scaffold user training
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Scaffold User TrainingTRANSCRIPT
Supported Scaffolds
Scaffold User Training
9% of construction deaths are scaffold-related Scaffold falls injure 29,000 workers every year. 47% of all scaffold catastrophes and deaths are caused by defective scaffolds. Any missing or defective part
makes a scaffold less safe.
The danger of falling is most common.
Scaffold HazardsLadders and Scaffolds
1926.450 Subpart L - Scaffolds 1926.450: Scope, application and
definitions 1926.451: General requirements
– Covers the basic variables 1926.452: Specific requirements
– For each type of scaffold 1926.453: Aerial lifts 1926.454: Training
– Anyone who works from a scaffold or who erects scaffolds must have training.
Ladders and Scaffolds 15X & L
Supported scaffolds must have these features:
How Do We Know a Scaffold Is Safe?
1926.452(w) "Mobile scaffolds"
1926.452(b) “Tube & coupler scaffolds”
1926.450 definitions applicable to subpart
Competent person means one who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are hazardous or dangerous to employees, and who has the authorization to take prompt corrective measures to eliminate them.(CPL 2-1.23)
.451 General RequirementsFor All Scaffolds
(a) Capacity– Support its own weight and 4 X the
Maximum Intended Load (MIL). – Designed by a Qualified Person and built
and loaded to design.– Some Criteria listed in Appendix 'A'
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(b) Platform Construction Platforms fully planked or decked Maximum 1” gaps Maximum openings of 9½” if necessary Platforms and walkways minimum 18” wide Guardrails and/or Personal Fall Arrest
System (PFAS) for < 18” wide Planks laid at angles other than 90º laid first
under planks laid over supports at 90 º
Ladders and Scaffolds 20SUBPARTS
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1” MAX9 1/2 ”
Fully planked with scaffold-grade wood or metal.
What Makes a Safe Platform?Ladders and Scaffolds 21
SUBPARTS
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Scaffold Platform Construction Front of scaffold no more than 14 inches from face of
work For outrigger scaffolds 3 inches Unless secured platforms extend minimum of six
inches over support
6"
NOT CLEATED OR TIED(b)(7)
12”
(b)(3)
14” MAX
18”
OR MUST HAVE GUARDRAIL OR FALL PROTECTION
Platform Construction Don’t paint wood, except ID on
edges Fully planked between front
upright & guardrails Don’t mix scaffold components
used unless compatible & strength is maintained [Competent Person decision]
Don’t modify mixed scaffold components
to make them fit [C.P. decision] No components of dissimilar
metals without Competent Person approval
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X & L
Inspect, Inspect, Inspect
This 6-tier scaffold is is anchored to the building with rope through windows.
A solid strut anchor is better, especially if not dependent upon friction attachments at both ends.
Ladders and Scaffolds 30X & LSUBPARTS
Tie-Ins to the Building
1926.451 (c) Supported Scaffolds
Guys, ties or braces required at the 4:1height ratio
Repeated every 20 feet for scaffolds three feet wide or less
Every 26 feet wider than three feet Installed at each end of the scaffold Horizontal spacing not to exceed 30 feet
1926.451 (c) (1) (ii)
30 feet30 feet
You can visually check scaffold alignment.
Plumb:Vertical members stand perpendicular to horizon.
Level:Horizontal members are parallel to horizon.
Square:Horizontal and vertical members form right angles where they connect.
Plumb, Level, SquareLadders and Scaffolds 34X & L
SUBPARTS
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Foundation and Load Distribution?
Bracing required to prevent tipping for all eccentric applied loads
Scaffolds must bear on base plates and mud sills or other firm foundation
Footings rigid with no settling or displacement
Supported Scaffolds
1926.451 General Requirements(c) Criteria for supported scaffolds
(2) Base plates mud sills
Mud sills
Base plate
Unstable objects
shall not be used to
support scaffolds or
platform units.
Unstable objects
shall not be used as
working platforms.
1926.451 (c) Supported Scaffolds
Poles, legs, posts,
frames, and
uprights plumb
and braced
1926.451 (c) Supported Scaffolds
Distribute loads evenly. Point load over uprights.
Evenly distributed –A good practice!
Point Loading - When necessary, it should be done over uprights.
An unsafe practice!
What’s the Best Way to Load the Scaffold?
