|
Back
to Contents
PART
1926 -- Safety and Health Regulations for Construction
1926.451 -
General requirements
This
section does not apply to aerial lifts, the criteria for which are set
out exclusively in 1926.453.
(a)
"Capacity"
(a)(1)
Except
as provided in paragraphs (a)(2), (a)(3), (a)(4), (a)(5) and (g) of this
section, each scaffold and scaffold component shall be capable of supporting,
without failure, its own weight and at least 4 times the maximum intended
load applied or transmitted to it.
(a)(2)
Direct
connections to roofs and floors, and counterweights used to balance adjustable
suspension scaffolds, shall be capable of resisting at least 4 times the
tipping moment imposed by the scaffold operating at the rated load of
the hoist, or 1.5 (minimum) times the tipping moment imposed by the scaffold
operating at the stall load of the hoist, whichever is greater.
(a)(3)
Each
suspension rope, including connecting hardware, used on non-adjustable
suspension scaffolds shall be capable of supporting, without failure,
at least 6 times the maximum intended load applied or transmitted to that
rope.
..1926.451(a)(4)
(a)(4)
Each
suspension rope, including connecting hardware, used on adjustable suspension
scaffolds shall be capable of supporting, without failure, at least 6
times the maximum intended load applied or transmitted to that rope with
the scaffold operating at either the rated load of the hoist, or 2 (minimum)
times the stall load of the hoist, whichever is greater.
(a)(5)
The
stall load of any scaffold hoist shall not exceed 3 times its rated load.
(a)(6)
Scaffolds
shall be designed by a qualified person and shall be constructed and loaded
in accordance with that design. Non-mandatory Appendix A to this subpart
contains examples of criteria that will enable an employer to comply with
paragraph (a) of this section.
(b)
"Scaffold
platform construction."
(b)(1)
Each
platform on all working levels of scaffolds shall be fully planked or
decked between the front uprights and the guardrail supports as follows:
(b)(1)(i)
Each
platform unit (e.g., scaffold plank, fabricated plank, fabricated deck,
or fabricated platform) shall be installed so that the space between adjacent
units and the space between the platform and the uprights is no more than
1 inch (2.5 cm) wide, except where the employer can demonstrate that a
wider space is necessary (for example, to fit around uprights when side
brackets are used to extend the width of the platform).
..1926.451(b)(1)(ii)
(b)(1)(ii)
Where
the employer makes the demonstration provided for in paragraph (b)(1)(i)
of this section, the platform shall be planked or decked as fully as possible
and the remaining open space between the platform and the uprights shall
not exceed 9 1/2 inches (24.1 cm).
Exception
to paragraph (b)(1): The requirement in paragraph (b)(1) to provide full
planking or decking does not apply to platforms used solely as walkways
or solely by employees performing scaffold erection or dismantling. In
these situations, only the planking that the employer establishes is necessary
to provide safe working conditions is required.
(b)(2)
Except
as provided in paragraphs (b)(2)(i) and (b)(2)(ii) of this section, each
scaffold platform and walkway shall be at least 18 inches (46 cm) wide.
(b)(2)(i)
Each
ladder jack scaffold, top plate bracket scaffold, roof bracket scaffold,
and pump jack scaffold shall be at least 12 inches (30 cm) wide. There
is no minimum width requirement for boatswains' chairs.
Note
to paragraph (b)(2)(i): Pursuant to an administrative stay effective November
29, 1996 and published in the Federal Register on November 25, 1996, the
requirement in paragraph (b)(2)(i) that roof bracket scaffolds be at least
12 inches wide is stayed until November 25, 1997 or until rulemaking reguarding
the minimum width of roof bracket scaffolds has been completed, whichever
is later.
(b)(2)(ii)
Where
scaffolds must be used in areas that the employer can demonstrate are
so narrow that platforms and walkways cannot be at least 18 inches (46
cm) wide, such platforms and walkways shall be as wide as feasible, and
employees on those platforms and walkways shall be protected from fall
hazards by the use of guardrails and/or personal fall arrest systems.
(b)(3)
Except
as provided in paragraphs (b)(3)(i) and (ii) of this section, the front
edge of all platforms shall not be more than 14 inches (36 cm) from the
face of the work, unless guardrail systems are erected along the front
edge and/or personal fall arrest systems are used in accordance with paragraph
(g) of this section to protect employees from falling.
..1926.451(b)(3)(i)
(b)(3)(i)
The
maximum distance from the face for outrigger scaffolds shall be 3 inches
(8 cm);
(b)(3)(ii)
The
maximum distance from the face for plastering and lathing operations shall
be 18 inches (46 cm).
(b)(4)
Each
end of a platform, unless cleated or otherwise restrained by hooks or
equivalent means, shall extend over the centerline of its support at least
6 inches (15 cm).
(b)(5)
(b)(5)(i)
Each
end of a platform 10 feet or less in length shall not extend over its
support more than 12 inches (30 cm) unless the platform is designed and
installed so that the cantilevered portion of the platform is able to
support employees and/or materials without tipping, or has guardrails
which block employee access to the cantilevered end.
