Scaffolding highlight
Scaffolds cause THOUSANDS of accidents and kill HUNDREDS of workers every year Most of the injuries involved in scaffold accidents were caused by either the planking or support giving way, or to the employee slipping or being struck by a falling object. Plank slippage is apparently the most common cause of serious accidents.
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Typical Hazards Typical hazards associated to scaffolding activities are:
People and objects falling from height Electrical shocks shocks from power lines or use of electrical equipment attached to scaffold Use of equipment/mac equipment/machinery hinery for material lifting Reduced lighting levels Poor access-egress/si access-egress/simultaneous multaneous activities/congested activities/conge sted areas: slips, trips, contacts Collapse / improper material and design / improper modification Dizziness / strong wind / overloading Slips, trips, falls, etc.
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Typical Hazards
Poor Po or ini initia tiall de desig sign n Inadequate bracing Overloading Deteriorated or faulty fittings or materials Unauthorized alteration Impact from passing vehicles Failure of the structure when incomplete Falls of scaffolders !!! Scaffolding materials being dropped
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Supported Scaffolding
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Mobile
r a m e or a r c a e Tube and Coupler
Wooden
Bracket Scaffold
Supported Scaffolding
Structure Supporting Scaffold & Cantilever Scaffold
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Basic Scaffold Scaffolding is a temporary framework used to support people and material in construction or repair activities. It is usually a modular system of metal pipes, although it can be made out of other materials. Wood is still used frequently A. SCAFFO SCAFFOLD LD PLANKS PLANKS (BOA (BOARDS RDS)) B. BE BEA ARE RER R (TRA (TRANS NSOM) OM) C. LONGI LONGITUDI TUDINA NAL L (F (FACA ACADE) DE) BRACING D. TRA TRANSV NSVERS ERSE E (SECTION (SECTIONA AL) BRACING E. TOPRAIL F. MIDRAIL G. TOE OEBO BOA ARD H. POS POST T (ST (STAN ANDAR DARD) D) I. RUNNER (LEDGER) J. BA BASE SE PL PLA ATE K. SI SILL LL (S (SOL OLE E BOARD BOARD)) L. SEL SELF-C F-CLOS LOSING ING DRO DROP P BAR BAR (INSIDE (INSIDE POSTS) M. BA BASE SE LIFT LIFT (KIC (KICKER KER LIFT) N. FAL ALSE SE UPRIGH UPRIGHT T (PUNCHE (PUNCHEON) ON) O. COUPLER
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Scaffold Duty and Safe Factor
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Scaffold shall be designed and/or constructed for a s specific pec pe cif ific ic purpose and loading. loading. Here examples of typical applications: Duty D uty of of Platform Platform
Typical Typical u use se o off P Platform latform
Max Distributed Load on Platform kg/m2
Very light
Inspection, Painting, Cleaning and Access
75
Light
Painting - Cleaning
150
General Purpose
General Construction Work
200
Heavy
Heavy Construction
250
Special
Very Heavy Construction
300
The scaffold shall support 4 times times the the maximum intended load
Scaffold Material and Manufactures Instruction
Cannot intermix c Cannot components omponents from different manufacturers unless com co mpatible and int nte egr griity is main inttain ine ed Tubes, units, frames, clamps, etc. shall be of the suitable suit ita abl ble e th thic ick kne nes ss, s straight trai tr aig ght and shall be free of cracks, s and splits, plits, exces exc excessive essi sive ve cor corros corr co rros rosion osio ion n or or ot othe other her defects. defe de fect cts s. Tubes requiring consistent maintenance such as brushing or scraping shall be replaced. The only acceptable tubes coating is the No ttubes ubes galvanizing and zinc primer. No will b will be e ot othe herwi rwis rwise s se e pa pain painted inte ted d
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Basic Scaffold Components
Starting with a Solid & Flat Base is possibly the most important step when erecting scaffold First inspect the area and make the surface level • The ground or surface must be capable of supporting the scaffold and the imposed load • The ground or surface under the standards must be made as level as possible • Getting the base right, saves time and effort and is critical for the stability of the scaffold
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Solid and Flat Base
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No!!! Yes!!!
Solid and Flat Base
Be sure of what’s below !!!
