Supported Scaffolds Scaffold User Training 9% of construction deaths are scaffold-related Scaffold...

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?

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'

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 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


X & L

1” MAX

9 1/2 ”

Fully planked with scaffold-grade wood or metal.

What Makes a Safe Platform?


X & L

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


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, Square

Ladders and Scaffolds 34X & LSUBPARTS


X & L

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.


Poles, legs, posts,

frames, and

uprights plumb

and braced


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

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

Ladders and ScaffoldsX & LSUBPARTS

47

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 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

Fall Protection


48

(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.

Guardrails


49

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


53

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


54

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


54

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


58

Ladders and ScaffoldsSUBPARTS

59

Horizontal and diagonal bracing required to prevent “racking”.

Most manufacturers provide with fixed length.

Mobile Scaffolds2

X & L

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

Ladders and ScaffoldsSUBPARTS

71X & L

Supported Scaffolds Scaffold User Training 9% of construction deaths are scaffold-related Scaffold...

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