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1926.451 (e) Access
Scaffold more than two feet above or below a point of access ladders, stairs, ramps or other similar access provided
No cross braces for access! Hook on ladders positioned so as not to tip the
scaffold Bottom rung within 24 inches of supporting
level Over 35 feet, rest levels every 35 feet
Hook-on ladders compatible with scaffold used
Minimum rung width of 11 1/2 inches
Rungs uniformly spaced 16 3/4 inches maximum rung
spacing Slip resistant treads on stairs
and landings
1926.451 (e) Access
Prefabricated scaffold access:– specifically designed and constructed for use as ladder
rungs;– Have a rung length of at least 8 inches– Uniformly spaced– Max. spacing 16 3/4 inches
** fixed ladders must have fall protection if length of climb is 24’ or greater.**** landing ‘rest’ platforms required on fixed ladders at maximum intervals of 50’**
1926.451 (e) Access
No loading in excess of intended or rated load
Lean-to scaffolds prohibited CP to inspect for defects each shift Damaged scaffold repaired, replaced or
braced
Use
USE No makeshift devices to increase height
– The 'Drywall Bucket Rule' No ladder to increase height except on
'large area' and:– Side thrust countered, platform secured– Ladder legs on same platform & secured
Platforms not to deflect > 1/60 of span
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No moving of scaffolds with employees on them unless designed by PE for such
Must decend mobile scaffolds prior to moving, and lock casters when in position.
Safe distance from electric lines:– Insulated lines:
• Less than 300 volts = 3 feet• 300 volts to 50 kilovolts = 10 feet• Over 50 kilovolts = 10 feet plus .4 inches for each additional
kV; or twice the length of the line insulator but never less than 10 feet
Use
Scaffolds erected, moved, dismantled, or altered only under the supervision and direction of a competent person qualified in scaffolds
Access scaffolds with snow/ice only to remove
Swinging loads near scaffolds must use tag lines
Use
Debris shall not be allowed to accumulate on platforms.
Your employer must train you.
.454 Training RequirementsLadders and ScaffoldsX & L
SUBPARTS
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Required at 10 foot height PFAS instead of guardrails on some Fall protection required when scaffold is
greater than 14” away from work surface PFAS for erectors/dismantlers where
feasible Toprails height = 38” to 45” Crossbracing ‘X’ as top or midrail
depending on height
Fall ProtectionLadders and ScaffoldsX & L
SUBPARTS
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(g)(4)(xv)
48” Max
Mid 20”- 30”
Top38”- 40”
Cross bracing in Guardrail Systems
Guardrails prevent work falls.
─ Ideal height is 38 inches above work platform.─ OSHA requires fall protection on platforms 10 feet or higher.
Top rail must withstand a force of 200 pounds (or 100 pounds on suspension scaffolds).
Only 33% of the scaffolds involved in accidents had guardrails.
GuardrailsLadders and ScaffoldsX & L
SUBPARTS
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1926.451 (g) Fall Protection
Guardrail systems shall be installed along all open sides and ends of platforms.
Guardrail systems installed before scaffold is released for use by employees other than erection/dismantling crews.
(h) Falling Object Protection Hardhats required Protect employees below Barricades to exclude working below Toe boards at edges of platforms Allows panels and screens Canopies allowed
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Using extra planks on edge:– Wire in place– Maintain max. gap of ¼"– Wire or nail ends in place
Job-made w/1"x 6" lumber:– Wire/nail/cleat in place– Lighter, easier to handle
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Toeboard Options
Scaffolds shall remain a minimum of 10 feet away from energized power lines.
All power tools and equipment shall be plugged into a GFCI
Temporary lighting shall not be connected to the scaffold system by metal components
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Electrical Hazards
Mobile Scaffolds3
Plumb; Level square; Braces secured Cross, horizontal & diagonal braces to
prevent racking or collapse Mobile scaffolds must comply with other
frame requirements Castors - positive lock on wheel and/or
swivel
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Horizontal and diagonal bracing required to prevent “racking”.
Most manufacturers provide with fixed length.
Mobile Scaffolds2
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Bricklaying crew working on the upper floor of a three-story building built a six-foot platform spanning a gap between two scaffolds. The platform was correctly constructed of two 2”X12” planks with standard guardrails; however, one of the planks was not scaffold grade lumber and also had extensive dry rot in the center. when a bricklayer stepped on the plank it disintegrated and he fell 30 feet to his death.
Fatal fact
Two employees were installing aluminum siding on a farm house when it became necessary to remove a 36-foot high metal pole CB antenna. One employee stood on a metal pick board between two ladders and unfastened the antenna at the top of the house. The other employee who was standing on the ground, took the antenna to lay it down in the yard. The antenna made electrical contact with a 7200-volt power transmission line 30 feet 10 inches from the house and 23 feet 9 inches above the ground. The employee handling the antenna received a fatal shock and the other employee a minor shock.
Fatal fact
Don’t allow tools, materials, or debris to collect on scaffold.
Never, never throw or drop tools, materials, or equipment.
Make sure connections are in place and completely tight.
Do not stand on ties. Do not stand on guardrails or plank
extensions. Do not overreach outside of the guardrails.
Protect Yourself With Good Practice
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71X & L