C
Back Fill Sewer
Incorrect
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Base Plate and Sole Board
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Scaffold shall be plumb !!!! At least 15x15 Steel Base Plate
Base Plate Individual Sole Board
Sole Boards
Sole Boards are lengths or pieces of timber that are placed underneath the standards bases to spread the load Always used with a metal base ba se pl plat ate e Must always be placed on flat and even ground Try to get more than one standard on each sole board They must be strong and thick enough to support the entire we weig igh ht of the scaffold
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Base Plate and Sole Board
Improper Placement
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Base Plate and Sole Board
Improper Placement of scaffolds sc affolds can cause direct and indirect problem at site till to arrive to possible collapse of scaffold and/or ground
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Planking
Metal planks shall be preferably used. Wooden planks may be allowed, but planks shall meet quality material and shape standard Wooden material for scaffolding,, treated for long scaffolding term exposure and climatic conditions, free of knots, cracks, splits or damage and with banded ends. Planks shall be at least a standard size (5 cm thick and 20 cm wide), wide), flat and not warped
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Plank Inspection
The p The plan pl la anks nk ks s qu qual alit ity y sh shal shall all be c chec ch he ecke ck ked ed be befo fore re en ente ent nter teri erin ring ing ng g th the the site an and and pe peri periodically riod odic ical ally ly the there here re a after. fter ft er. Both ends of the approved planks should be marked with colour paint, and shall not be painted or treated in any other way that may conceal defects. Scrap or Scrap or un unsu suit itab able le bo boar ards ds sh shal shall all not be used a as s sc scaf affo fold lds s pl plan planks, planks anks ks, but may be use or oe oar s or s or ma e-up oar s. ey s ou e mar e w eren colo co lour ur pa pain int. t. Scaf Sc Scaffold affol fold d bo boar boards boa ards rds ds s shal sh hall ha alllll n not no ot be used fo for for ot othe oth her herr pu purp rpos ose ea and an nd vicevice-versa -versa
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Components Thickness and Resistance
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Standards and Ledgers
Standards are vertical tubes that serve as vertical legs and compression (load) supports
Ledgers are tubes that tie the standards together
Ledgers
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Standards
Transom
Transo Tra nsom m are horiz horizont ontal al tubes tubes that tie tie standards together at right angles to the ledgers
The transoms that support the work platform must always be placed on top of the ledgers: if not and one clamp fail, this can cause the work platform to fall
Intermediate Transom
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Bracing Example
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Bracing Example
Properly placed sway bracing, transoms and check clamps…
Check Clamps
Sway Brace
Transoms
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Junction Systems
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Tube and Coupler, embossed or forged marking are acceptable
Cup locks
Kwikstage
Work Platform
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Work Platform is the boarded area that is used as an access and/or working area with toe boards and hand rails in place
ALL BOARDS OR PLANKS USED FOR ANY SCAFFOLD MUST ALWAYS BE SECURED BY MECHANICAL/ METAL MECHANISM OR THE USE OF WIRE
Hand rail and Toe board to be fixed to the insi in inside side de of th the e support standard
Work Platfor Platform m – Guard Rail Rail and Toe Toe Board Falls Protectio Protection n
Guard Rails (middle 0.5 m and upper 1.0 m from the platform) are horizontal tubes fixed to the uprig uprights hts that preve prevent nt the users from falling from the work platform
Uprights Toe Boards are lengths of vertically placed timbers/planks (no less than 20 cm high) to ensure that tools, equipment and materials stay on the work platform work
NOTE: TOE BOARD NOT REQUIRED FOR INTERNAL SIDE OF SCAFFOLD CLOSER THAN 25 cm FROM A WALL
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Tie Methods
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Tie Methods
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Tie is a method of connecting a scaffold to a fixed structure to prevent the scaffold from falling over
Box Tie Through Tie
Recapitulation
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Access
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Access rroute Access oute shall be provided for each working platform by ladder, stair, ramp or walkway, based on a sound footing. Home made ladders are prohibited.
Ladders
Stair S tair Tower Tower
D Direct irect A Access ccess
Improper Access
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Route
This photo shows several unsafe condition, condi tion, but remind also that the preferably direction change of scaffold route is the right angle
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Access
Climbing of scaffold braces, runners, etc. is not permitted, except as required by scaffold craftsmen during scaffold erection, alteration, and dismantling. Proper access to be erected and used
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Access by Ladders
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Mobile Scaffolds
Mobile tower scaffolds shall be erected and used as per manu ma nufa fact ctur ure e in inst stru ruc cti tion ons s, supported on four wheels with wi th suit ita able bra rak kes and with one safe working platform Such kind of scaffolds shall be used up to 12 meters, with a safe access prefarably by internal ladder ratio o off 3 3::1 :1 Maximum height to minimum base width ratio plumb, level and b braced raced to prevent collapse or Shall be plumb, racking. Use it only on firm and strong surfaces. ee ra es s a e e app e a ways w en scaffold is not in motion and a man is on it Am mobi mo ob bile ille e sc scaf scaffo aff ffo fold old ld can be moved only ly when nobody iis s on iitt and by pushing or pulling it at the base: remove all on materials and equipment prior to moving it, ensure the route is clear, watching for holes and overhead obs bstr truc ucti tion ons s (d (dan ange gero rous us el elec ectr tric ical al liline nes, s, et etc c.) .)..
