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A guide to SAFE SCAFFOLDING

Industry
Guide

38
A Guide to
Safe Scaffolding

N.C. Department of Labor

N.C. Department of Labor
Occupational Safety and Health Division
1101 Mail Service Center
Raleigh, NC 27699-1101
Cherie Berry
Commissioner of Labor


N.C. Department of Labor
Occupational Safety and Health Program
Cherie Berry
Commissioner of Labor

OSHA State Plan Designee
Allen McNeely
Deputy Commissioner for Safety and Health
Kevin Beauregard
Assistant Deputy Commissioner for Safety and Health
Bobby Davis
Reviewer

Acknowledgments
A Guide to Safe Scaffolding was initially prepared for the N.C. Department of Labor by David L. Potts. Mr. Potts has
written extensively about subjects regarding construction safety and is a recognized authority in safe scaffolding. The
information in this guide was reviewed in 2011.
_____
The N.C. Department of Labor is grateful to the Scaffolding Industry Association for permission to use the illustrations
in this guide.
_____
This guide is intended to be consistent with all existing OSHA standards; therefore, if an area is considered by the
reader to be inconsistent with a standard, then the OSHA standard should be followed.

To obtain additional copies of this guide, or if you have questions about N.C. occupational safety and health standards or
rules, please contact:
N.C. Department of Labor
Education, Training and Technical Assistance Bureau
1101 Mail Service Center
Raleigh, NC 27699-1101
Phone: 919-807-2875 or 1-800-NC-LABOR (1-800-625-2267)

____________________
Additional sources of information are listed on the inside back cover of this guide.

____________________
The projected cost of the NCDOL OSH program for federal fiscal year 2011–2012 is $17,841,216. Federal funding provides approximately 31 percent ($5,501,500) of
this total.
Revised 2/11


Contents
Part

Page
Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1iiv

1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ivi1

2

Policy for Safe Scaffold Erection and Use . . . . . . . . . . . . . . . . . . . . . . . . . . . .ii12

3

Illustrations of Selected Types of Scaffolds . . . . . . . . . . . . . . . . . . . . . . . . . . .ii16

4

Types of Scaffolding and Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ii22
Glossary

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii30

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ii32

iii


Foreword
Scaffolding can provide an efficient and safe means to perform work. However, unsafe scaffolding procedures can lead
to accidents, serious injuries and death. This guide makes clear that planning ahead for the erection, use and dismantling
of scaffolding can substantially reduce scaffold-related accidents and injuries. Compliance with the manufacturer’s
instructions, the use of this guide and compliance with all scaffolding standards will help ensure a safer workplace for
employees.
Safety and health in the workplace is everyone’s responsibility. Employers must be aware of workplace hazards facing
their workers, and they must take appropriate action to minimize or eliminate exposure to these hazards. Workers are
responsible for following the policies, procedures and training requirements established by their employers. A Guide to
Safe Scaffolding discusses precautions that can prevent serious accidents and protect workers against fall injuries and
fatalities.
In North Carolina, the N.C. Department of Labor enforces the federal Occupational Safety and Health Act through
a state plan approved by the U.S. Department of Labor. NCDOL offers many educational programs to the public and
produces publications to help inform people about their rights and responsibilities regarding occupational safety and
health.
When reading this guide, please remember the mission of the N.C. Department of Labor is greater than just regulatory
enforcement. An equally important goal is to help citizens find ways to create safe workplaces. Everyone profits when
managers and employees work together for safety. This booklet, like the other educational materials produced by the
N.C. Department of Labor, can help.
Cherie Berry
Commissioner of Labor

v


1
Introduction
Scaffolding has a variety of applications. It is used in construction, alteration, routine maintenance and renovation.
Scaffolding offers a safer and more comfortable work arrangement compared to leaning over edges, stretching overhead
and working from ladders. Suitable and sufficient scaffolding must be supplied for work at elevations that cannot be
accomplished safely by other means. Properly erected and maintained, scaffolding provides workers safe access to work
locations, level and stable working platforms, and temporary storage for tools and materials for performing immediate
tasks.
Accidents involving scaffolding mainly involve people falling, incorrect operating procedures, environmental conditions and falling materials caused by equipment failure. The causes of scaffolding accidents include failures at attachment
points, parts failure, inadequate fall protection, improper construction or work rules, and changing environmental conditions (high winds, temperature extremes or the presence of toxic gases). Additionally, overloading of scaffolding is a frequent cause of major scaffold failure.
Individuals exposed to scaffolding hazards include scaffold erectors and dismantlers, personnel working on scaffolds,
and employees and the general public near scaffolding. Scaffold erectors and dismantlers are at particular risk, since they
work on scaffolds before ladders, guardrails, platforms and planks are completely installed.
This guide IS NOT INTENDED to be a guideline for compliance with all pertinent regulations enforced under the
Occupational Safety and Health Act of North Carolina, but rather an overview of safe practices in scaffolding procedures.
Though the guide is not intended to be inconsistent with adopted standards, if an area is considered by the reader to be
inconsistent, the applicable standard should be followed.

