically impossible to do so.

On a day representative of average traffic volumes, the number of vehicles entering the intersection in each hours from each approach during the 7 consecutive hours of greatest total traffic. The vehicles turning right, going straight through and turning left should be separately recorded. (Typical traffic count forms for his purpose are illustrated in Figures 9-9 and 9-10.) The number of pedestrians crossing the intersection in each crosswalk during the same hours the vehicles are counted. (A typical pedestrian count form is illustrated in Figure 9-11.) A diagram of the intersection for at least 50 meters in each direction on each approach. (See Figure 9-12 for the information to be shown on this condition diagram.) A collision diagram showing the accidents during the last 12-month period for which accident data is available. (See Figure 9-13 for the data to be shown on this diagram.) The speed of vehicles on the intersection approaches not controlled by STOP signs. From this data the speed at or below which 85 percent of the vehicles were being driven can be calculated. (A form for recording vehicle speeds and calculating the 85-percentile speed is shown in Figure 9-14.)

Information obtained from the traffic engineering studies should be compared with the criteria set forth below to determine if signals are warranted.

9.4.3 CRITERION 1 — MINIMUM VEHICULAR VOLUME Principally the volume of traffic on the intersecting streets may indicate the desirability of a traffic control signal. This criterion is met under the following conditions: • • •

Data on the types of vehicles entering the intersection is not required but may be helpful in evaluating the problems at some intersections. Such a vehicle classification count should be made during two separate periods, each of two hours duration, when traffic volumes are highest. Preferably

• •

9-23

When large traffic volumes (more than 500) exist for each hour of any seven hours of an average day. When the volumes of traffic are at least equal to those in Table 9-4. An “average day” is any day, (other than a Friday) when the traffic volumes entering the intersection are representative of those normally and repeatedly found at that location. The volumes given in the last two columns of Table 9-4 must occur during the same hours. The higher volume minor street approach (fourth column, Table 9-4) may be one of the approaches during some of the eight hours



Abu Dhabi Municipality Traffic Survey Vehicle Volume Count Tally Sheet Date: __________

Day: ________ Time: ________ To: ________

Project Name: _____________________________ Location: _____________________

Rural: ________ City: ________

Intersection____________________________ and __________________________

Weather: ______________________ Road Condition: _____________________ Observers: _______________________

Right Through Through

ULeft Turn

U- Left Turn

U- Left Turn

Through Right From: ________ On: ________________

Figure 9-9 Vehicle Volume Count Field Data Form


9-24

Through

Right

From: ________ On: ________________

Right

U- Left Turn

From: ________ On: ________________

From: ________ On: ________________


9-25



Abu Dhabi Municipality Crosswalk Field Sheet Pedestrian Count

Project: _________

Adults

Children

Time: ________ To: ________ Date: ________ Observer: ____________

Adults

Adults

Children

Children

Location: _______________________

Adults

Children

Figure 9-11 Pedestrian Count Field Data Form


9-26

(Street Name)

(Street Name)


Building

Building

Building

Building

Building

Building

Building 3

3

3

3

3

3 No Parking

No Parking

2 2 1 1

3 2 3

3 2

2 1

2 3

1 2 2

No Parking

No Parking

15.0

3

3 3

3

3

3 Building

1.8

3.65

3.65

3.65

2.5

9.0

Building

0.2%

Building

Driveway Street Light Fire Hydrant Traffic Signal

1

2

3

Pedestrian Signal

Figure 9-12 Condition Diagram

9-27



COLLISION DIAGRAM Delma Street

Airport Road

Intersection: ______________________________________ and ___________________________________________ Period from: ______________________________________ to: ___________________________________________

Abu Dhabi City: ______________________________

AK Prepared by: ___________________________________________

2/8/1999

3/10/2001

22/6/1999

5/6/2000 20/12/2000

12/03/2001 10/9/2002

20/12/1999

15/2/1999 11/11/2000

Airport Road

NUMBER OF ACCIDENTS

12 3

Property Damage Only Injury or Fatal

Delma Street

Street Name

SYMBOLS

TYPES OF COLLISIONS

Moving Vehicle

Rear End

Backing Vehicle

Head On

1 - Time, Day, and Date

Non Involved Vehicle

Side Swipe

Pedestrian

Out of Control

2 - Weather and Road Surface, if Unusual Condition Existed

Parked Vehicle

15

Total Accidents

Left Turn

Fixed Object

Right Angle

Fatal Accident Injury Accident

Figure 9-13 Typical Collision Diagram


SHOW FOR EACH ACCIDENT

9-28

3 - Night, if Between Dusk and Dawn


9-29



Table 9-4 Minimum Vehicular Volumes for Criterion 1 Number of Lanes for Moving Traffic on Each Approach

Vehicles per Hour on Major Street (total of both approaches)

Vehicles per Hour on Higher-volume Minor Street Approach (one direction only)

Major Street

Minor Street

1

1

500

150

2 or more

1

600

150

2 or more

2 or more

600

200

1

2 or more

500

200

and the opposite approach during other hours.

•

This criterion is also met if the traffic volumes at the intersection are 70 percent or more of those shown in Table 9-4 when:

•

•

•

•

The speed of 15 percent of the traffic on the main street is 65 km/h or more, whether the intersection is in an urban area or rural area, or The intersection is in an area with frequent buildings ( a built-up area) in a city or village having a population of less than 10,000, and it is not near a larger city or village.

• •

When large traffic volumes exist on the major street for each hour of any 7 hours of an average day. The volumes of traffic are at least equal to those in Table 9-5. An “average day” is any day (other than a Friday) when the traffic volumes entering the intersection are representative of those normally and repeatedly found at that location. The volumes given in the last two columns of Table 9-5 must occur during the same hours. The higher volume minor street approach (fourth column, Table 9-5) may be one of the approaches during some of the 8 hours, and the opposite approach during other hours.

This criterion is also met if the traffic volumes at the intersection are 70 percent or more of those shown in Table 9-5 when:

9.4.4 CRITERION 2 — INTERRUPTION OF CONTINUOUS TRAFFIC

•

The desirability of a traffic control signal may be indicated by large numbers of vehicles on the major street. This may result in unreasonable delay and hazard to traffic on the intersecting street. This criterion is met under the following conditions:

•

The speed of 15 percent of the traffic on the main street in 65 km/h or more whether the intersection is in an urban area or a rural area, or The intersection is in an area with frequent buildings ( a built-up area) in a city or village

Table 9-5 Minimum Vehicular Volumes for Criterion 2 Number of Lanes for Moving Traffic on Each Approach


Vehicles per Hour on Higher-volume Minor Street Approach (one direction only)

Major Street

Minor Street

1

1

750

75

2 or more

1

900

75

2 or more

2 or more

900

100

1

2 or more

750

100


9-30


having a population of less than 10,000 and it is not near a larger city or village.

This criterion is also met if the vehicular or pedestrian traffic volumes at the intersection are 70 percent or more of those shown in Table 9-6 when:

A traffic control signal should not be installed under this criterion if its installation would seriously disrupt the flow of traffic in an existing or potential progressive signal system. (See Glossary for meaning of “progressive signal system.”)

• •

Figure 9-15 is an example of a traffic count made to determine if the minimum vehicular volumes for Criterion 2 were met.

Traffic control signals installed when this criterion is satisfied should be equipped with pedestrian signal indications.

9.4.5 CRITERION 3 — MINIMUM PEDESTRIAN VOLUME

If a signal is installed at an intersection more than 600 meters from the nearest signal, it is recommended to be traffic actuated with pedestrian pushbuttons at each end of each crosswalk across the major street.

A traffic control signal may be considered because many pedestrians wish to cross a busy street. Large volumes of traffic on a street may not permit pedestrians sufficient time to cross safely. This criterion may be met under the following conditions. • • •

• •

the speed of 15 percent of the traffic on the major street is 65 km/h or more, or the intersection is in an area with frequent buildings (a built-up area) in a city or village having a population of less than 10,000 and it is not near a larger city or village.

Traffic control signals may be installed when this criterion is met at locations between intersections, provided the crosswalk is 50 or more meters from another crosswalk or intersection. If the signal is within a progressive signal system, it should be coordinated with that system. In such cases, curbside parking should be prohibited for at least 30 meters before the crosswalk and 10 meters beyond it.

