As 1576.1 Scaffolding General Requirements

AS/NZS 1576.1:1995

Australian/New Zealand Standard

Scaffolding

Accessed by Clough Engineering on 05 Sep 2001

Part 1: General Requirements

AS/NZS 1576.3:1995

This Joint Australian/New Zealand Standard was prepared by Joint Technical Committee BD/36, Scaffolding. It was approved on behalf of the Council of Standards Australia on 24 October 1994 and on behalf of the Council of Standards New Zealand on 7 November 1994. It was published on 5 January 1995.

The following interests are represented on Committee BD/36:


A.C.T. Occupational Health and Safety Office Aluminium Development Council, Australia Australian Chamber of Commerce and Industry Australian Institute of Building Surveyors Department of Employment, Vocational Education, Training and Industrial Relations, Qld Department of Labour, New Zealand Department of Occupational Health, Safety and Welfare, W.A. Master Builders Australia Metal Trades Industry Association of Australia National Association of Scaffolding and Formwork Contractors, Australia New Zealand Contractors Federation New Zealand Engineering Federation Occupational Health and Safety Authority, Vic. Tasmania Development and Resources Work Health Authority, N.T. WorkCover Authority, N.S.W.

Review of Standards. To keep abreast of progress in industry, Joint Australian/New Zealand Standards are subject to periodic review and are kept up to date by the issue of amendments or new editions as necessary. It is important therefore that Standards users ensure that they are in possession of the latest edition, and any amendments thereto. Full details of all Joint Standards and related publications will be found in the Standards Australia and Standards New Zealand Catalogue of Publications; this information is supplemented each month by the magazines ‘The Australian Standard’ and ‘Standards New Zealand’, which subscribing members receive, and which give details of new publications, new editions and amendments, and of withdrawn Standards. Suggestions for improvements to Joint Standards, addressed to the head office of either Standards Australia or Standards New Zealand, are welcomed. Notification of any inaccuracy or ambiguity found in a Joint Australian/New Zealand Standard should be made without delay in order that the matter may be investigated and appropriate action taken.

AS/NZS 1576.1:1995

Australian/New Zealand Standard

Scaffolding Part 1: General Requirements


First published as part of AS 1576—1974. Revised and redesignated in part as AS 1576.1—1991. Jointly revised and designated as Joint Standard AS/NZS 1576.1:1995.

PUBLISHED JOINTLY BY:

STANDARDS AUSTRALIA 1 The Crescent, Homebush NSW 2140 Australia STANDARDS NEW ZEALAND Level 10, Radio New Zealand House, 155,The Terrace, Wellington 6001 New Zealand ISBN 0 7262 9410 1

PREFACE This Standard was prepared by the Joint Standards Australia/Standards New Zealand Committee BD/36 on Scaffolding to supersede AS 1576.1—1991. It is issued as a joint Standard under the terms of the Active Cooperation Agreement between Standards Australia and Standards New Zealand. This Standard is part of the following series: AS 1576

Scaffolding

1576.2

Part 2: Couplers and accessories

1576.3 Supp1 Supplement 1: Prefabricated and tube–and–coupler scaffolding—Metal tube–and–coupler scaffolding—Deemed to comply 1576.4

Part 4: Suspended scaffolding

AS/NZS 1576

Scaffolding

1576.1

Part 1: General requirements

1576.3

Part 3: Prefabricated and tube–and–coupler scaffolding

1576.5*

Part 5: Prefabricated splitheads and trestles

This edition incorporates the following major changes from AS 1576.1—1991. (a) The referenced Standards have been updated. (b) Some New Zealand Standards are now referred to. (c) Clause 2.2 now refers to AS 1250. (d) Clause 2.3.1 refers to permissible state design. (c) Clause 2.7 has been fully revised. (f) Item (f) of Clause 3.6.4 uses the dimension 900 mm instead of 1000 mm.


