Supported Scaffolds

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 Hazards

Ladders 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?

.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'

Ladders and Scaffolds 17SUBPARTS

X & L

(b) Platform Construction

Platforms fully planked or decked

Maximum 1” gaps

Maximum openings of 9½” if necessary

Platforms and walkways minimum 18” wide Ladder jack, top plate bracket, roof bracket,

and pump jack scaffold at least 12” wide Guardrails and/or Personal Fall Arrest

System (PFAS) for < 18” wide


X & L

Fully planked with scaffold-grade wood or metal.

What Makes a Safe Platform?


X & L

(b) Platform Construction4

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


X & L

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

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, Square

Ladders and Scaffolds 34X & LSUBPARTS


X & L

Foundation and Load Distribution?

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?


X & L

.451(e) Access Must have safe access

– No access by cross braces– Bottom rung not more than 24” high– From other surface if within 14" H, 24" V– Rest platforms at 35’ intervals– Safe access for erectors/dismantlers

• Competent Person Decision• 22" Horizontals OK for Builders

Some end frames can be used for access.

Ladders and ScaffoldsSUBPARTS

38X & L

(f) USE3

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

Ladders and ScaffoldsX & LSUBPARTS

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Your employer must train you.

.454 Training Requirements


73

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

.451(g) Fall Protection


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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.

Guardrails


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(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 Force to move no more than 5 feet above

base


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59

Horizontal and diagonal bracing required to prevent “racking”.

Most manufacturers provide with fixed length.

.452(w) Mobile Scaffolds2

X & L

Mobile Scaffolds4

No platforms beyond base unless outriggers or equivalent for stability

Screwjacks or equivalent to level

Castor stems pinned or bolted

Make workers aware before moving


60X & L

Mobile Scaffolds4

Stabilize to prevent tipping when moving No riding unless:

– Surface within 30 of level; no obstructions– Height: base width ratio = 2:1 or designed– Outriggers, if used, on both sides– No extensions beyond supports– Power used < 1 foot/second


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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


71X & L

Supported Scaffolds

Documents

Transcript of Supported Scaffolds