When large vehicle (more than 500) and pedestrian volumes (more than 150) exist for The vehicle and pedestrian volumes are at least equal to those in Table 9-6. An “average day” is any day (other than a Friday) when the traffic volumes entering the intersection are representative of those normally and repeatedly found at that location. The volumes given in the last two columns of Table 9-6 must occur during the same hours. One of the crosswalks may carry the greatest pedestrian volumes during some of the eight hours and the other crosswalk during other hours.

9.4.6 CRITERION 4 — SCHOOL CROSSING When children wish to cross a street, adequate gaps are needed between vehicles for the children to cross safely. However, adequate gaps may not occur frequently enough. This criterion is satisfied when the number of adequate gaps is less

Table 9-6 MInimum vehicular and Pedestrian Volumes for Criterion 3 Type of Roadway


Pedestrians per Hour Crossing the Major Street on the Crosswalk Having the Greatest Number of Pedestrians

No Pedestrian Refuge Island in the Street

600

150

Having a Raised Island at Least 1.25 m Wide in the Middle of the Approach

1000

150

9-31




9-32


than the number of minutes in the time period of the day during which children with to cross. Generally, this period should not be less than 15 minutes.

desirable to install a traffic control signal at an intersection between signals which are quite far apart. This will help to preserve the efficient grouping of vehicles and regulate vehicle speed.

When traffic control signals are installed where this criterion but no other criterion is satisfied, the following actions are also required:

The Progressive Movement criterion may be applicable when all three conditions exist.

•

•

•

•

•

Pedestrian signal indications should be provided for each crosswalk which has been designated for school children. Pedestrian signal indications may be provided for other crosswalks. A school crossing signal at an intersection should be fully traffic actuated. Signals in a progressive signal system may have pretimed control or, if traffic-actuated, should be coordinated with the system. At school crossings between intersections, the signal should be pedestrian-actuated. If within a progressive signal system, it should be coordinated with that system. At such signalized locations, parking should be prohibited for at least 30 meters in advance of the crosswalk and 10 meters beyond the crosswalk. A school crossing signal should not be installed within 150 meters of another traffic control signal, and should be located at least 30 meters and preferably further from the nearest intersection.

• •

The adjacent signals are more than 800 meters apart. A traffic engineering study shows that the vehicles do not remain in groups. Vehicle speeds are considerably above a safe speed.

A traffic control signal should normally not be installed if this criterion is satisfied when the resulting distance from that traffic signal to any adjacent signal would be less than 300m.

9.4.8 CRITERION 6 — ACCIDENT EXPERIENCE A traffic control signal may reduce the number of certain types of accidents occurring at an intersection, although the signal will cause more delay to drivers. It may also cause an increase in other types of accidents. The accident experience criterion is satisfied when all of the following conditions are met: •

9.4.7 CRITERION 5 — PROGRESSIVE MOVEMENT

•

When the indications of a traffic control signal change from red to green, the vehicles proceeding ahead on the green signal form a group. These vehicles usually stay in the group for 500 meters or more. The movement of traffic groups through a progressive signal system is more efficient than random movement of individual vehicles through the system.

• •

Progressive signal systems control the speed of traffic. A vehicle which is driven at a high rate of speed between signals would arrive at the second signal before the green indication is shown. If traffic control signals are far apart, the vehicles within a group disperse traffic. Thus, it may be

Other remedies such as improved signing, pavement markings and parking restrictions were tried but, no reduction in the number of accidents occurred. Five or more accidents involving pedestrians, or right angle or left turn vehicle collisions, each of which caused personal injury or considerable property damage were reported to the police within a 12-month period. The number of vehicles and pedestrians at the intersection is not less than 80 percent of the requirements in Criteria 1, 2, or 3. The installation of a signal will not seriously disrupt the smooth flow of traffic in a progressive signal system.

Any traffic control signal installed solely on the Accident Experience criterion should be traffic actuated. It may be semi traffic actuated when equipped with devices which provide proper

9-33



coordination (if installed at an intersection within a coordinated system). It normally should be fully traffic actuated if installed at an isolated intersection.

mining when this criterion is met. One is by using the major street and minor street traffic volumes. The other is by measuring the delay to minor street traffic.

Accident studies have shown the installation of a traffic control signal will significantly reduce the number of right angle collisions at an intersection. Right angle collisions are usually severe. A traffic control signal often will increase the number of rear-end collisions that are usually much less severe. Another type of accident which may be reduced by a traffic control signal is one involving pedestrians and vehicles.

The volume criterion may be applied by plotting on Figure 9-16 or 9-17 (whichever is appropriate): • •

When considering the removal of an existing traffic control signal, an analysis should be made of the accidents occurring at the intersection. The type and number of accidents that may occur if the signal were removed should be estimated. The vehicular and pedestrian volumes should also be considered. A thorough analysis of the existing and projected conditions at the intersection should indicate whether the signal should be removed or permitted to remain.

If the point plotted on the graph falls above the curve corresponding to the number of approach lanes, the criterion is met. This criterion also applies when the following conditions are met: •

9.4.9 CRITERION 7 — COMBINATION OF CRITERIA

During the peak traffic period traffic on a side street (controlled by a STOP sign) experiences a total delay per hour of: - Four or more vehicle hours for a singlelane approach, or - Five or more vehicle hours for a two-lane approach.

A traffic control signal may occasionally be justified when no single criterion is met. When at least 80 percent of the traffic volume required by paragraph No. 1or 2 (as appropriate) of two or more of the first three Criteria (1, 2, and 3) are met, a traffic control signal may be justified.

•

Before a signal is installed under this criterion, there should be adequate trial of other remedies such as improved signing, pavement markings, and parking restrictions. A signal should be installed only if other remedies do not correct the problems.

The volume on the side street approach during the same hours is - One hundred or more vehicles per hour for a single-lane approach or - One hundred and fifty vehicles per hour for a two-lane approach.

•

9.4.10 CRITERION 8 — SHORT PEAK PERIOD TRAFFIC VOLUME CRITERION

The total traffic entering the intersection on all approaches during the same hours is - Eight hundred or more vehicles per hour for intersections with four or more approaches, or - Six hundred and fifty vehicles per hour for intersections with three approaches.

A traffic control signal may be indicated where, during only 1 or more hours of an average day, minor street traffic experiences unreasonable delay or hazard. There are two methods of deter-


The total traffic volume on the major street and Τhe number of vehicles entering the intersection on the higher volume minor street approach. (Note: Figure 9-17 is to be used in communities with a population of less than 10,000, or the speed limit on the major street is 65 km/h or more.)

9-34

Lanes per Approach:

600

One on both streets. 500

Two or more on one street and one on the other street.

400

Two or more on both streets. 300 200

* *

100 400

*

800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 Major Street — Total of Both Approaches — VPH 150 VPH applies as the lower threshold for a minor-street approach with two or more lanes and 100 VPH applies as the lower threshold volume for a minor-street approach with one lane. 500

600

700

Figure 9-16 Peak Hour Volume Criteria

Lanes per Approach: Minor Street — High-volume Approach — VPH

Minor Street — High-volume Approach — VPH


One on both streets. Two or more on one street and one on the other street.

400 300

Two or more on both streets.

200

**

100 300

400

500 600 700 800 900 1000 1100 1200 1300 Major Street — Total of Both Approaches — VPH

VPH applies as the lower threshold for a minor-street * 100 approach with two or more lanes and 75 VPH applies as the lower threshold volume for a minor-street approach with one lane. Figure 9-17 Peak Hour Volume Criteria (less than 10,000 population or above 65 km/h)

9-35



9.4.11 CRITERION 9 — ESTIMATE OF TRAFFIC ON STREET TO BE CONSTRUCTED

9.4.12 SELECTION OF PRETIMED OR TRAFFIC-ACTUATED CONTROL

This criterion may be used only to evaluate the need for a traffic signal at a newly constructed intersection, created or revised by a highway construction project, or at the driveway of a new commercial or residential development.