*

In course of preparation

E Copyright — STANDARDS AUSTRALIA/STANDARDS NEW ZEALAND Users of Standards are reminded that copyright subsists in all Standards Australia and Standards New Zealand publications and software. Except where the Copyright Act allows and except where provided for below no publications or software produced by Standards Australia or Standards New Zealand may be reproduced, stored in a retrieval system in any form or transmitted by any means without prior permission in writing from Standards Australia or Standards New Zealand. Permission may be conditional on an appropriate royalty payment. Australian requests for permission and information on commercial software royalties should be directed to the head office of Standards Australia. New Zealand requests should be directed to Standards New Zealand. Up to 10 percent of the technical content pages of a Standard may be copied for use exclusively in–house by purchasers of the Standard without payment of a royalty or advice to Standards Australia or Standards New Zealand. Inclusion of copyright material in computer software programs is also permitted without royalty payment provided such programs are used exclusively in–house by the creators of the programs. Care should be taken to ensure that material used is from the current edition of the Standard and that it is updated whenever the Standard is amended or revised. The number and date of the Standard should therefore be clearly identified. The use of material in print form or in computer software programs to be used commercially, with or without payment, or in commercial contracts is subject to the payment of a royalty. This policy may be varied by Standards Australia or Standards New Zealand at any time.

CONTENTS


Page SECTION 1 SCOPE AND GENERAL 1.1 SCOPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 REFERENCED DOCUMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4 TYPES OF SCAFFOLD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4 4 5 6

SECTION 2 DESIGN REQUIREMENTS 2.1 PRINCIPLES OF DESIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 BASIS OF DESIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3 LOAD COMBINATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4 DESIGN LOADS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 SUPPORTING STRUCTURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6 BRACING MEMBERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7 STABILITY OF FREESTANDING SCAFFOLDS . . . . . . . . . . . . . . . . . . . . 2.8 ANCHORAGE AND TIE ASSEMBLIES . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.9 STEEL WIRE ROPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.10 FIBRE ROPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.11 STEEL CHAIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.12 ECCENTRIC LOADING OF COMPRESSION MEMBERS . . . . . . . . . . . 2.13 DESIGN OF LEDGERS, PUTLOGS AND TRANSOMS . . . . . . . . . . . . . . 2.14 DESIGN OF STANDARDS AND SPURS .......................

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SECTION 3 OPERATIONAL REQUIREMENTS 3.1 WORKING PLATFORM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 ACCESS PLATFORM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3 CATCH PLATFORM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4 SLOPE OF PLATFORMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5 EDGE PROTECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.6 ACCESS TO AND EGRESS FROM WORKING PLATFORMS . . . . . . . . 3.7 ADDITIONAL REQUIREMENTS FOR MOBILE SCAFFOLDS . . . . . . . 3.8 ADDITIONAL REQUIREMENTS FOR PLATFORM BRACKETS . . . . . . 3.9 TUBE EXTENSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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STANDARDS AUSTRALIA/STANDARDS NEW ZEALAND Australian/New Zealand Standard Scaffolding Part 1: General requirements S E C T I O N

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S C O P E

A N D

G E N E R A L

1.1 SCOPE This Standard sets out design and operational requirements for scaffolding, except trestle scaffolding, portable ladders intended to be used as working platforms and elevating working platforms.


1.2 REFERENCED DOCUMENTS The following documents are referred to in this Standard: AS 1170 1170.1 1170.2 1170.3

Minimum design loads on structures Dead and live loads and load combinations Wind loads Snow loads

1250

The use of steel in structures

1538

Cold-formed Steel Structures Code

1554 1554.1

Structural steel welding Part 1: Welding of steel structures

1576 1576.2* 1576.4*

Scaffolding Part 2: Couplers and accessories Part 4: Suspended scaffolding

1577

Scaffold planks

1657*

Fixed platforms, walkways, stairways, and ladders — Design, construction and installation

1664

Rules for the use of aluminium in structures

1665

Welding of aluminium structures

1720 1720.1

Timber structures Part 1: Design methods

1892 1892.1 1892.2

Portable ladders Part 1: Metal Part 2: Timber

2121

The design of earthquake-resistant buildings

2321

Short-link chain for lifting purposes (non-calibrated)

3569

Steel wire ropes

* New Zealand has declared this to be a harmonized Standard with an NZS/AS designation.

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AS 4100

Steel structures

4142 4142.2

Fibre ropes Part 2: Three-strand hawser-laid and eight-strand plaited

AS / NZS 1576.1:1995

AS/NZS 1576 Scaffolding 1576.3 Part 3: Prefabricated and tube-and-coupler scaffolding NZS 3404 3404.1

Steel structures Standard Part 1: Steel structures Standard

3603

Timber structures Standard

3609

Specification for timber ladders

3620

Scaffold planks

4203

General structural design and design loadings for buildings

4701

Metal-arc welding of steel structures

5233

Specification for portable ladders (other than timber ladders)

NZS/BS 302 Stranded steel wire ropes 302.2 Part 2: Specification for ropes for general purposes 2052

Specification for ropes made of manila, sisal, hemp, cotton and coir

NZS/ISO 1835 Short link chain for lifting purposes— Grade M(4), non-calibrated, for chain slings etc. 1836

Short link chain for lifting purposes— Grade M(4), calibrated, for chain hoists and other lifting appliances

3075

Short link chain for lifting purposes— Grade S(6) non-calibrated, for chain slings etc.