1


2
Policy for Safe Scaffold Erection and Use
Safe scaffold erection and use should begin by developing policy and work rules. Policy and work rules should
concentrate on:
l

sound design

l

selecting the right scaffold for the job

l

assigning personnel

l

training

l

fall protection

l

guidelines for proper erection

l

guidelines for use

l

guidelines for alteration and dismantling

l

inspections

l

maintenance and storage

Sources of information for policy development and work rules include OSHA and ANSI standards, scaffold trade associations, scaffolding suppliers, and safety and engineering consultation services.

Sound Design
The scaffold should be capable of supporting its own weight and at least four times the maximum intended load to be
applied or transmitted to the scaffold and components. Suspension ropes should be capable of supporting six times the
maximum intended load. Guardrails should be able to withstand at least 200 pounds of force on the top rail and 100
pounds on the midrail. On complex systems, the services of an engineer may be needed to determine the loads at particular points.

Selecting the Right Scaffold for the Job
You cannot contract away the responsibility for selecting the right scaffold for your job. But if you do contract for
scaffolding:
l

Choose a scaffold supplier, rental agency and/or erector who is thoroughly knowledgeable about the equipment
needed and its safe use.

l

Obtain the owner’s manual prepared by the scaffolding manufacturer, which states equipment limitations, special
warnings, intended use and maintenance requirements.

If you are to select your own scaffold, begin by reviewing the written requirements (blueprints, work orders, etc.) to
determine where scaffolds should be used and the type of scaffolding needed. Make sure that the scaffolds meet all government and voluntary requirements. Consider that scaffolds are generally rated light, medium and heavy duty. Light duty
scaffolds can support a limited number of employees and hand tools. Medium duty scaffolds must be capable of safely
holding workers, hand tools and the weight of construction materials being installed. Heavy duty scaffolds are needed
when the scaffold must sustain workers, tools and the weight of stored materials.
Account for any special features of the building structure in relationship to the scaffold, including distinctive site conditions. Factor these considerations into your policy:
l

experience of erection and working personnel

l

length and kind of work tasks to be performed

l

weight of loads to be supported

l

hazards to people working on and near the scaffolding
2


l

needed fall protection

l

material hoists

l

rescue equipment (particularly for suspended scaffolds)

l

weather and environmental conditions

l

availability of scaffolding, components, etc.

Assigning Personnel
Assign a competent person to oversee the scaffold selection, erection, use, movement, alteration, dismantling, maintenance and inspection. Only assign trained and experienced personnel to work on scaffolding. Be certain they are knowledgeable about the type of scaffolding to be used and about the proper selection, care and use of fall protection equipment
(perimeter protection, fall protection/work positioning belts and full harnesses, lanyards, lifelines, rope grabs, shock
absorbers, etc.).

Training
Employees should receive instruction on the particular types of scaffolds that they are to use. Training should focus on
proper erection, handling, use, inspection, removal and care of the scaffolds. Training must also include the installation of
fall protection, particularly guardrails, and the proper selection, use and care of fall arrest equipment.
The competent person(s) should receive additional training regarding the selection of scaffolds, recognition of site conditions, scaffold hazard recognition, protection of exposed personnel and the public, repair and replacement options, and
requirements of standards.
Site management personnel should also be familiar with correct scaffolding procedures so they can better determine
needs and identify deficiencies.