Pretimed traffic control signals are generally the most appropriate type for the following conditions:

The anticipated traffic volume is estimated as of the date the intersection is opened to traffic, or:

•

•

Unless an intersection is or will be in a coordinated signal system, traffic-actuated signals may be used in place of pretimed signals. Traffic-actuated signals are also appropriate for the following conditions:

•

•

Within 2 years from the date of opening of a highway construction project, or Within 6 months from the date of the opening of a new commercial or residential development.

•

This criterion is met when the estimated average daily traffic volume on the major street and on the higher volume minor street or driveway approach to the intersection equals or exceeds the volumes of traffic shown in Table 9-7.

•

This criterion is also met if the traffic volumes are estimated to be 70 percent or more of those shown in the Table 9-7 when: •

•

• •

Τhe speed of 15 percent of the traffic on the main street is 65 km/h or more, whether the intersection is in an urban area or a rural area, or The intersection is in an area with frequent buildings (a built-up area) in a city or village having a population of less than 10,000, and it is not near a larger city or village.

•

A repeated, predictable traffic volume pattern. An intersection in the built-up area of a city or village.

When the volume of traffic low, changes frequently through the day, or is greater first on one approach and then on others. When the side street vehicles are numerous only during a few peak hours per day, and those are the only hours when considerable delay is experienced on the side street. When only the pedestrian or accident criterion is used. When the signal will not be installed at an intersection. When the signal will be at an isolated location, that is two kilometers from the nearest signalized intersection.

Table 9-7 Minimum Vehicular Volumes for Criterion 9 Number of Lanes for Moving Traffic on Average Daily Traffic Each Approach Major Street Minor Street Major Street Minor Street (both approaches) (one approach) 1 1 10000 3000 2 or more 1 12000 3000 2 or more 2 or more 12000 4000 1 2 or more 10000 4000 1 1 15000 1500 2 or more 1 18000 1500 2 or more 2 or more 18000 2000 1 2 or more 15000 2000


9-36


9.4.13 PEDESTRIAN ACTUATION OF TRAFFIC CONTROL SIGNALS

long. The exclusive function of the yellow change interval should be to warn traffic of an impending change in the right-of-way assignment. The change intervals for a particular intersection should be selected on the basis of its physical and traffic characteristics by using Table 9-8 or the formula:

Pedestrian detectors (usually pushbutton switches at the ends of crosswalks) should be installed with a traffic-actuated traffic control signal when pedestrians would have to wait an unreasonable length of time for a vehicle actuation to give them an opportunity to cross.

0.91V _______ Vehicle Change Interval = T + 6.56A + 0.644G

Pedestrian detectors should be installed with a traffic-actuated traffic control signal if pedestrians would not have sufficient time to cross the intersection during a green signal indication for vehicles.

Where: A = Max. deceleration rate (m/s2), typically 3.048. T = Reaction time, typically one second. G = Gradient of approach. V = Speed of vehicle (km/h).

9.4.14 SIGNAL CRITERIA ANALYSIS FORM

The vehicle red clearance interval should not exceed nine seconds. A vehicle may enter an intersection immediately before the end of the yellow change interval. It must be allowed to leave the intersection before conflicting traffic enters. The clearance intervals for a particular intersection should be selected on the basis of its physical and traffic characteristics for the initial timing of the signal controller by using Table 9-9 or the formula:

Figure 9-18 shows a convenient form used to summarize the data, which determine if one or more of the traffic signal criteria are met.

9.5

TRAFFIC CONTROL SIGNAL OPERATION

9.5.1 VEHICLE CHANGE AND CLEARANCE INTERVALS

T (sec.) = The exclusive function of the steady yellow interval is to warn traffic that a change in the right-ofway assignment will occur. The vehicle change interval should be long enough to allow drivers approaching the indication at a legal speed to stop before entering the intersection.

3.6 (W + C + L) ______________ V

Where: W = Street width in meters. C = Distance from stop line to near side of cross street. L = Length of the vehicle. V = Speed of vehicle (km/h).

A vehicle change interval should be followed by a short red clearance interval to allow vehicles which have entered the intersection to leave before conflicting vehicle movements enter it.

Change and clearance intervals should be provided between the termination of a GREEN ARROW indication and the showing of a GREEN indication to any conflicting traffic movement. The change interval is shown by a AMBER ARROW indication. This may be followed by a RED indication if that movement is no longer permitted.

The length of vehicle change and clearance intervals depends on the speed and type of approaching traffic, the width of the intersected street, and the gradient (negative or positive) of the approach. The vehicle change interval should not be less than three seconds nor more than seven seconds. Drivers will violate a yellow interval which is too

9-37



Traffic Signal Criteria Analysis Form City: Abu Dhabi

Route:

Calc: AK

Date: 17 Feb. 2003

Chk: AHS

Date: 19 Feb. 2003

Major St.: Khaleej Al Arabi

Critical Approach Speed: 65 km/h

Lanes: 3

Minor St.: Delma

Critical Approach Speed: 65 km/h

Lanes: 3

70% Vol. Critical Speed of Major Street Traffic > 65 Km/H . . . . . . . . . . . . . . . . . In Built-Up Area or Isolated Community of < 10,000 Pop. . . . . . . . . .

X 70%

Applicable Minimum Volume Requirements:

100%

X X

100% Vol.

Yes

No

Yes

No

Criterion 1 — Minimum Vehicular Volume 100% Satisfied

Minimum Requirements (80% Shown in Brackets) 100% Approach Lanes Both Approaches Major Street Highest Approach Minor Street

70%

100%

350 (280) 105 (84)

600 (480) 200 160)

1 500 (400) 150 (120)

Yes

80% Satisfied

Yes

X No X No

Hour

70%

1600 1700 1500 1300 1200 700 1400 1100

2 or More 420 (336) 140 (112)

628

619

71

52

594 558 532 62

39

70

511

507 484

46

49

79

Note: Heavier of Left-Turn Movement From Major Street Included When LT -Phasing is Proposed.

Criterion 2 — Interruption of Continuous Traffic 100% Satisfied

Minimum Requirements (80% Shown in Brackets) 100% Approach Lanes Both Approaches Major Street Highest Approach Minor Street

70%

100%

525 (420) 53 (42)

900 (720) 100 (80)

1 750 (600) 75 (60)

80% Satisfied

70%

X No

Yes

X Yes

No

Hour 1600 1700 1500 1200 700 1400 1100 900

2 or More 630 (504) 70 (56)

628

619

71

52

594 532 63

70

511

507 484 455

46

49

79

108

Note: Heavier of Left-Turn Movement From Major Street Included When LT -Phasing is Proposed.

Criterion 3 — Minimum Pedestrian Traffic Minimum Requirements (80% Shown in Brackets) Median

100%

600 (480) Raised 10 cm 1000 Volume Median (800) Pedestrians on Highest-Volume X-Walk Crossing 150 Major Street (120) If Midblock Signal Proposed Minimum Requirement Both Approaches Major Street

No Median

100% Satisfied

Yes

80% Satisfied

Yes Hour

70% 420 (336) 700 (560) 105 (84)

50 Meters

Distance to Nearest Established X-Walk N/E __________ M

Criterion 4 — School Crossings

Not Applicable See School Crossings Warrant Sheet

9-38

Fulfilled

S/W __________ M

Figure 9-18 (page 1 of 2) Completed Traffic Signal Criteria Analysis Form


X No X No

Yes

X

No


X X X

X

ü

X X

X X

X X

ü ü ü ü

X

X

ü

X

X

Figure 9-18 (page 2 of 2) Completed Traffic Signal Criteria Analysis Form

9-39



Table 9-8 Vehicle Change Interval (seconds) 85th Percentile Approach Speed (km/h) 30 40 50 60 70 80 90 100 120 Notes:

Gradient on Approach -8% 3.0 3.5 4.1 4.7 5.3 5.9 6.5 7.0 7.0c

-6% 3.0 3.3 3.8 4.4 5.0 5.5 6.1 6.6 7.0b

-4% 3.0 3.1 3.6 4.1 4.7 5.2 5.7 6.2 7.0a

-2% 3.0 3.0 3.4 3.9 4.4 4.9 5.4 5.9 6.8

0 3.0 3.0 3.3 3.7 4.2 4.6 5.1 5.6 6.5

+2% 3.0 3.0 3.1 3.6 4.0 4.4 4.8 5.3 6.1

+4% 3.0 3.0 3.0 3.4 3.8 4.2 4.6 5.0 5.8

+6% 3.0 3.0 3.0 3.3 3.7 4.1 4.4 4.8 5.6

+8% 3.0 3.0 3.0 3.2 3.5 3.9 4.3 4.6 5.3

a. Add 0.3 seconds to clearance interval shown in last column of Table 9-9 (when approach gradient is -4%). b. Add 0.8 seconds to clearance interval shown in last column of Table 9-9 (when approach gradient is -6%). c. Add 1.4 seconds to clearance interval shown in last column of Table 9-9 (when approach gradient is -8%). After the signal is functioning, it should be adjusted for actual local operating conditions. The length of the interval can frequently be shorter than initially calculated.