(b)(5)(ii)
Each
platform greater than 10 feet in length shall not extend over its support
more than 18 inches (46 cm), unless it is designed and installed so that
the cantilevered portion of the platform is able to support employees
without tipping, or has guardrails which block employee access to the
cantilevered end.
..1926.451(b)(6)
(b)(6)
On
scaffolds where scaffold planks are abutted to create a long platform,
each abutted end shall rest on a separate support surface. This provision
does not preclude the use of common support members, such as "T"
sections, to support abutting planks, or hook on platforms designed to
rest on common supports.
(b)(7)
On
scaffolds where platforms are overlapped to create a long platform, the
overlap shall occur only over supports, and shall not be less than 12
inches (30 cm) unless the platforms are nailed together or otherwise restrained
to prevent movement.
(b)(8)
At
all points of a scaffold where the platform changes direction, such as
turning a corner, any platform that rests on a bearer at an angle other
than a right angle shall be laid first, and platforms which rest at right
angles over the same bearer shall be laid second, on top of the first
platform.
(b)(9)
Wood
platforms shall not be covered with opaque finishes, except that platform
edges may be covered or marked for identification. Platforms may be coated
periodically with wood preservatives, fire-retardant finishes, and slip-resistant
finishes; however, the coating may not obscure the top or bottom wood
surfaces.
(b)(10)
Scaffold
components manufactured by different manufacturers shall not be intermixed
unless the components fit together without force and the scaffold's structural
integrity is maintained by the user. Scaffold components manufactured
by different manufacturers shall not be modified in order to intermix
them unless a competent person determines the resulting scaffold is structurally
sound.
..1926.451(b)(11)
(b)(11)
Scaffold
components made of dissimilar metals shall not be used together unless
a competent person has determined that galvanic action will not reduce
the strength of any component to a level below that required by paragraph
(a)(1) of this section.
(c)
"Criteria
for supported scaffolds."
(c)(1)
Supported
scaffolds with a height to base width (including outrigger supports, if
used) ratio of more than four to one (4:1) shall be restrained from tipping
by guying, tying, bracing, or equivalent means, as follows:
(c)(1)(i)
Guys,
ties, and braces shall be installed at locations where horizontal members
support both inner and outer legs.
(c)(1)(ii)
Guys,
ties, and braces shall be installed according to the scaffold manufacturer's
recommendations or at the closest horizontal member to the 4:1 height
and be repeated vertically at locations of horizontal members every 20
feet (6.1 m) or less thereafter for scaffolds 3 feet (0.91 m) wide or
less, and every 26 feet (7.9 m) or less thereafter for scaffolds greater
than 3 feet (0.91 m) wide. The top guy, tie or brace of completed scaffolds
shall be placed no further than the 4:1 height from the top. Such guys,
ties and braces shall be installed at each end of the scaffold and at
horizontal intervals not to exceed 30 feet (9.1 m) (measured from one
end [not both] towards the other).
(c)(1)(iii)
Ties,
guys, braces, or outriggers shall be used to prevent the tipping of supported
scaffolds in all circumstances where an eccentric load, such as a cantilevered
work platform, is applied or is transmitted to the scaffold.
..1926.451(c)(2)
(c)(2)
Supported
scaffold poles, legs, posts, frames, and uprights shall bear on base plates
and mud sills or other adequate firm foundation.
(c)(2)(i)
Footings
shall be level, sound, rigid, and capable of supporting the loaded scaffold
without settling or displacement.
(c)(2)(ii)
Unstable
objects shall not be used to support scaffolds or platform units.
(c)(2)(iii)
Unstable
objects shall not be used as working platforms.
(c)(2)(iv)
Front-end
loaders and similar pieces of equipment shall not be used to support scaffold
platforms unless they have been specifically designed by the manufacturer
for such use.
(c)(2)(v)
Fork-lifts
shall not be used to support scaffold platforms unless the entire platform
is attached to the fork and the fork-lift is not moved horizontally while
the platform is occupied.
(c)(3)
Supported
scaffold poles, legs, posts, frames, and uprights shall be plumb and braced
to prevent swaying and displacement.
..1926.451(d)
(d)
"Criteria
for suspension scaffolds."
(d)(1)
All
suspension scaffold support devices, such as outrigger beams, cornice
hooks, parapet clamps, and similar devices, shall rest on surfaces capable
of supporting at least 4 times the load imposed on them by the scaffold
operating at the rated load of the hoist (or at least 1.5 times the load
imposed on them by the scaffold at the stall capacity of the hoist, whichever
is greater).
(d)(2)
Suspension
scaffold outrigger beams, when used, shall be made of structural metal
or equivalent strength material, and shall be restrained to prevent movement.
(d)(3)
The
inboard ends of suspension scaffold outrigger beams shall be stabilized
by bolts or other direct connections to the floor or roof deck, or they
shall have their inboard ends stabilized by counterweights, except masons'
multi-point adjustable suspension scaffold outrigger beams shall not be
stabilized by counterweights.
(d)(3)(i)
Before
the scaffold is used, direct connections shall be evaluated by a competent
person who shall confirm, based on the evaluation, that the supporting
surfaces are capable of supporting the loads to be imposed. In addition,
masons' multi-point adjustable suspension scaffold connections shall be
designed by an engineer experienced in such scaffold design.