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Mobile Scaffold DO NOT MOVE MOBILE SCAF SCAFFOLDING FOLDING WITH PERSON ON BOARD PUSHING/PULLING IT AT THE BASE AND PAY ATTENTION TO OVERHEAD LIVE ELECTRICAL CABLE
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Slipping / Tripping / Material Falls
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Housekeeping shall be maintained to prevent slips, trips and falls Access-ways should be kept clear of tripping hazards Spills, mud, scrap and other debris to be cleared-up immediately All chords, leads, hoses, etc. shall, if possible, be supported above walkways and platforms by non-conductive material Supplies and materials should be stacked to a height as low as practical without exceeding load capacity Secure loose or light materials to prevent them from falling Use container to store small objects and secure the container Always push, do not pull objects. objects . Block & chock cylindrical objects Be alert to wind forces when handling materials at heights Do not leave loads suspended. Use tag lines to guide loads.
Falling Object Protection
In addition to wearing hardhats, more protection from falling objects may be provided by: Barricading not permitting area below into which objects can fall , platforms, or canopy structures sufficient to catch falling objects, or Applying safe practices to prevent falls: tool pockets, tool tied-off, buckets, etc.
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Falls Protection Guardrail systems shall be able to withstand a force of at least 90 Kg applied in any downward or horizontal direction at any point Guardrail systems shall be installed before an elevated work area may be used by anyone other than the scaffold craftsmen Where a complete guardrail system cannot be implemented implemented,, a personal fall arrest system shall be con contin continuously tinuou uously sly use used d by anyo anyone ne on an elevated elevated elev ated work area or platform. platform. A personal fall arrest system includes a full body harness, lanyard, lanyard, connectors, substantial substantial anchorage(s) and possible lifeline At no time shall body belts or safety belts be used as part of a personal fall arrest system: five points contact harnesses properly worn w orn is right!
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Falls Protection
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Distance from The Face of The Work
Scaffold shall be erected close to the structure where the work has to be executed (generally no more than 30-40 cm from the face of the work). In case of more distance a safet harnesses s shall hall b be e worn at all time while on scaffolding (known also as YELLOW TAG scaffolding) This condition is typical for example during the initial phase of insulation activities
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Hazard Highlight: WIND
Be careful of wind condition while on scaffold: the wind force shall be considered when projecting a scaffold anchor points and stability system, particularly in case of the use of safety net, shields, etc. and it shall be considered also in case during the use of scaffold: working at height during strong wind is always more hazardous than in normal condition Wind can overturn scaffold or make it colla sin
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Hazard Highlight: Electricity
Electrocution can be very dangerous at height due to direct possible effect or due to possible falls Generally when electrical apparatus shall be installed on scaffold, it shall be gorunded always between conductive equipment / scaffolds and power lines: at least 5 m till 50kV, then shall be increased proportionally.. If needed, barrier proportionally erection with insulated material can be useful too
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Hazard Highlight: Electricity
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Special Scaffold Shall Be Designed
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Scaffolds Tags TAGGING SYSTEM SY STEM IDENTIFI IDENTIFIES ES THE CURRENT ST STA ATUS OF THE EXISTING SCAFFOLD:
RED – – DO NOT USE
GREEN – – PASSED INSPECTION : SAFE FOR FOR USE AT TIME OF INSPECTION
YELLOW – – FULL BODY HARNESS REQUIRED REQUIRED
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Red Tag
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Red tag means scaffold under construction, modification, incomplete, dangerous, etc.
Scaffold not tagged, regardless of reason, s a e assumed to be "UNSAFE FOR USE."
Any red tagged scaffold shall not be used, except by scaffold craftsmen that are fall protected for the , dismantling, altering, or correcting scaffold deficiencies. Unauthorized person using a Red tagged scaffold will be disciplined
Green Tag
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Green tag means scaffold completed and accepted for use. Scaffolds Green tags shall be attached at some point near the acces acc ess s la ladd dder er where it is visible to anyone climbing the ladder.
Green tags shall have a maximum validit till next inspection (generally one week).
Nobody shall access a scaffold unless it has been tagged GREEN GREEN,, the signature is visible and the user,, himself, is satisfied about the structure. user
Yellow Tag
May indicate that scaffold has been inspected and may be used only by workers wearing a properly anchored personal fall arrest system, including a full body harness and lanyard (see example pag.64)
Back of Green Tag is Generally Utilize as Tag Inspection Space
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Scaffolders
Only skilled scaffolders supervised by a Competent Person are allowed to construct, modified or dismantling scaffold
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Scaffolder: 100% Fall Protection
Climb scaffold maintaining 100% 100 % fall protection Safety harnesses with two lanyards shall be used at all time. Any other needed fall protection devices (independent lifeline, self arrest equipment, etc.) shall be used to guarantee 100% tied off and to minimise falling hazards
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Scaffold Construction
Before the erection starts, the scaffolding material shall be inspected to ensure that it is of the right type and it is in suitable condition. A safe area shall be established around the construction place by means of proper signs, plastic tape, barr ba rrie iers rs,, et etc. c. During erection a RED tag shall be affixed to the scaffold at each access point.