Cross Street Width (meters) 9 12 15 18 21 25 28 31 34 37 40 43 46 55 60

Notes:

30 2.5 2.9 3.2 3.6 4.0 4.4 4.8 5.2 5.5 5.9 6.2 6.6 7.0 8.0 8.6

40 1.9 2.2 2.4 2.7 3.0 3.3 3.6 3.8 4.1 4.4 4.7 5.0 5.2 6.0 6.5

Table 9-9 Vehicle Red Clearance Interval (seconds) 85th Percentile Vehicle Approach Speed km/h 50 60 70 80 90 100 1.5 1.3 1.1 0.9 0.8 0.8 1.7 1.4 1.2 1.1 1.0 0.9 1.9 1.6 1.4 1.2 1.1 1.0 2.2 1.8 1.5 1.4 1.2 1.1 2.4 2.0 1.7 1.5 1.3 1.2 2.7 2.2 1.9 1.7 1.5 1.3 2.9 2.4 2.1 1.8 1.6 1.4 3.1 2.6 2.2 1.9 1.7 1.5 3.3 2.8 2.4 2.1 1.8 1.7 3.5 2.9 2.5 2.2 2.0 1.8 3.7 3.1 2.7 2.3 2.1 1.9 4.0 3.3 2.8 2.5 2.2 2.0 4.2 3.5 3.0 2.6 2.3 2.1 4.8 4.0 3.4 3.0 2.7 2.4 5.2 4.3 3.7 3.2 2.9 2.6

Add the following values to the Vehicle Clearance Intervals when the approach gradient is: -4% add 0.3 seconds -6% add 0.8 seconds -8% add 1.4 seconds


9-40

110 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.2 2.4

120 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 2.0 2.2


9.5.2 PREVENTION OF UNEXPECTED TRAFFIC CONFLICTS

A pretimed signal controller or system generally does not change the sequence in which indications or phases occur. However, in traffic-actuated controllers and traffic-adjusted signal systems, both the sequence and timing of intervals and phases can change each cycle. Whether or not the sequences change frequently, they must be planned and controlled to prevent unsafe and conflicting indications and movements.

Signal indications, allowing unexpected crossing or merging of the paths of vehicles with the paths of other vehicles and pedestrians, should not be given except when all of the following three conditions exist: • • •

Every controller or control system should be designed and operated for safe and efficient functioning. In the normal operation of a traffic control signal, the indications on a specific signal face should be followed by one of the approved indications or combinations of indications given in Table 9-1. No unauthorized “following” indications may be shown. The authorized indication progression in the case where the operation of a traffic control signal is preempted by a train or emergency vehicle may be taken from either Table 9-1 or Table 9-2.

The crossing or merging involves only slight hazard, and Serious traffic delays can be materially reduced. Drivers and pedestrians making the conflicting movements are effectively warned of the conflicts.

Warning may be given by signs or the use of an appropriate traffic signal indication. A LEFT GREEN ARROW signal indication should not be shown when drivers obeying it would intersect the path of pedestrians crossing in response to a walk indication.

A signal installation should comply with the following requirements: •

9.5.3 PROTECTIVE FAIL-SAFE CIRCUITRY

•

Traffic signal controllers installed shall, through internal or external electrical circuitry, determine if green signal indications are being given to conflicting traffic movements. If such indications are being given, the signal should immediately be transferred to the flashing mode described in paragraph 9.05 F7. The signal should stay in this mode until the fault is corrected, and the signal is manually restored to normal operation. An alarm should also be generated at the traffic control center, where applicable, to alert the operator of such conflict.

•

•

9.5.4 SEQUENCE OF TRAFFIC CONTROL SIGNAL INDICATIONS (OPERATING PLANS)

•

The safe and efficient operation of a signalized intersection is dependent upon providing the best sequence and timing of signal intervals and phases.

9-41

An arrow indication should never direct vehicles across the path of pedestrians who have a Walk indication. When a green vehicular indication or a pedestrian Walk indication is terminated, it should be followed by a change and a clearance interval. If a GREEN DISK indication is to continue when a GREEN ARROW indication begins, (called a lagging left turn), opposing or conflicting vehicular movements should first be stopped. This should be done by displaying a yellow change indication followed by a red clearance indication for the conflicting movements. The GREEN ARROW indication may be shown. A signal indication sequence may allow a left turn to be made only on GREEN ARROW. Such a sequence should be used only when left turning vehicles have a lane separate from, and in addition to, lanes for through traffic. “Protected” turning movements are allowed by GREEN ARROW indications shown when other traffic movements do not conflict with the turning movements. It is easier for Version 0.0, Interim Edition


drivers to turn left when they are protected by the signal from conflicting movements than when they are not protected. However, protected turns frequently reduce the efficiency and capacity of an intersection. Therefore, signal-operating plans should provide for protected turning movements typically at intersections where the left turn volume is large or where left turn accidents have been frequent.

•

Many sequences of signal phases are possible. The sequence of phases sometimes affects the sequence of indications within a phase. The most commonly used sequences of signal phases and indications (operating plans) are given in the following paragraphs. If an engineering study shows a different phase sequence is desirable, that sequence should comply with all standards herein. • •

•

•

The standard four phase traffic signal is shown in Figure 9-19. The standard sequence of traffic signal indications and phases is shown in Figure 9-20. Figure 9-20 also shows the standard numbering for traffic signal indications. It should be used whenever practicable. It is particularly applicable to the intersection of two streets where all drivers who wish to turn left can do so within two signal cycles. The standard sequence which includes pedestrian signal indications is shown in Figure 9-21. A left turn movement may be “permissive,” “protected/permissive,” or “protected/prohibited.” A permissive left turn is one which may be made whenever a GREEN DISK is displayed (unless prohibited by a regulatory sign). In a protected/permissive left turn, the GREEN ARROW indication is displayed with the GREEN DISK indication. This tells motorists no oncoming traffic from the opposite direction (or other movements) will conflict with turning traffic during the GREEN ARROW left turn phase. However, during the display of the GREEN DISK indication alone without the GREEN ARROW, vehicles turning left must yield the right-of-way to vehicles entering from the opposite approach on the GREEN indication. The term “protected/prohibited” also means no movements will conflict with turning traffic during the


•

•

•

GREEN ARROW phase. However, left turns are prohibited when the GREEN ARROW indication is not being shown to that approach. The GREEN ARROW indication may be displayed with or independent of the GREEN DISK indication for a protected/permissive left turn. A left turn movement may be allowed to take place throughout the green phase (permissive phasing), at the beginning or at the end of the green phase. When allowed at the beginning of the green phase, it is called a leading left turn interval. When allowed at the end of the green phase it is called a lagging left interval. A leading left turn is usually preferable to a lagging left turn because the risk of accidents is less when the turn is leading. Before a leading left turn begins, all traffic is stopped because the cross street green phase has terminated. Therefore, there are no conflicting movements, and the likelihood of accidents involving the vehicles turning on the leading GREEN ARROW decreases. A lagging left turn from only one approach usually is accompanied by a GREEN DISK on the same approach. Traffic on the opposite approach, (which has a RED DISK indication) may not stop because it is watching other traffic. Generally, a lagging left turn should be simultaneous on both opposite approaches with both through movements being stopped. A left turn movement from a street may be allowed from only one of its approaches to the intersection or from opposite approaches simultaneously. The latter is called a twodirection simultaneous left turn. Straight through and right turning vehicles should be prohibited from entering the intersection at this time. When Walk and Don't Walk indications are used, the GREEN ARROW interval must be coordinated with the pedestrian indications (see Section 9.5.2). The signal operating plans for several typical intersection designs are illustrated in the following figures: - Figure 9-22: Leading Protected/Permissive Left Turn From One/Approach - Figure 9-23: Permissive Left Turn on