3076

Short link chain for lifting purposes—Grade T(8), non-calibrated, for chain slings etc.

3077

Short link chain for lifting purposes— Grade T(8), calibrated, for chain hoists and other lifting appliances


1.3

DEFINITIONS For the purpose of this Standard, the definitions below apply.

1.3.1 Access platform —a platform that is only used or intended to be used to provide access for persons, or for persons and materials to or from places of work. 1.3.2 Baseplate —a plate to distribute the load from a load-bearing member to the supporting structure. 1.3.3 Bay — the space enclosed by four adjacent standards, or the equivalent space in a single pole scaffold. 1.3.4 Brace — a member fixed diagonally to two or more members of the scaffold to provide rigidity to the scaffold. 1.3.5 Castor —a swivelling wheel attached to the lower end of a standard for the purpose of supporting and moving a scaffold. 1.3.6

Catch platform —a platform attached to a scaffold to contain falling debris. NOTE: A cantilevered catch platform is also called a fan. COPYRIGHT

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1.3.7

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Cradle — that portion of the assembly incorporating a suspended platform.

1.3.8 Guardrailing — a structural member to prevent persons from falling off any platform, walkway, stairway or landing. 1.3.9 Landing — a level area used to provide access to a stairway or ladder, or located at an intermediate level in a system of stairways or ladders. 1.3.10

Ledger —a horizontal structural member longitudinally spanning a scaffold.

1.3.11 Lift — the vertical distance from the supporting surface to the lowest ledger or level at which a platform can be constructed, or the vertical distance between adjacent ledgers or levels at which platforms can be constructed. 1.3.12 Loading bay — a platform on a scaffold for the storage of materials and equipment. 1.3.13

Platform —an elevated surface.

1.3.14 Platform bracket— a bracket attached to the scaffold to enable a platform to be placed between the scaffold and the building or structure. 1.3.15 Putlog — a horizontal structural member spanning between ledgers or a ledger and an adjacent wall, and intended to support a platform. 1.3.16 Scaffold — a temporary structure, specifically erected to support access platforms or working platforms. 1.3.17 Scaffold plank— a decking component, other than a prefabricated platform, that is used or intended to be used in construction of any platform supported by a scaffold. 1.3.18 Soleplate —a member used to distribute the load through a baseplate to the ground or other supporting structure. 1.3.19 Spur— an inclined load-bearing member that transmits a load to the supporting structure. 1.3.20 Standard —a vertical structural member that transmits a load to the supporting structure. 1.3.21

Strut — a scaffold member subject to a compressive force.

1.3.22 Supporting structure—any structure, structural member or foundation that supports a scaffold. 1.3.23 Tie —a member or assembly of members used to tie a scaffold to a supporting structure.


1.3.24 Transom — a horizontal structural member transversely spanning an independent scaffold at the standards. 1.3.25 Working load limit — the maximum working load that may be applied to any component or system. 1.3.26 Working platform — a platform on a scaffold, to support persons and materials or equipment for use by them. 1.4

TYPES OF SCAFFOLD Common types of scaffolds include the following:

(a)

A single pole scaffold consists of a single row of standards connected by ledgers. Putlogs are fixed to the ledgers and built into the wall of the building or structure.

(b)

An independent scaffold consists of two or more rows of standards connected longitudinally and transversely. (i)

A tower scaffold is an independent scaffold consisting of four vertical members connected longitudinally and transversely.

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(ii)

A mobile scaffold is an independent scaffold that is freestanding and mounted on castors.

(iii)

A hung scaffold is an independent scaffold that hangs from another structure, but is not capable of being raised or lowered when in use.

(iv)

A birdcage scaffold is an independent scaffold that consists of more than two rows of standards in both directions, connected by ledgers and transoms.

A suspended scaffold incorporates a suspended platform that is capable of being raised or lowered when in use.

(d)

A boatswain’s chair is a suspended scaffold of which the platform is a chair, or similar appliance, suitable for use by one person.

(e)

A spur scaffold is partially supported by spurs.

(f)

A cantilever scaffold is supported by cantilevered load-bearing members.