Fall Protection
Guardrails must be installed on all scaffold platforms in accordance with required standards and at least consist of top
rails, midrails and toeboards (if more than 10 feet above the ground or floor). The top edge height of toprails or equivalent
member on supported scaffolds manufactured or placed in service after Jan. 1, 2000, shall be installed between 38 inches
and 45 inches above the platform surface. The top edge height on supported scaffolds manufactured and placed in service
before Jan. 1, 2000, and on all suspended scaffolds where both a guardrail and a personal fall arrest system are required
shall be between 36 inches and 45 inches. When it is necessary to remove guardrails (for example, to off-load materials),
supervision must ensure that they are replaced quickly.
Hard hats should be worn to protect against falling objects. Mesh, screens, intermediate vertical members or solid panels should be used to safeguard employees and the public at lower levels. Ground-level safety can be further provided by
erecting canopies; by prohibiting entry into the fall hazard area by policy, barricades and signs; and by the proper placement of materials, tools and equipment on scaffolding.
Workers on suspended scaffolds must use a fall arrest system as protection against the failure of the scaffold or its components. This system will usually consist of a full body harness, lanyard, rope grab, independent vertical lifeline and an
independent lifeline anchorage.
The full body harness is a belt system designed to distribute the impact energy of a fall over the shoulders, thighs and
buttocks. A properly designed harness will permit prolonged worker suspension after a fall without restricting blood flow,
which may cause internal injuries. Rescue is also aided because of the upright positioning of the worker.
A lanyard connects the safety harness to the rope grab on the lifeline. Materials should be made of 5⁄8-inch nylon rope
or nylon webbing. Lanyards shall be kept as short as possible to limit fall distance or rigged such that an employee can
never free fall more than 6 feet.
Rope grabs contain a cam device that locks onto a lifeline when there is a hard tug or pull on the lanyard. Care must be
taken to ensure that rope grabs are properly connected to lifelines so the cam will work correctly. Rope grabs should be
placed at the highest point on the lifeline to reduce the fall distance and unintentional disengagement.
3


Independent vertical lifelines (not scaffold suspension lines) of fiber rope should be used for each person working on
the suspended scaffold. In the presence of flame or heat, wire rope lifelines should be used with lanyards containing
shock absorbers. Vertical lifelines should extend from the anchorage point to the ground or a safe landing place above the
ground.
It is important to remember that fall protection is only as good as its anchorage. The anchorage points are independent
points on structures where lifelines are securely attached. These points must be able to support at least 5,000 pounds per
employee and preferably 5,400 pounds for a fall of up to 6 feet or 3,000 pounds for a fall of 2 feet or less.

General Guidelines for Proper Erection
Accidents and injuries can be reduced when the guidelines in this section are followed.
Supervise the erection of scaffolding. This must be done by a person competent by skill, experience and training to
ensure safe installation according to the manufacturer’s specifications and other requirements.
Know the voltage of energized power lines. Ensure increased awareness of location of energized power lines; maintain
safe clearance between scaffolds and power lines (i.e., minimum distance of 3 feet for insulated lines less than 300 volts;
10 feet for insulated lines 300 volts or more). Identify heat sources like steam pipes. Anticipate the presence of hazards
before erecting scaffolds and keep a safe distance from them.
Be sure that fall protection equipment is available before beginning erection and use it as needed. Have scaffolding
material delivered as close to the erection site as possible to minimize the need for manual handling. Arrange components
in the order of erection.
Ensure the availability of material hoisting and rigging equipment to lift components to the erection point and eliminate the need to climb with components. Examine all scaffold components prior to erection. Return and tag “Do Not Use”
or destroy defective components.
Prohibit or restrict the intermixing of manufactured scaffold components, unless: (1) the components fit together properly, without force, (2) the use of dissimilar metals will not reduce strength, and (3) the design load capacities are maintained.
All scaffold decks should be planked as fully as possible (beginning at the work surface face) with gaps between
planks no more than 1 inch wide (to account for plank warp and wane). (Figure 1 shows types of planking.) The remaining space on bearer member (between the last plank and guardrail) cannot exceed 91⁄2 inches (the space required to install
an additional plank). Guardrail systems are not required on the building side when the platform is less than 16 inches
from the building, except for suspended scaffolds where the maximum distance is 12 inches. In addition, scaffold setbacks will depend upon the needs of the trade. As an example, masons require the scaffold platform to be as close to the
wall as possible (within 6 inches), while lathers and plasterers using spraying apparatus must stand back (and prefer a setback distance of at least 18 inches). Platform units must not extend less than 6 inches over their supports unless they are
cleated or contain hooks or other restraining devices. When platform units are abutted together or overlapped to make a
long platform, each end should rest on a separate support or equivalent support. Wood preservatives, fire retardant finishes and slip-resistant finishes can be applied to platform units; however, no coating should obscure the top and bottom of
wooden surfaces. If fire retardants are used, an engineer should ensure that the plank(s) will carry the required load since
fire retardants can reduce the plank load capacity.
Provide suitable access to and between scaffolds (see Figure 4). Access can be provided by portable ladders; hook-on
ladders; attachable ladders; stairway-type ladders; integral prefabricated scaffold rungs; direct passage from another scaffold, structure or personnel hoist; ramps; runways; or similar adequate means. Crossbraces and scaffold frames shall not
be used for access scaffold platforms unless they are equipped with a built-in ladder specifically designed for such purpose. All ladders in use must meet OSHA specifications, designed according to standards and secured against displacement. The bottom steps of ladders must not be more than 2 feet from the supporting level. Rest platforms are recommended for at least every 30–36 feet of elevation. When direct access is used, spacing between scaffold and another surface
should be no more than 14 inches horizontally and 2 feet vertically.
Additional recommendations for the erection of supported scaffolds, suspension scaffolds, fabricated frame scaffolds,
outrigger scaffolds, etc., are also described in this booklet.