9-42


GREEN DISK from Opposite Approaches - Figure 9-24: Leading Protected/Permissive Left Turn from Opposite Approaches - Figure 9-25: Leading Protected/Prohibited Left Turn from One Approach Intersection with One-Way Street - Figure 9-26: Intersection of Two Divided Streets with Service Roads - Figure 9-27: Intersection of Two Divided Highways Having Left-Turn Bays in the Median - Figure 9-28: “T” Intersection with a Service Road Along the Principal Street - Figure 9-29: “T” Intersection with a LeftTurn Bay and Continuous Traffic on the Principal Street •

•

•

•

north to east and from south to west may occur only on the GREEN ARROW indication (protected/prohibited left turns). Left turns from east to south and from west to north may occur both on the appropriate GREEN ARROW and on the GREEN DISK indication on those approaches (protected/permissive left turns). Some of the explanatory notes in Figure 9-31B also apply to Figure 9-30. - Figure 9-30B is a diagram of the eight phases (each interval is considered to be a phase) in the signal sequence. Through and left turn movements are given separate phases. It is assumed right turns may be made on the GREEN DISK indication. Figure 9-31 has two parts.

Right turns normally involve considerably less potential conflict than left turns. Also, right turn intervals seldom are needed. The same general principles may be applied to right turns as to left turns in those cases where a right turn interval is required. Signal controllers and systems should be designed to provide interval and phase sequences which meet the requirements of this section. The newest types of controllers and systems, where most equipment use digital technology, have great flexibility in the timing and sequence of intervals and phases. In the case of pretimed equipment, operation may be specified by detailing all indications in proper sequence. Figure 9-20 illustrates one manner in which the sequence of signal phases, intervals and indications may be shown. This method is particularly satisfactory for pretimed signals in which the sequence of phases does not change. Figures 9-30A and 9-30B illustrate a manner in which the desired operation of a trafficactuated signal may be shown. Modern traffic-actuated controllers may be designed and operated by traffic demand to vary the lengths of intervals and change the sequences in which the intervals occur.

- Part A is a table showing for each phase the other phases (non conflicting phases) which could simultaneously be shown with it and the phases (called conflicting phases) which would have movements in conflict with the phase having the green indication. More than one phase (for example Phases 1 and 5, or 3 and 8) may occur simultaneously, if the appropriate detectors are actuated. However, phases occurring simultaneously must be on the same side of the “barrier line.” Also, no more than two phases per ring may occur simultaneously. Exceptions to these limitations occur when “overlapping” phases are present, but the complexity of this phasing requires more space than is available in this Manual. The terms “ring” and “barrier” come from the characteristics of the solid-state circuitry used in these controllers. - Part B is a table, with explanatory notes, showing the signal indications used in the change and clearance intervals following each phase. The signalization of the intersection of the ramps and the crossroad at a diamond interchange is a special case. Several standard types of phase sequences are used. Some of the most useful of these are shown in Figures 9-32 to 9-35. Traffic

- Figure 9-30A shows a simple intersection of two streets, each with a curbed median and left-turn bays. Vehicle detector loops and signal faces are shown, as well as pedestrian signal faces. Left turns from 9-43



Indication in All Signal Faces Sequence of Signal Indications Using a Pretimed Controller

Figure 9-19 Standard Four-Phase Traffic Signal — Without Pedestrian Signals


9-44


V6 N

V2 V11 Cross street

V1

V4 V9

V12

V7

V8

V10 V5

Standard signal numbering sequence is shown.

V3

Indication in All Signal Faces Sequence of Signal Indications Using a Pretimed Controller

Figure 9-20 Signal Operating Plan No. 1 — Standard Signal Operating Plan — Without Pedestrian Signals

9-45



V6 N

P1 P8 V11

V1

V2

P2 V7

V8 P6

P7 V9 The standard numbering system for pedestrian indications is shown in this figure.

V12 P5

V10 V5 P4

P3 V3

Indicates flashing signal. Sequence of Signal Indications Using a Pretimed Controller

W

W

W

W

Figure 9-21 Signal Operating Plan No. 2 — Standard Signal Operating Plan — With Pedestrian Signals


9-46


Indications on Each Signal Face


W

W

W

W

W

Figure 9-22 Signal Operating Plan No. 3 — Leading Protected/Permissive Left Turn From One Approach — With Pedestrian Signals

9-47



Indicates flashing signal.

Sequence of Signal Indications Using a Pretimed Controller

W

W

W

W

Figure 9-23 Signal Operating Plan No. 4 — Permissive Left Turn On Green Disk From Opposite Approaches — With Pedestrian Signals


9-48



W

W

W

W

Figure 9-24 Signal Operating Plan No. 5 — Leading Protected/Permissive Left Turn From Opposite Approaches — With Pedestrian Signals

9-49



Indicates flashing signal.


W

W

W

W

W

W

Figure 9-25 Signal Operating Plan No. 6 — Leading Protected/Prohibited Left Turn From One Approach Intersection With One-Way Street — With Pedestrian Signals


9-50



Figure 9-26 Signal Operating Plan No. 7 — Intersection of Two Divided Streets With Service Roads — Stop or Signal Control on the Service Roads — Without Pedestrian Signals

9-51




W

W

W W

Figure 9-27 Signal Operating Plan No. 8 — Leading Protected/Prohibited Left Turn From Two Approaches — Leading Protected/Permissive Left Turn From Two Other Approaches — Intersection of Two Divided Streets With Left-Turn Bays — With Pedestrian Signals


9-52


V11 V10 V10

V2

V1

V9 V5

V7

V6

V8

V12

V13

V14

V4

V3


Figure 9-28 Signal Operating Plan No. 9 — “T” Intersection With a One-Way Service Road Along the Principal Street — Without Pedestrian Signals

9-53



Indication in All Signal Faces


Figure 9-29 Signal Operating Plan No. 10 — “T” Intersection With Left-Turn Bay — Continuous Traffic on the Principal Street


9-54


D7 D8

V10

D6 P1

P2 V2

V1

V16

V3

V4

D13 D14

V15 D12 V14

V11

D9 D11

V9

D10 V13 All detectors call and extend their associated phases. Detectors D2 and D3 are calling detectors only and are disconnected during phase 2. Detectors D1, D6, D9, and D12 operate in the nonlocking mode. All other detectors operate in the locking mode.

V8

V6

V12

V7

P3

P4 D1

V5 D2 D3

D5 D4

Figure 9-30A Intersection Plan — Traffic-Actuated Signal With Pedestrian Signals

Figure 9-30B Movements During Each of the Phases

9-55



Phase Having Nonconflicting Phase Allowed Green to Time Concurrently

Phases in Conflict with Phase Having Green

1

5 or 6

2, 3, 4, 7, 8

2

5 or 6

1, 3, 4, 7, 8

3

7 or 8

1, 2, 4, 5, 6

4

7 or 8

1, 2, 3, 5, 6

5

1 or 2

3, 4, 6, 7, 8

6

1 or 2

3, 4, 5, 7, 8

7

3 or 4

1, 2, 5, 6, 8

8

3 or 4

1, 2, 5, 6, 7

Figure 9-31A Table of Conflicting and Nonconflicting Phases


9-56


9-57



Phase 1

Phase 2

Phase 3

Notes: May be either pretimed, if it can be included in a coordinated system, or may be traffic actuated. Is not recommended where vehicles turning left off of ramps or frontage roads are numerous. Is generally not suitable for an urban location.