(c)

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2

D E S I GN

R E Q U I R E M E N T S

2.1 PRINCIPLES OF DESIGN The design of the scaffold shall take into account the following: (a)

The strength, stability and rigidity of the supporting structure.

(b)

The handling normally associated with scaffolding.

(c)

The safety of persons engaged in the erection, alteration and dismantling of the scaffold.

(d)

The safety of persons using the scaffold.

(e)

The safety of persons in the vicinity of the scaffold.

2.2 BASIS OF DESIGN The design of the structural members and components of a scaffold shall comply with AS 1250, AS 1538, AS 1664, AS 1720.1, AS 4100, NZS 3404.1 or NZS 3603, as appropriate, and as modified by the requirements of this Standard. Welding shall comply with AS 1554.1, AS 1665 or NZS 4701, as appropriate. 2.3

LOAD COMBINATIONS

2.3.1 General Where scaffolding is designed, it shall be designed for the most adverse combination of dead loads, live loads and environmental loads that can reasonably be expected during the period that the scaffold is expected to be in service. Load combinations for strength limit states shall be in accordance with AS 1170.1 or NZS 4203, as appropriate, except that dead and live load combinations shall be as follows: 2.0G + 2.0Q where G = dead load Q = live load (including impact, if any). Where environmental loads will be such that work is unlikely to proceed under those conditions, then the worst case may be restricted to dead loads, expected live loads from stacked materials and environmental loads. For permissible stress design, the sum of the dead and live loads applied shall be increased by 15 percent, to allow for re-use of materials.


2.3.2 Tube mix For a tube and coupler scaffold built from plain steel tube of 48.3 mm outside diameter, the load combinations to be considered shall include the following: (a)

The self weight of the scaffold structure, calculated on the assumption that all members have a wall thickness of 4.88 mm.

(b)

The strength of all members calculated on the basis of members having a wall thickness of 4.00 mm. NOTE: Items (a) and (b) above are necessary to allow for the large quantities of tubes in service that have either wall thickness, and the difficulty in detecting tubes of different wall thickness in a completed scaffold.

(c)

Where galvanized tube with a wall thickness of 3.2 mm is used in a scaffold in New Zealand, the strength of every member of the scaffold shall be calculated on the basis that every member has a wall thickness of 3.2 mm. Where a scaffold does not include tube with a wall thickness of 3.2 mm, the strength of the members may be determined in accordance with Item (b) above. COPYRIGHT

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2.4

AS / NZS 1576.1:1995

DESIGN LOADS

2.4.1 Dead load The dead load (G) shall include the self weight of the scaffold structure and components including working platforms, catch platforms, access platforms, stairways, ladders, screens, sheeting, platform brackets, suspension ropes, secondary ropes, traversing ropes, tie assemblies, scaffolding hoists, electrical cables and any other attachment, where appropriate. 2.4.2 Environmental loads the following:

Where appropriate, the environmental loads shall include

(a)

Wind loads in accordance with AS 1170.2 or NZS 4203, as appropriate, imposed on the scaffold, including any guardrails, toeboards, stacked materials, screens, sheeting, platform ropes, guy wires and other attachments.

(b)

Snow loads in accordance with AS 1170.3 or NZS 4203, as appropriate.

(c)

Rain and ice loads, where it is considered likely that the scaffold and claddings will be subject to rain or a build-up of ice.

(d)

Earthquake loads in accordance with AS 2121 or NZS 4203, as appropriate.

2.4.3

Live loads

2.4.3.1

General

The live load (Q) shall include the following:

(a)

The weight of persons.

(b)

The weight of materials and debris.

(c)

The weight of tools and equipment.

(d)

Impact forces.

2.4.3.2 Duty live loads The live load applied to a working platform shall be categorized by the following duty conditions: (a)

Light duty, a load of 2.2 kN per bay that includes a single concentrated load of 1 kN.

(b)

Medium duty, a load of 4.4 kN per bay that includes a single concentrated load of 1.5 kN.

(c)

Heavy duty, a load of 6.6 kN per bay that includes a single concentrated load of 2 kN.

(d)

Special duty, the largest intended load but not less than heavy duty.

The single concentrated load shall be placed in the most adverse position within the bay.


2.4.3.3

Weight of person

The weight of a person shall be taken as not less than 80 kg.