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Scaffold Construction
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Hand Over
Only a scaffold Competent Person/Supervisor or Inspector is authorized to finally check the scaffold, indicate eventual rectifications , , to remove RED tags for hand over to users and its final acceptance, so determining GREEN tag status
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Scaffold Use
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Scaffold users shall utilise the scaffold in a safe manner maintaining always a safe sa fe cl clea eara ranc nce e of co cond nduc ucti tive ve eq equi uipm pmen ent/ t/ma mate teri rial al fr from om po pow wer liline nes s Utililis Ut ise e alw lway ays s th the e att tta ach ched ed la lad dde ders rs or the other safe access foreseen Jumping from one scaffold to another is prohibited. Climbing scaffolding on its exte ex teri rior or pe peri rime mete terr is st stri rict ctly ly pr proh ohib ibit ited ed.. Sca cafffo fold ld/c /com ompo pone nent nts s sh shal alll not be lo loa ade ded d in exce ces ss of their max inte ten nded loads. The Th e pl plat atfo form rm sh shal alll no nott vi visi sibl bly y/e /ex xce cess ssiv ivel ely y de defl flec ectt whe hen n lo load aded ed.. No st stoc ockp kpililed ed Main Ma inta tain in th the e scaffold free of rubbish clear of tools and materials oil- rease etc. Tool ols s/m /ma ate terria ials ls ar are e not to be th thro row wn: never! Hand Han d lin lines/ es/buc bucket kets s to be us used ed fo forr rais isin ing/ g/lo low weri rin ng lilig ght han and d to too ols ls/e /equ quip ipm men entt Windscreens shall not be used if scaffold has not designed for those devices Makeshift work platforms not be used on scaffold to increase the work height Ladders to increase workin ing g level heig igh ht only if allow owe ed on large area scaffolds All work in height might be stopped in bad weather, storms or high wind speeds Modifi Mod Modified ified ed sca scaffo scaf sc affo ffold fold ld is pr proh ohib ibit ited ed to to tth the he us use users ers
Scaffold Use
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Scaffold Inspection All scaffolds shall be inspected initially to determine the green tag status and then regularly, regularly, generally weekly recorded on the tag, tag, and after adjustments, modifications, adverse weather conditions, etc. by a Competent Person. Person. Continuous inspection shall be done by users, inspectors, HSE staff, staff, etc. to verify verify that the scaffo scaffolds lds have not been been altered and are in a safe safe working condition.
seems a e sca o s unsafe then the Scaffold Supervisor shall be immediately informed
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Scaffold Dismantling
All scaffolds shall be dismantled only under under tth the he di dire rect rec ctio cti tio ion on of the S the Scaf Sc ca affo fffold old Su Supe Supervisor: perv rvis isor or: he ensures that the GREEN tag is removed from the scaffold and that a RED RED tag tag is securely affixed at each point of access. Only trained trai tr aine ned d an and d exp experi erienc enced ed sca scaffo ffold ld cra crafts craftsmen ftsme men n can do it Dism Di Dismantling sman antl tlin ing g sh shal shall all be p planned, planned lanned, orderly, and performed level by level from from top to bo bot bottom. bottom tto tom m. Scaf Sc Scaffold affo fold ld co comp mpon onen ents ts,, to tool tools, ols, s, e etc. tc. shall be llowered owe werred to the , . Are Area rea a und undern unde un dern erneat rnea eath th h sha shall shall ll be be ffe fenc ence en nced ced ed d an and d co cont controlled ntro rolle lled d Scaffold materials shall be inspected, returned and properly stacked at their designated storage location immedi imm ediate ately ly aft after er
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Independents scaffold shall always be built on firm level ground
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To achi achiev eve e leve levell grou ground nd al alwa ways ys rem remov ove e soil soil rat rathe herr tha than n bui build ld up up
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Only au Only auth thor oriz ized ed tr trai aine ned d sca scafffo fold lder ers s ca can n er erec ect, t, di dism sman antl tle e or al alte terr scaffolding - it is forbidden forbidden for for any other other person person to do this this
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All scaffolds must be built to Local Local Code Code or a highe higherr Standard Standard without exception
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Barriers must be erected around any scaffold that is being erected, dismantled or altered
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INCREASE YOUR SAFETY SENSATION…