Figure 9-32 Three-Phase, Lead-Lag Diamond Interchange Ramp Signal Sequence


9-58


Phase 2

Phase 1

Phase 3

Phase 4

Notes: Very good when there is much ramp traffic and more on one ramp than the other. Minimizes the need for provision for vehicles stopped on the cross street awaiting an opportunity to turn left. Must be pretimed. Is not as efficient as the four-phase, two-overlap sequence. Figure 9-33 Four-Phase Diamond Interchange Ramp Signal Sequence

9-59



Phase 1 Overlap

Phase 2

Phase 1

Phase 3

Phase 3 Overlap

Phase 4

Notes: Must be pretimed. Makes efficient use of green time. More efficient than any other system. Is especially effective at interchanges where the spacing between ramp terminals is short and left-turn storage is limited. Figure 9-34 Four-Phase, Two-Overlap Diamond Interchange Ramp Signal System


9-60


Phase 1

Phase 2

Phase 3

Notes: Has high traffic capacity when there is a large number of cross-street vehicles and relatively few left turns. Can use a shorter cycle than other phasing. Especially good when ramps are 120 m to 150 m apart along the main road. The phasing can readily be produced by a standard three-phase, traffic-actuated controller.

Figure 9-35 Three-Phase, Lag-Lag Diamond Interchange Ramp Signal System

9-61



estimates should be made prior to signalization, and the most appropriate phase sequence should be adopted initially. Studies should be made after signalization, and one of the other phase sequences should be used if better results could be obtained with it.

ers literature, and should be consulted if a coordinated network is anticipated.

9.5.6 FLASHING OPERATION OF TRAFFIC CONTROL SIGNALS All traffic control signal installations should have electrical mechanisms which will flash the signal indications when activated by a manual or automatic switch. It should be possible to remove the signal timer without affecting the flashing of the indications. During flashing operation, the indications should be flashed at a rate of not less than one-half nor more than two-thirds of the total flash cycle.

9.5.5 COORDINATION OF TRAFFIC CONTROL SIGNALS Both pretimed and traffic-actuated signals within 800 meters of one another along a major route or in a network of major routes should normally be operated in coordination to minimize unnecessary delay and accidents. Coordination may be accomplished by wires between the signal controllers in the system, with one controller (or a central master controller) designed to send impulses at intervals to regulate the operation of the other controllers. As a temporary measure, pretimed signals may be coordinated by using a common cycle length and setting the time relationships (offsets) by stopwatch. Coordination usually cannot be maintained across boundaries between signal systems which operate on different cycle lengths.

Automatic changes (by time clock or remote control) from flashing to stop-and-go operation should be made when a green indication is shown in both direction on the major street. Where there is no such green indication for both directions, the change should be made at the beginning of the green interval for the greatest traffic movement on the major street. Automatic changes from stop-and-go to flashing operation should be made at the end of the period during which the red indication is shown in both directions on the major street.

A time-base coordination unit at each controller may be used for coordinating traffic control signals. No wires are needed between controllers. The time-base coordinator is essentially an accurate and stable clock which may be independent of the power mains. Each time-base unit can be set to regulate the cycle, splits, and offset of its associated controller. Because of the timing stability of the time-base coordinator, the time relationships of the signals in the system do not change over long periods of time. Time-based coordinators are available which can be programmed for a time period of a week or a full year.

The operation of the manual “flash” switch or the “fail-safe” conflict monitor (see Section 9.5.3), should cause the immediate change from stopand-go to flashing operation. Restoring the manual “flash” switch to the “automatic” position or operation of the conflict monitor reset switch should cause the immediate change from flashing to stop-and-go operation. A short, steady all-red interval should be given to all minor street approaches before changing from flashing red to green on a minor approach.

Until recently, coordination was usually accomplished by a master controller that supervised the operation of local controllers at individual intersections. The availability of computerized equipment has made possible more complex and efficient coordinated control of signal networks. Much useful information on this subject is available in periodicals, handbooks, and manufactur-


There is usually period of four or more consecutive hours of the night when the volume of traffic is much less than in the day-time. During such periods, when traffic is less than 50 percent of the volume criteria in Section 9.4 of this chapter (or less than 120 vehicles per hour), a pretimed signal may be placed on flashing operation. Trafficactuated signals should normally not be placed

9-62


•

on flashing operation during such times of lower traffic. At such times, a properly adjusted and maintained traffic-actuated signal will not cause unnecessary delay to traffic and will provide safer traffic movement than would flashing operation. In Abu Dhabi, placing a signal on flashing mode requires a prior authorization of the Department.

•

•

When the Department approves that a traffic control signal be placed on flashing operation mode, the following signal indications should normally be displayed: • •

A GREEN ARROW indication used alone to permit a continuous movement should be constantly illuminated when other indications in the signal installation are flashed.

Flashing yellow in all indications facing traffic on the main street or highway. Flashing red in all indications facing traffic on the minor or cross streets. At some intersections, traffic volumes on the main and cross streets may be nearly equal and accidents may be displayed in the indications facing main street traffic and also those facing cross street traffic.

9.5.8 CONTROL PREEMPTION BY PRIORITY TRAFFIC Special classes of traffic (emergency vehicles, trains, transit vehicles, and certain official vehicles) may require priority over other traffic. Equipment is available to allow such traffic to modify the timing, sequence, or display of traffic signal indications. Change and clearance intervals and displays should be provided when a priority vehicle causes a change in the normal timing, sequence or signal display. Priority control may be established over one signal or over all or parts of an entire signal system.

A traffic control signal indication that is sufficiently bright to be effective in the day time may be too bright at night. Therefore, except in urban areas with bright surroundings and on high speed rural roads, indications may be automatically dimmed at night. The dimming device should reduce the light output of each signal indication proportionally as the ambient light level decreases. The reduction should be not more that 50 percent and not less than 30 percent of the light output at full rated voltage.

The indications of signals under priority control should allow traffic to continue to move as normally as possible without delay or hazard to priority vehicles. Long all-red or flashing signal sequences should not be used.

9.5.7 CONTINUITY OF OPERATION OF TRAFFIC CONTROL SIGNALS

9.5.9 MAINTENANCE OF TRAFFIC CONTROL SIGNALS

A traffic control signal installation, except as provided below, should at all times be operated either as a stop-and-go device or as flashing device. •

When a traffic control signal installation is being operated as a stop-and-go device, at least one indication in each signal face should be illuminated. When a traffic control signal installation is being operated as a flashing device, at least one indication in each signal face should be flashed. The indication of traffic control signals for emergency vehicle entrances do not have to be steadily illuminated or flashed except when those signals are activated.

Proper and reliable operation of traffic control signals involves regular and emergency maintenance. This includes maintenance to reduce the likelihood of the failure of any signal component and prompt repair or replacement of malfunctioning signal units.

Before being placed in operation, during major reconstruction, or a seasonal shutdown, a signal may not be operating. In such cases, the signal faces should be covered, turned away from the street, or removed to clearly indicate the signal is not in operation.

Traffic signal equipment occasionally fails to function properly. If a breakdown or failure of the

9-63



9.5.10 VEHICLE SENSORS

equipment occurs, control should be reestablished in one of the following ways: • • •

Traffic-actuated signal control is generally more efficient than pretimed control at intersections which are not part of a signal system. However, the efficiency of traffic-actuated signal control is greatly affected by the type, placement, and maintenance of the vehicle detectors used with the signal.

Automatic or manual transfer to a predetermined flashing mode. Manual traffic direction by proper authority. Temporary erection of other traffic control devices.

Traffic control signals have complex electrical and electronic equipment. Special training and skills are needed to provide the maintenance necessary to keep the signals operating properly and to restore the signals to operation after an equipment failure occurs. Types of work include the following: • • •

It is best to use detectors capable of registering the presence of a vehicle at the detector as well as the passage of the vehicle over the detector. Sensors (or the associated controller) may have one or more of the following characteristics, all of which add to the usefulness of the detector.

Routine preventative maintenance and identification of problems with controllers and associated equipment. Cleaning and replacement of signal lamps on a schedule that will minimize interruption of signal operation due to lamp failure. Maintenance of an adequate stock of replacement control equipment and spare parts.