2.4.3.4 Guardrailing or handrailing The live load acting on guardrailing or handrailing shall be as specified in AS 1657 for guardrailing. 2.4.3.5 Perimeter mesh guards or screens Perimeter mesh guards or screens that are intended to perform the function of a guardrail shall be designed for the live load of guardrailing in accordance with Clause 2.4.3.4. 2.4.3.6 Catch platforms The live load acting on a catch platform shall be the largest expected load but not less than a uniformly distributed load of 5 kPa applied normal to the catch platform. 2.4.3.7 Loading bays The live load acting on a loading bay for material or equipment storage shall be the largest intended load but not less than a uniformly distributed load of 5 kPa. The largest intended live load for a loading bay shall be increased by a factor of not less than 1.25 to allow for the effect of impact. COPYRIGHT

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2.4.3.8 Stair access systems Components for stair access systems, including landings, shall be designed to the load requirements of AS 1657. The live load acting on that part of the scaffold supporting the stair access system shall be taken as not less than 2.5 kPa over each stairtread and each landing. 2.4.3.9 Boatswain’s chair The basic live load (i.e. not including impact) applied to a boatswain’s chair and supporting rig shall be not less than 1 kN. This live load shall then be increased by a factor of not less than 1.25 to allow for the effect of impact. 2.4.3.10 Cradles The basic live load (i.e. not including impact) applied to a cradle shall be the largest intended live load but shall be not less than light duty. This live load shall then be increased by a factor of not less than 1.25 to allow for the effect of impact. NOTE: The supporting rig is required to comply with Clause 2.3.

2.4.3.11 Working platforms for independent scaffolds The live load applied to a working platform supported by independent scaffolding shall be one of the following loadings: (a)

Light duty.

(b)

Medium duty.

(c)

Heavy duty.

(d)

Special duty loading.

2.4.3.12 Working platforms for single pole scaffolds The live load applied to a working platform supported by single pole scaffolding shall be either of the following loadings: (a)

Heavy duty.

(b)

Special duty.

2.4.3.13 Access platforms the following loadings: (a)

Heavy duty.

(b)

Special duty.

The live load applied to an access platform shall be either of

2.4.3.14 Ladder landings The live load applied to a ladder landing shall be the live load applicable to the scaffold that the ladder services. 2.4.3.15 Platform brackets The live load applied to a platform bracket shall be the largest intended load but not less than 2 kN acting downwards at the outermost edge of the bracket.


2.5

SUPPORTING STRUCTURE

2.5.1 General The supporting structure shall be capable of supporting the most adverse combination of loads applied by the scaffold during the period of its service. 2.5.2 Strengthening of supporting structure Where the supporting structure is not capable of supporting the most adverse combinations of expected loads in Clause 2.5.1, it shall be strengthened by propping or other means. 2.5.3 Soleplates Where soleplates are required, they shall be designed to distribute the load from a scaffold to the supporting structure. 2.6 BRACING MEMBERS Bracing members shall be designed to resist not less than 2.5 percent of the vertical load in any member to which they are connected, together with any horizontal loads such as wind loads.

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2.7 STABILITY OF FREESTANDING SCAFFOLDS The dead load alone shall be sufficient to prevent each freestanding scaffold that is set up in a ready-to-use condition (i.e. a working condition) from overturning, while the scaffold is subjected to 1.5 times the following loadings, each applied separately: (a)

A loading in the most adverse direction, consisting of an outwards horizontal component of 300 N applied at the centre of each bay to the uppermost horizontal member, together with a vertical component of 750 N applied at the middle of each bay 200 mm in from the outermost edge of the working platform (see Figure 1).

(b)

The loading, calculated in accordance with AS 1170.2 or NZS 4203, as appropriate, that would be applied by anticipated wind during the period that the scaffold is to be erected, without any live loading on the scaffold.


NOTE: The dead load of a scaffold may be increased by securely attaching counterweights to the scaffold near its base.

NO TE: This sketch does not show any planks, midrail, toeboard or infill.

FIGURE 1

2.8

STABILITY LOADING OF FREESTANDING SCAFFOLDS

ANCHORAGE AND TIE ASSEMBLIES

2.8.1 General Where anchorage or tie systems are used to stabilize the scaffold, their design shall be such that neither the scaffold nor any building or supporting structure is overloaded or damaged during normal use.

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2.8.2 Location of ties The location of anchorage and tie systems shall not obstruct clear access along the full length of any working platform or access platform. 2.8.3 Strength of ties Tie assemblies shall be spaced vertically and horizontally to stabilize the scaffold against the combined effect of— (a)

environmental loads; and

(b)

horizontal tensile and compressive forces of not less than 2.5 percent of the vertical loads acting at the level of each tie assembly.