4


Guidelines for Use
l

Be certain that scaffolds and components are not loaded beyond their rated and maximum capacities.

l

Prohibit the movement of scaffolds when employees are on them.

l

Maintain a safe distance from energized power lines.

l

Prohibit work on scaffolds until snow, ice and other materials that could cause slipping and falls are removed.

l

Protect suspension ropes from contact with sources of heat (welding, cutting, etc.) and from acids and other corrosive substances.

l

Prohibit scaffold use during storms and high winds.

l

Remove debris and unnecessary materials from scaffold platforms.

l

Prohibit the use of ladders and other devices to increase working heights on platforms.

Guidelines for Alteration and Dismantling
l

Require that scaffolds be altered, moved and dismantled under the supervision of a competent person.

l

Alteration and dismantling activities should be planned and performed with the same care as with erection.

l

Tag any incomplete scaffold or damaged component out of service.

Inspections
Inspect all scaffolds and components upon receipt at the erection location. Return, tag “Do Not Use” or destroy defective components. Inspect scaffolds before use and attach a tag stating the time and date of inspection.
Inspect scaffolds before each workshift and especially after changing weather conditions and prolonged interruptions
of work. Check for such items as solid foundations, stable conditions, complete working and rest platforms, suitable
anchorage points, required guardrails, loose connections, tie-off points, damaged components, proper access, and the use
of fall protection equipment.

Maintenance and Storage
Maintain scaffolds in good repair. Only replacement components from the original manufacturer should be used.
Intermixing scaffold components from different manufacturers should be avoided. Fabricated scaffolds should be repaired
according to the manufacturer’s specifications and guidance. Job-built scaffolds should not be repaired without the supervision of a competent person.
Store all scaffolding parts in an organized manner in a dry and protected environment. Examine all parts and clean,
repair or dispose of them as necessary.

5


3
Illustrations of Selected Types of Scaffolds
Illustrations in this part offer the reader a general pictorial representation of selected types of scaffolds which are
addressed by standards enforced under the Occupational Safety and Health Act of North Carolina (OSHANC standards).
The reader must not rely upon the illustrations to determine safety requirements or safe use of the equipment for any particular installation situation. Rather, the reader should refer to the appropriate OSHANC standard and related tables for
specific information. The illustrations reference the OSHANC standards (29 CFR 1926 applies to the construction industry and 29 CFR 1910 applies to general industry).
Illustrations in this part were provided by the Scaffolding Industry Association. The illustrations are not intended by
the N.C. Department of Labor or the Scaffolding Industry Association to endorse any specific product, design or installation.
Figure 1
Scaffolding Work Surfaces [29 CFR 1926.451(a); 29 CFR 1910.28(a)]

LAMINATED
VENEER
LUMBER
(LVL)

SOLID
SAWN
LUMBER
SCAFFOLD PLANKS

FABRICATED
SCAFFOLD
PLANK

FABRICATED
SCAFFOLD
DECK

STAGE
PLATFORM

DECORATOR
PLANK

WOOD
SCAFFOLD
PLANK

METAL
SCAFFOLD
PLANK

MODULAR
STAGE
PLATFORM

6


Figure 2
Wood Pole Scaffold [29 CFR 1926.452(a); 29 CFR 1910.28(b)]
POLE

PLANKED LEVELS
GUARDRAIL SYSTEM
ACCESS LADDER

BEARER

DIAGONAL BRACING
RUNNER

Figure 3
Tube and Coupler Scaffold [29 CFR 1926.452(b); 29 CFR 1910.28(c)]
PLANKING
GUARDRAIL SYSTEM
WITH TOEBOARDS