• • •

The appearance and effectiveness of an installation should be maintained by scheduled cleaning and adjustment of signal lenses and reflectors and by painting signals and supports. Yellow posts should be used for post-mounted signal heads. The signal head housings, insides of visors, entire surface of louvers, and surface of backplates should have a dull black or dark green finish. Backplates may have a white border.

• •

To provide efficient and safe operation of an intersection, the traffic signal control equipment must be operated in accordance with its predetermined timing schedule. Timing changes should be made only by authorized persons. A written record should be made of all timing changes, inspections and other work done on any signal, and a copy should be placed in the cabinet. A copy of the timing plan and wiring scheme should also be kept in the cabinet. Also, a copy of all records should be maintained by the local authority.


Presence mode, which means the detector gives an indication as long as a vehicle is over the detector. Pulse mode, in which the detector gives only a short (pulse) indication when a vehicle or axle passes over it. Holding or nonholding mode. In the holding mode, the detector actuation is held after the vehicle leaves the detector until the actuation is released by the detector or controller. In the nonholding mode, the detector actuation is discontinued by the detector or the controller when the vehicle leaves the detector. Delay timing, which means the detector does not transmit the vehicle actuation to the controller for a predetermined adjustable time. Extension timing, which means the detector prolongs the transmission of an actuation to the controller after the passage of a vehicle.

At some locations, total entering traffic on the major street is more than twice the traffic on the minor street. In such cases, the detectors on the minor street should be placed closer to the stop line than those on the major street. On low-volume minor streets, vehicles entering the street from driveways between a detector and the stop line do not register their presence and may not receive the green light for a considerable time. In such cases, an additional detector should be placed between the stop line and the nearest driveway. Any vehicle crossing this detector will

9-64


9.5.12 OPERATION OF TRAFFIC CONTROL SIGNALS BY HAND CONTROL

register their presence and call for the right-ofway and will not be unnecessarily delayed. This will require a reduction in the length of the vehicle extension timing on that approach. As an alternative, the controller can be designed to respond only to the first impulse in each cycle from the detector farthest from the intersection.

A mechanism should be provided to permit authorized personnel to operate the signal manually to control traffic. This should include the required switch to transfer from automatic to hand operation, and a push button switch on a one-meter electrical cord for the purpose of changing the signal indications.

At traffic-actuated signals, detectors are required in separate turning lanes to secure the right-ofway for vehicles in those lanes. Turning vehicles can frequently complete the turn and leave the intersection on the GREEN DISK signal indication. Thus, the right-of-way does not have to be transferred to the turning lanes causing unnecessary delay to other traffic. Therefore, detectors and associated equipment for such lanes should be designed to register the need for right-of-way only when a vehicle is present in the lane.

When a traffic signal is being operated by hand control, the lengths of the yellow change intervals and red clearance intervals, if used, should be controlled by the signal timing mechanism. Properly timed and maintained traffic control signals are efficient in moving traffic through an intersection. Hand control of a signal in a progressive signal system will interrupt the smooth flow of traffic through the system. The temporary improvement in traffic flow at that intersection will be offset by a decrease in efficiency for the system as a whole. It is recommended that signals be manually controlled only for special, temporary events.

Detectors should be placed where vehicles traveling away from the intersection will not affect the controller. On narrow two-way roadways this may require a special type of directional detector which will be actuated only by vehicles going toward the intersection.

9.5.11 USE OF SIGNS WITH TRAFFIC CONTROL SIGNALS

9.6

STOP signs should be used with traffic control signals except: • • •

•

PEDESTRIAN SIGNAL INDICATIONS

9.6.1 MEANING OF PEDESTRIAN SIGNAL INDICATIONS

When the signal indication flashes red at all times. When a minor street or driveway with little traffic enters the intersection or controlled area. When the signal must be operated for a considerable time in the flashing mode. In that case, STOP signs may be desirable to supplement the flashing red signal indications. When the signal installation is temporarily without electrical power, and STOP signs must be erected on some or all of the approaches.

Pedestrian signal indications are used to give pedestrians better information for safe crossing than can be given by the vehicular indications alone. These indications consist of the green figure of a walking man, symbolizing permission to walk (WALK) and a representation of a red-colored hand, symbolizing prohibition of walking (DON'T WALK) (see Figure 9-36). Another permissible combinations would be a white figure of a walking man and a red figure of standing man, respectively. The meanings of pedestrian signal indications are:

9-65



• •

At officially designed school crossings at intersection signalized under any criterion. At wide intersections where pedestrians must make the crossing in stages.

Pedestrian signal indications are desirable wherever it is necessary to assist pedestrians, particularly at complex or large intersections. These signals show the periods of the signal cycle when pedestrian crossing has the least vehicular interference. Normally, pedestrian indications need not be placed at intersections where few pedestrians cross the major street.

9.6.3 DESIGN OF PEDESTRIAN SIGNAL INDICATIONS Figure 9-36 Pedestrian Signal

• •

•

Pedestrian indications should be adequately bright and legible to be effective under all normal atmospheric conditions. These indications should attract attention and be readable by pedestrians (day and night) at all distances from three meters to the full width of the area to be crosses.

The hand symbol (when steadily illuminated) means pedestrians facing the signal should not enter the roadway. The walking man symbol (when flashing) means pedestrians should not start to cross the roadway. However, any pedestrian who has partly completed crossing the roadway should proceed to a sidewalk or to a safety island. The walking man pedestrian indication means pedestrians may cross the roadway within the crosswalk limits in the direction of the indication.

Lenses for pedestrian indications should be round in shape, displaying either the red hand symbol or the green walking man symbol. The signal indications should be internally illuminated. When illuminated, the walking man symbol should be green on a black background. When illuminated, the hand symbol should be red on a black background.

9.6.2 USE OF PEDESTRIAN SIGNAL INDICATIONS

When not illuminated, pedestrian indications should not be readily distinguishable by pedestrians from the far end of the crosswalk.

Pedestrian signal indications should be installed in conjunction with vehicular traffic control signals under any of the following conditions: • •

•

Symbols at least 150 millimeters high should be used if the distance from the near curb to the pedestrian signal indication is 35 meters or less. Where that distance is more than 35 m, the symbols should be at least 225 millimeters in height.

When a traffic control signal is installed because either the Pedestrian Volume or the School Crossing Criterion is met. When it is necessary to give vehicles a signal indication to stop them from crossing the path of a pedestrian movement. A signal indication is then necessary to tell pedestrians when they may walk. When vehicular signal indications are not sufficiently visible to pedestrians, particularly on one-way streets or at a “T” intersection.


When pedestrians are required to cross the street on two or more stages, optically programmed Walk-Don't Walk pedestrian signal indications or symbols should be utilized. These indications should be installed so that the pedestrian will view only the indication which applies to him.

9-66


9.6.4 LOCATION OF PEDESTRIAN SIGNAL INDICATIONS

and use. Additional pushbutton detectors may be needed on median islands where a pedestrian might seek refuge from traffic.

Pedestrian signals should be mounted with the bottom of the housing not less than two meters nor more than three meters above the sidewalk level.

9.6.6 PEDESTRIAN SIGNAL PHASES AND INTERVAL TIMING Pedestrians should be assured of sufficient time to cross the roadway during the pedestrian change/clearance period at a signalized intersection where pedestrian indications are used. Some pedestrians, particularly the very young, old, or handicapped, walk more slowly than other pedestrians. The length of the pedestrian change/clearance interval must be adjusted to accommodate those differences in walking speed where young, old, handicapped pedestrians frequently cross.

For each direction on each crosswalk, pedestrian indications should be in the normal line of vision of pedestrians. The preferred location of the pedestrian signal face is at the end of each crosswalk. The indications should be positioned and adjusted for maximum visibility at the far end of the crosswalk. The pedestrian indication should be located within three meters of the extension of the crosswalk lines. Pedestrian signal heads may be mounted separately or on the same support as the vehicular signal heads. Vehicular and pedestrian signal heads on the same support should be separated by a space of not less than 150 millimeters when both signal heads face in the same direction.