Each tie assembly shall have a minimum tensile and compressive working load capacity of 6.0 kN. Where an anchorage or tie assembly is required to sustain loads other than those specified in Item (b) above (e.g. scaffold on an inclined foundation), the anchorage or tie shall be designed for such additional load. 2.8.4 Drilled-in anchorages Drilled-in anchors, whether expanding or chemical types that are subjected to tensile loads, shall only be used where it is not practical to secure the scaffold in any other way. Drilled-in anchors shall comply with the following requirements: (a)

A safety factor of 3.0 on the average failure load of the anchor shall be applied to determine the working load limit.

(b)

An assessment shall be made of the material to which the drilled-in anchors are applied.

2.9 STEEL WIRE ROPE Steel wire rope shall comply with AS 3569 in Australia or NZS/BS 302.2 in New Zealand and, except where used for lifting purposes, shall not be subjected to a load that exceeds one-sixth of the manufacturer’s guaranteed minimum breaking load of such rope. 2.10 FIBRE ROPE Fibre rope shall comply with in Australia AS 4142.2 or in New Zealand NZS/BS 2052 and shall not be subjected to a load greater than one-tenth of the manufacturer’s guaranteed minimum breaking load of such rope. 2.11 STEEL CHAIN Steel chain shall comply with AS 2321, NZS/ISO 1835, NZS/ISO 1836, NZS/ISO 3075, NZS/ISO 3076 or NZS/ISO 3077, as appropriate, and shall not be subjected to a load greater than one-sixth of the manufacturer’s guaranteed minimum breaking load of such chain.


2.12

ECCENTRIC LOADING OF COMPRESSION MEMBERS

2.12.1 General Compression members include standards and spurs; however, braces may be compression or tension members. 2.12.2 Standards The compression loads on standards shall be taken as acting at a distance equal to the maximum radius of gyration measured from the centre-line of the member. NOTE: The design should take into account any moment at a critical node point on a standard.

2.12.3 Spurs and braces The compression loads shall be taken as acting at the actual distance, but not less than 40 mm from the centre-line of the member. 2.13 DESIGN OF LEDGERS, PUTLOGS AND TRANSOMS Any ledger, putlog or transom that is intended to support a platform in any bay shall be designed for not less than two-thirds of the duty live load for the bay.

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Where a ledger or transom is intended to support platforms in adjacent bays, it shall be designed for not less than two-thirds of the duty live load in each bay. 2.14

DESIGN OF STANDARDS AND SPURS

2.14.1 Platform loads on standards or spurs Any standard, spur or similar member that is intended to support a platform in any bay shall be designed for not less than one-third of the duty live load for the bay. Where a standard, spur or similar member is intended to support platforms in adjacent bays, it shall be designed for not less than one-third of the platform design load in each bay. 2.14.2 Effective length of standards at base of scaffold In the design of standards at the base of a scaffold, the effective length shall be not less than 0.85 times the actual length.


2.14.3 Effective length of struts In the design of any vertical load-bearing member in compression, the effective length of struts other than those given in Clause 2.14.2 shall be not less than 1.0L where L is the length of strut between intersecting members providing lateral support.

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S E C T I O N 3 O P E R AT I O N A L R E Q U I R E M E NT S 3.1 3.1.1

WORKING PLATFORM General

A working platform other than a boatswain’s chair shall—

(a)

have a slip-resistant surface;

(b)

be closely decked;

(c)

not be capable of uplift under working conditions; and

(d)

be level and free of trip-hazards.

Scaffold planks shall comply with AS 1577 in Australia or NZS 3620 in New Zealand. Prefabricated platform units shall comply with AS/NZS 1576.3. 3.1.2

Dimensions

3.1.2.1 Light duty less than 450 mm.

The length or width of a light-duty working platform shall be not

3.1.2.2 Medium duty The length or width of a medium-duty working platform shall be not less than 900 mm. 3.1.2.3 Heavy duty less than 1000 mm.

The length or width of a heavy-duty working platform shall be not

3.1.2.4 Special duty The dimensions of a special-duty working platform shall be not less than those of Clause 3.1.2.3. 3.1.2.5 Boatswain’s chair The seat of a boatswain’s chair shall be of sufficient dimensions to comfortably accommodate the occupant. 3.1.2.6 Suspended platform less than 450 mm. 3.2

The length or width of a suspended platform shall be not

ACCESS PLATFORM An access platform shall comply with Clause 3.1.1.