RUNNER
BEARER
POST

RIGID
CLAMP

SILL
DIAGONAL BRACE
CROSSBRACING

BASE PLATE

SWIVEL
CLAMP

7

TYPICAL
JOINT
CONNECTION


Figure 4
Fabricated Frame Scaffold (Tubular Welded Frame Scaffold) [29 CFR 1926.452(c); 29 CFR 1910.28(d)
and Scaffold Access (Ladder or Equivalent) [29 CFR 1926.451(e); 29 CFR 1910.28(a)(12)]

HANDRAIL SYSTEM

GUARDRAIL
CROSSBRACE

FRAME or
PANEL
STEP UNIT

INTERNAL STAIR UNIT
ACCESS
GATE
INTERMEDIATE
LEVEL

TOEBOARDS
FRAME
or
PANEL
ACCESS
LADDER

BRACKET
ATTACHMENT
COUPLER

EXTERNAL LADDERS
ATTACHABLE

BUILT-IN

8


Figure 5
Manually Propelled Mobile Scaffold (Fabricated Tubular Frame) [29 CFR 1926.452(w); 29 CFR 1910.29]
WORK
PLATFORM

GUARDRAIL SYSTEM

END
FRAME

ACCESS
GATE

TOEBOARD

LOCKING
PINS

COUPLER

ACCESS
LADDER

CROSSBRACING

HORIZONTAL
DIAGONAL
BRACE

LOCKING
CASTERS
CASTER FASTENING PINS

9


Figure 6
Examples of Vehicle-Mounted Elevating and Rotating Aerial Devices (covered by ANSI A92.2) [29 CFR 1926.453]

VEHICLE-MOUNTED AERIAL PLATFORM WITH
TELESCOPING AND ROTATING BOOM

VEHICLE-MOUNTED AERIAL PLATFORM
(SCISSOR TYPE)

10


Figure 7
Outrigger Scaffold [29 CFR 1926.452(i); 29 CFR 1910.28(e)]

THIS END
RIGIDLY SECURED

OUTRIGGER BEAM BLOCKED
FOR LATERAL SUPPORT

11


Figure 8
Mason’s Adjustable Multiple-point Suspension Scaffold (With Winding Drum Hoists) [29 CFR 1926.452(q); 29 CFR 1910.28(f)]

ALTERNATE BOLT & SPECIAL
ANCHOR IMBEDDED IN CONCRETE
AT TIME OF POUR
ANCHORAGE SYSTEM

TYPICAL SUPPORT FOR
STRUCTURAL STEEL

OVERHEAD PROTECTION

GUARDRAIL
SYSTEM
WITH SCREEN

12

BUILDING
STEEL


Figure 9
(Swinging Scaffold) Two-point Suspension [29 CFR 1926.452(p); 29 CFR 1910.28(g)]
COUNTERWEIGHTS
TIEBACK
COUNTERWEIGHTS
TIEBACK
OUTRIGGER
BEAM

SUSPENSION
WIRE ROPES

ROLLING
OUTRIGGER BEAM

TIEBACKS

PARAPET CLAMP

SECOND
WIRE ROPE
WOOD
BLOCKING

ROOF HOOK

SUSPENSION
WIRE ROPE

POWERED TRACTION HOIST

SUSPENSION
WIRE ROPES

PLATFORM
GUARDRAIL SYSTEM WITH SCREEN & TOEBOARDS
GUARDRAIL SYSTEM WITH TOEBOARDS

SUSPENSION
WIRE ROPE
POWER WINDING DRUM HOIST

MODULAR PLATFORM

GUARDRAIL SYSTEM WITH
TOEBOARDS

MANUAL WINDING DRUM HOIST
PLATFORM

13


Figure 10
Multiple-point Suspension Scaffold [29 CFR 1926.452(q)]

INDEPENDENT LINE

HOIST
LINE

GUARDRAIL
SYSTEM

STAGE

HOIST

14


Figure 11
Multi-level Suspension Scaffold With Powered Hoists [29 CFR 1926.452(v)]

SECOND WIRE ROPE
LANYARD ATTACHED TO TROLLY LINE
SUSPENSION
WIRE ROPE

HOISTING
MACHINE

PLATFORM
UNITS

GUARDRAIL
SYSTEM
GUARDRAIL
SYSTEM

15


Figure 12
Stone Setters’ Adjustable Multiple-point Suspension Scaffold (With Manual Winding Drum Hoists)
[29 CFR 1926.452(q); 29 CFR 1910.28(h)]