Pedestrian pushbutton control of traffic-actuated signals gives pedestrians sufficient crossing time by extending the green time given to vehicles. Even where traffic signals are pretimed it is sometimes desirable to provide pedestrian pushbuttons. Often pedestrian detectors are installed for crosswalks across the major street, but not across the minor street. In those cases, pedestrian actuation extends the minor street vehicular green time which will usually reduce the major street green time. Where pedestrian actuation is not practical, and pedestrians or often present, the vehicular green time should provide at least the minimum crossing time needed by pedestrians.

Pedestrian signal heads and indications should meet the specifications of the Emirate of Abu Dhabi with respect to color, lens transmittance, light distribution, and physical characteristics.

9.6.5 PEDESTRIAN PUSHBUTTON DETECTORS

The minimum Walk interval, when the green walking man indication is shown, should be not less than the minimum time required to cross the street at walking speed. The minimum Walk interval is typically three to seven seconds. Additional time, if needed, should be added to the clearance period. The Walk indication may be shown for the vehicular green period minus the time required for the pedestrian change/clearance indication. However, the length of the Walk period need not equal the time required for pedestrians to walk completely across the street, as they can complete their crossing during the change/clearance period. At traffic-actuated signals, the standing man indication should be shown unless there has been a pedestrian actuation.

Pedestrian detectors should be installed at any traffic-actuated signal for any crosswalk having pedestrian indications except as described in Section 9.6.6. Detectors and indications should be omitted for a crosswalk if it is closed. Pedestrian detectors (usually buttons which must be pushed by pedestrians) should be located within easy reach of pedestrians at each end of each crosswalk where pedestrian actuation is required. The position of the pushbutton with respect to the crosswalk should clearly show it is intended for pedestrians using that crosswalk. Detectors should be mounted on a strong support at a height of from 1 to 1.2 meters above the sidewalk. Small signs should be mounted above or as a part of each detector to explain their purpose

9-67



A pedestrian change/clearance interval should always be provided where pedestrian signal indications are used. This interval should be long enough to allow a pedestrian to walk across the entire roadway or to a median island before vehicles crossing his path receive a green indication. The normal walking speed is assumed to be 1.25 meters per second.

The hazard or other condition warranting a hazard identification beacon will usually determine its location and the sign used with it.

Pedestrian indications should always be displayed when the traffic signal is operating as a stop-and-go device. Pedestrian indications should not be illuminated when the traffic control signal is operating as a flashing device. When pedestrian pushbuttons are provided, the buttons should be operating at any time the pedestrian indications are operating.

A 300-millimeter lens should be used only with a sign larger than the standard size.

9.7

A hazard identification beacon should be supplemented by a suitable sign when used on an obstruction in the roadway. In addition, the area of the obstruction should be illuminated.

9.7.2 SPEED LIMIT SIGN BEACON Speed limit sign beacons are intended for use where signs alone have not been effective in controlling speed. The beacons are required with mechanically or electrically changeable speed limit signs. Too frequent use of the beacons, however, may reduce their effectiveness.

FLASHING BEACONS

9.7.1 HAZARD IDENTIFICATION BEACONS

A speed limit sign beacon is a signal having one or two AMBER DISK lens sections. If one lens is used, it should have a visible diameter of not less than 200 millimeters. If two lenses are used, the lenses should have visible diameter of not less than 150 millimeters. The two lenses should be illuminated alternately. If the sign is higher than it is wide, one lens should be at the top of the sign and the other at the bottom. If the sign is longer horizontally than it is high, the lenses may be at the left and right of the sign. A 300-millimeter lens may be used only with a speed limit sign larger than the standard size.

A hazard identification beacon is a traffic signal giving a flashing AMBER DISK indication. A hazard identification beacon may have one or two yellow indications. If there are two, the indications should be flashed alternately. The beacon should be used only to supplement an appropriate warning or regulatory sign. Typical uses for hazard identification beacons include the following: • • • • •

Warn of obstructions in or immediately adjacent to the roadway. Call attention to and increase the effectiveness of warning signs. Provide warning for crosswalks, especially those not at an intersection. Warn of intersections, particularly where accidents have been recorded. Supplement and call attention to regulatory signs, except for stop, give-way and entryprohibited signs. If a beacon is needed for those three signs, it should be red.

A speed limit sign beacon may be used with a standard speed limit sign which shows an unchanging message. It may also be used with speed limit sign on which the indicated speed limit may be changed mechanically, electrically, or by hand. A changeable message speed limit sign beacon may be controlled by a seven-day programmable time clock or other reliable means so the beacon operates only during those hours and days when the regulation is in effect.

Hazard identification beacons should be operated only during those hours when the hazard or regulation exists.


9-68


9.7.3 INTERSECTION CONTROL BEACON

One should be on the right side of the approach and one overhead or on the left of the approach. This will usually be more effective than a beacon with a 300-millimeter lens. If two lenses are used with a STOP sign, the lenses should be placed above and below the sign, and should be alternately illuminated. The standard beacon should have one lens. Two-lens beacons should only be used where accident experience shows singlelens beacons have not been effective.

Intersection control beacons have flashing AMBER DISK or RED DISK indications in each face. These beacons are used at intersections to warn and control one or more directions of travel. More than one indication may be needed on some approaches to provide adequate visibility. Intersection control beacons are used at intersections where traffic control signals are not warranted, but accident experience indicates a special hazard. Only the following combinations of signal indications should be used: • •

9.7.5 DESIGN AND OPERATION OF FLASHING BEACONS Flashing beacons usually consist of one or more sections of a traffic control signal head. Except as modified by this section, the physical and optical characteristics of beacons should comply with the requirements for traffic control signal heads.

Amber indications on one route (normally the major route) and red on all other approaches, or Red on all approaches to the intersection. This is permissible only where an all-way stop is warranted.

The lens in each beacon, except the speed limit sign beacon, should have a visible diameter of not less than 200 millimeters.

A STOP sign in the normal, approved location should be used with flashing red intersection control beacon. Intersection advance Warning signs are normally used on approaches having a flashing yellow beacon. Flashing yellow beacons should never face two or more vehicle movements which cross or otherwise conflict.

When illuminated, the indication of the beacon should be clearly visible as a full disk in the direction it is aimed. Unless it is physically obstructed, the indication should be visible for a distance of at least 400 meters under all normal lighting and atmospheric conditions.

Two-hundred millimeter lenses are customarily used in intersection control beacons. Three-hundred millimeter lenses may be used where high traffic volume or speed necessitate greater visibility and effectiveness.

All beacons should be flashed at a rate of not less than 50 nor more than 80 times per minute. The illuminated period of each flash should not be less than one-half more than two-thirds of the total cycle. The mechanism that causes the beacons to flash should be equipped with filtering devices for suppression of radio frequency electrical interference.

If two or more indications are shown to any one approach, these indications should be flashed simultaneously.

When a 1,750-lumen lamp is used in a 300-millimeter yellow flashing beacon, the indication may be excessively bright at night. Therefore, except in urban areas with bright surroundings and on high speed rural roads, a device should be used to automatically reduce the light output of the beacon at night proportionally as the ambient light level decreases. The reduction should be to not more than 50 percent and not less than 30 percent of the light output at full rated voltage.

9.7.4 STOP SIGN BEACON A stop sign beacon is a signal with one or two flashing RED DISK indications used with a STOP sign. The lens of a stop sign beacon should have a visible diameter of not less than 200 millimeters. Where greater effectiveness is needed, two separate beacon and sing installations may be made.

9-69



Flashing beacons, except for intersection control beacons, are generally used with signs. If so, these beacons must be separated by 300 to 400 millimeters from the nearest edge of the sign (this limitation does not apply to school-zone speed limit beacons). If the beacon is too close to the sign, its brilliance will seriously interfere with the legibility of the sign at night. Flashing beacons should never be mounted on pedestals in the roadway. A flashing beacon may be placed on a pedestal on a traffic or pedestrian island, but the support should be of breakaway design. The installation for the sign will usually establish the location, height, and lateral clearance of the combined sign and beacon. The beacon alone or with an accompanying sign may be over the roadway. In such cases, the clearance above the pavement should not be less than 5.8 meters nor more than 6.5 meters. The sign and flashing beacon should be in the same vertical plane.


9-70

ADM Traffic Control Devices Manual 0-1_2004R

Recommend Documents