The clear width of an access platform measured between guardrailings shall be— (a)

not less than 675 mm for persons and materials; and

(b)

not less than 450 mm for persons and hand tools only.


3.3 CATCH PLATFORM requirements:

A catch platform

shall comply with the following

(a)

The platform inclination may be at any angle.

(b)

The platform shall be closely decked.

(c)

The minimum width and length shall be sufficient for the intended task.

(d)

The platform shall not be capable of uplift under working conditions.

3.4

SLOPE OF PLATFORMS

3.4.1 Working platforms from the horizontal.

The slope of a working platform shall not exceed 7 degrees

3.4.2 Access platform The slope of an access platform shall not exceed 20 degrees from the horizontal. When the slope exceeds 7 degrees, the platform shall be cleated.

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3.5 3.5.1

AS / NZS 1576.1:1995

EDGE PROTECTION General

Edge protection for suspended scaffolds shall comply with AS 1576.4.

Except as provided by Clause 3.5.5, wherever a person or object could fall a distance of 2 m or more from any platform, edge protection in the form of guardrailings and toeboards, or mesh screens incorporating kickplates shall be provided. 3.5.2

Toeboards

Toeboards shall comply with the following requirements:

(a)

They shall be scaffold planks complying with AS 1577 in Australia or NZS 3620 in New Zealand or be of material and construction that has sufficient strength and rigidity for their intended task.

(b)

They shall extend not less than 150 mm above the top surface of the platform.

(c)

No gap between the toeboard and platform shall exceed 10 mm.

(d)

They shall be securely fixed to the floor or posts.

3.5.3

Guardrailings

Guardrailings shall comply with the following requirements:

(a)

Wire ropes or fibre ropes shall not be used.

(b)

Except to close off access openings in guardrailing, chain shall not be used.

(c)

Timber guardrails shall be of sound Australian hardwood, oregon or other timber of similar strength and characteristics and of sizes not less than given in AS 1657.

(d)

Guardrails shall be securely fixed parallel to the platform at a height above the platform of not less than 900 mm nor more than 1100 mm.

(e)

Guardrails shall be no more than 100 mm outside the edge of the platform.

(f)

Unless infill complying with AS 1657 is provided between the guardrail and the toeboard, a midrail shall be provided.


3.5.4 Mesh screens Where mesh screens are provided instead of guardrailings and toeboards, they shall comply with the following requirements: (a)

They shall be securely fixed parallel to the platform and shall extend not less than 900 mm above the platform.

(b)

They shall be vertical.

(c)

They shall incorporate a kickplate that extends not less than 150 mm above the top surface of the platform.

(d)

No gap between the kickplate and the platform shall exceed 10 mm.

(e)

The top or exposed edges of mesh screens shall be suitably protected where there exists the potential risk of injury to persons.

3.5.5 Omission of edge protection Edge protection may be omitted at points of access from a stairway or ladder or at edges of platforms adjacent to the face of a building or structure, provided that the following are complied with: (a)

Points of access to stairways or ladders are adequately protected with gates, safety chains or other means or are sufficiently distant from working platforms to prevent persons working from such platforms inadvertently falling through any opening.

(b)

Where a toeboard or kickplate is omitted adjacent to the face of a building or structure (other than a working face), such face shall be— (i)

no more than 10 mm from the platform edge;

(ii)

shall extend at least 150 mm above the top of the platform; and

(iii)

shall be of strength and rigidity not less than that of a toeboard.

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(c)

Where a toeboard or kickplate is omitted adjacent to the working face of a building or structure, the gap between the platform edge and such face shall be less than 225 mm and adequate safeguards shall be taken to prevent any person being endangered in the event of debris falling.

(d)

Where a guardrail is omitted adjacent to the face of a building or structure (other than a working face), such face shall not be greater than 100 mm from the platform edge, shall have strength and rigidity not less than that of a guardrail, shall extend at least 900 mm above the top surface of the platform and shall, in all other respects, adequately perform the function of a guardrail.

(e)

Where a guardrail is omitted adjacent to a working face of a building or structure, such face shall be less than 225 mm from the platform edge, shall have strength and rigidity not less than that of a guardrail, shall extend at least 900 mm above the top surface of the platform and shall in all other respects adequately perform the function of a guardrail.