HOIST LINE

OUTSIDE WIRE ROPE
TOPRAIL

GUARDRAIL
BRACKETS

INSIDE WIRE
ROPE
OPERATING
HANDLE

MIDRAIL
TOEBOARD

GUIDE
CLAMP

ROLLER BUNTER
PLATFORM

PUTLOG
PUTLOG HINGE BOLT

END GUARDRAIL
SYSTEM

TOPRAIL

INTERMEDIATE
GUARDRAIL
SUPPORT

GUARDRAIL
SUPPORT

CORNER BRACE
BOLT
WIRE ROPE
GUIDE WHEEL

END BRACKET
END GUARDRAIL
SYSTEM

MIDRAIL
TOEBOARD
PLATFORM SIDERAIL

Figure 13
Single-point Adjustable Suspension Scaffolds (Work Cages) [29 CFR 1926.452(o); 29 CFR 1910.28(i)]

POWER TRACTION HOIST
WORK CAGE

POWER TRACTION HOIST
WORK CAGE WITH EXTENSIONS

16

SINGLE POINT SUSPENSION
SCAFFOLD WINDING DRUM HOIST


Figure 14
Single-point Adjustable Suspension Scaffold Boatswain’s Chairs [29 CFR 1926.452(o); 29 CFR 1910.28(j)]

BOATSWAIN CHAIR
MANUAL

BOATSWAIN CHAIR
POWERED

Figure 15
Form Scaffold Carpenter’s Bracket Scaffold (Metal) [29 CFR 1926.452(g); 29 CFR 1910.28(k)]
WALL STUD

GUARDRAIL
POST
LOCATION

THRU BOLT

17


Figure 16

Figure 17

Bricklayer’s Square Scaffold [29 CFR 1926.452(e)]

Horse Scaffold [29 CFR 1926.452(f); 29 CFR 1910.28(m)]

BEARERS

LIGHT DUTY 8' MAX
MEDIUM DUTY 5' MAX

LEGS

CORNER
BRACES

Figure 18
Needle Beam Scaffold (Structural Member Above) [29 CFR 1926.452(u); 29 CFR 1910.28(n)]

ROPES

NEEDLE BEAM

PLATFORM

18


Figure 19
Interior Hung Scaffold [29 CFR 1926.452(t); 29 CFR 1910.28(p)]

BUILDING
STRUCTURAL MEMBER

SUPPORTING ROPE
(ALTERNATE TUBE & COUPLER)

PLANK

BEARER

Figure 20
Catenary Scaffold [29 CFR 1910.28(g); 29 CFR 1926.452(r)]
STRUCTURE ABOVE

PLATFORM

VERTICAL PICKUPS

ANCHORED

ANCHORED

WIRE ROPE
HOOK STOPS

19


Figure 21
Ladder Jack Scaffold [29 CFR 1926.452(k); 29 CFR 1910.28(q)]

PLANK
OVERHANG

HEAVY-DUTY
LADDER

LENGTH OF FABRICATED
PLANK VARIES
LADDER JACK
(SECURE PLANK TO BOTH
LADDER JACKS)

HEIGHT

SECURE TOP AND
BOTTOM OF BOTH
LADDERS

UPPERMOST USABLE
RUNG—SECOND
HIGHEST

JACK INSTALLED ON SIDE
OF LADDER AWAY FROM
SURFACE

JACK INSTALLED ON SIDE
OF LADDER TOWARD
SURFACE

Figure 22
Window Jack Scaffold [29 CFR 1926.452(l); 29 CFR 1910.28(r)]

BUILDING
STRUCTURE

ANCHOR

WINDOW OPENING

20


Figure 23
Float or Ship Scaffold [29 CFR 1926.452(s); 29 CFR 1910.28(u)]
STRUCTURAL MEMBER

SUPPORT ROPE
DECK WITH BRACING
EDGE PROTECTION

Figure 24
Pump Jack Scaffold [29 CFR 1926.452(j)]
STRUCTURE

POLE

WORKBENCH
(GUARDRAIL)

POLE

BRACE

MIDRAIL

END
GUARDRAIL
SYSTEM

TOEBOARD

WORK PLATFORM

PUMP JACK
BRACKET

BRACE
MUD SILLS

21


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