3.5.6 Additional protection Where equipment or materials are intended to be deposited on a platform to a height exceeding the height of the toeboard or kickplate and in a position where there is any likelihood of such materials or equipment falling or being knocked from the platform, additional infill specifically designed for this purpose shall be fitted. 3.6

ACCESS TO AND EGRESS FROM WORKING PLATFORMS

3.6.1 General Safe access to and egress from all working platforms shall be provided. Such access shall take the form of stairways, access ways, ladders or other means. 3.6.2 Permanently installed access Where access to and egress from working platforms can be safely gained via permanently installed stairways, ladders or fixed platforms, such stairways, ladders or fixed platforms shall comply with AS 1657.


3.6.3 Temporary stairways Where temporary stairways are used, they shall comply with the following requirements: (a)

Stairways shall be in straight flights and not less than 500 mm wide.

(b)

The minimum vertical clearance for stairs shall be not less than 1850 mm.

(c)

The minimum vertical clearance for landings shall be not less than 1850 mm.

(d)

The length of a landing in the direction of travel shall be not less than 450 mm and the width not less than the width of the stairway.

(e)

Every access landing shall provide standing space of at least 450 mm clear of cross traffic or door swing.

(f)

Each stairway shall be provided with at least one handrail. The handrail shall extend for the length of each stairway flight or shall consist of a number of horizontal members with a maximum vertical spacing of 500 mm. NOTE: Horizontal members of the scaffold structure may form part of the stairway handrail.

(g)

The handrail shall be supported so as to allow unrestricted movement of the hand along the upper surface between support points.

3.6.4 Portable ladders Where portable ladders are used they shall be single ladders complying with the industrial-grade requirements of AS 1892.1 or AS 1892.2 in Australia or NZS 3609 or NZS 5233 in New Zealand and shall comply with the following requirements: (a)

Ladders shall be pitched at a slope of not less than one horizontally to four vertically and not more than one horizontally to six vertically.

(b)

Ladders shall be secured against displacement in any direction. COPYRIGHT

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AS / NZS 1576.1:1995

(c)

Ladders shall be provided with landings at the head and at the base; except where the ladder rests on a fully covered supporting structure, the base landing may be omitted.

(d)

Openings for ladders shall be as small as practicable and shall be adequately guarded in accordance with Clause 3.5.3.

(e)

The base of a ladder shall be offset from the head of the ladder below it, so that ladders do not take the form of a single, continuous ladder.

(f)

Ladders shall extend at least 900 mm above landings.

(g)

There shall be clear and unobstructed access to and egress from ladders at each landing.

(h)

Ladders on mobile scaffolds shall be clear of the supporting structure.

(i)

The maximum height between successive landings serviced by a portable ladder shall not exceed 6 m.

3.7

ADDITIONAL REQUIREMENTS FOR MOBILE SCAFFOLDS

3.7.1 Castors Castors shall comply with AS 1576.2 and shall be capable of being locked when work is being performed from the scaffold. 3.7.2 Supporting structure The supporting structure of a mobile scaffold shall be a hard flat surface. Unless the castors incorporate adjustable legs, the surface shall be level. Where the castors incorporate adjustable legs, the gradient of the surface shall not exceed 5 degrees, unless provision is made to take the load off the castors during use of the scaffold. 3.7.3 Additional bracing Adequate bracing in the horizontal plane shall be provided to prevent distortion of the scaffold while it is being moved. 3.8

ADDITIONAL REQUIREMENTS FOR PLATFORM BRACKETS

3.8.1 General Platform brackets shall not be used in conjunction with single pole scaffolds or suspended scaffolds. Platforms supported by platform brackets shall not be loaded with materials or equipment, unless the platform brackets have been specifically designed for such additional loads and the scaffold has been adequately braced. 3.8.2 Width of platform A platform bracket shall be capable of supporting a platform not less than 225 mm in width.


3.8.3 Positioning of brackets Platform brackets shall not be positioned between lifts of a scaffold, unless they can support a platform not less than 450 mm in width. Platform brackets shall be provided only on the face of a scaffold that is adjacent to the face of a building or other structure. 3.8.4 Provision of additional platforms Where a platform supported by brackets is provided in any bay at the lift height of a scaffold, such a bay shall be fully decked as a working platform. Where a platform supported by brackets is provided between lifts in any bay, such a bay shall be fully decked as a working platform at the lift immediately above the brackets and fully decked as a working platform at the lift immediately below the brackets, with the lower platform being provided with additional inside toeboards or equivalent edge protection. 3.9

TUBE EXTENSION A tube shall extend past the coupler by not less than 10 mm.

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As 1576.1 Scaffolding General Requirements

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