(d)(3)(ii)
Counterweights
shall be made of non-flowable material. Sand, gravel and similar materials
that can be easily dislocated shall not be used as counterweights.
..1926.451(d)(3)(iii)
(d)(3)(iii)
Only
those items specifically designed as counterweights shall be used to counterweight
scaffold systems. Construction materials such as, but not limited to,
masonry units and rolls of roofing felt, shall not be used as counterweights.
(d)(3)(iv)
Counterweights
shall be secured by mechanical means to the outrigger beams to prevent
accidental displacement.
(d)(3)(v)
Counterweights
shall not be removed from an outrigger beam until the scaffold is disassembled.
(d)(3)(vi)
Outrigger
beams which are not stabilized by bolts or other direct connections to
the floor or roof deck shall be secured by tiebacks.
(d)(3)(vii)
Tiebacks
shall be equivalent in strength to the suspension ropes.
(d)(3)(viii)
Outrigger
beams shall be placed perpendicular to its bearing support (usually the
face of the building or structure). However, where the employer can demonstrate
that it is not possible to place an outrigger beam perpendicular to the
face of the building or structure because of obstructions that cannot
be moved, the outrigger beam may be placed at some other angle, provided
opposing angle tiebacks are used.
..1926.451(d)(3)(ix)
(d)(3)(ix)
Tiebacks
shall be secured to a structurally sound anchorage on the building or
structure. Sound anchorages include structural members, but do not include
standpipes, vents, other piping systems, or electrical conduit.
(d)(3)(x)
Tiebacks
shall be installed perpendicular to the face of the building or structure,
or opposing angle tiebacks shall be installed. Single tiebacks installed
at an angle are prohibited.
(d)(4)
Suspension
scaffold outrigger beams shall be:
(d)(4)(i)
Provided
with stop bolts or shackles at both ends;
(d)(4)(ii)
Securely
fastened together with the flanges turned out when channel iron beams
are used in place of I-beams;
(d)(4)(iii)
Installed
with all bearing supports perpendicular to the beam center line;
(d)(4)(iv)
Set
and maintained with the web in a vertical position; and
(d)(4)(v)
When
an outrigger beam is used, the shackle or clevis with which the rope is
attached to the outrigger beam shall be placed directly over the center
line of the stirrup.
(d)(5)
Suspension
scaffold support devices such as cornice hooks, roof hooks, roof irons,
parapet clamps, or similar devices shall be:
..1926.451(d)(5)(i)
(d)(5)(i)
Made
of steel, wrought iron, or materials of equivalent strength;
(d)(5)(ii)
Supported
by bearing blocks; and
(d)(5)(iii)
Secured
against movement by tiebacks installed at right angles to the face of
the building or structure, or opposing angle tiebacks shall be installed
and secured to a structurally sound point of anchorage on the building
or structure. Sound points of anchorage include structural members, but
do not include standpipes, vents, other piping systems, or electrical
conduit.
(d)(5)(iv)
Tiebacks
shall be equivalent in strength to the hoisting rope.
(d)(6)
When
winding drum hoists are used on a suspension scaffold, they shall contain
not less than four wraps of the suspension rope at the lowest point of
scaffold travel. When other types of hoists are used, the suspension ropes
shall be long enough to allow the scaffold to be lowered to the level
below without the rope end passing through the hoist, or the rope end
shall be configured or provided with means to prevent the end from passing
through the hoist.
(d)(7)
The
use of repaired wire rope as suspension rope is prohibited.
..1926.451(d)(8)
(d)(8)
Wire
suspension ropes shall not be joined together except through the use of
eye splice thimbles connected with shackles or coverplates and bolts.
(d)(9)
The
load end of wire suspension ropes shall be equipped with proper size thimbles
and secured by eyesplicing or equivalent means.
(d)(10)
Ropes
shall be inspected for defects by a competent person prior to each workshift
and after every occurrence which could affect a rope's integrity. Ropes
shall be replaced if any of the following conditions exist:
(d)(10)(i)
Any
physical damage which impairs the function and strength of the rope.
(d)(10)(ii)
Kinks
that might impair the tracking or wrapping of rope around the drum(s)
or sheave(s).
(d)(10)(iii)
Six
randomly distributed broken wires in one rope lay or three broken wires
in one strand in one rope lay.
(d)(10)(iv)
Abrasion,
corrosion, scrubbing, flattening or peening causing loss of more than
one-third of the original diameter of the outside wires.
(d)(10)(v)
Heat
damage caused by a torch or any damage caused by contact with electrical
wires.
..1926.451(d)(10)(vi)
(d)(10)(vi)
Evidence
that the secondary brake has been activated during an overspeed condition
and has engaged the suspension rope.
(d)(11)
Swaged
attachments or spliced eyes on wire suspension ropes shall not be used
unless they are made by the wire rope manufacturer or a qualified person.
(d)(12)
When
wire rope clips are used on suspension scaffolds:
(d)(12)(i)
There
shall be a minimum of 3 wire rope clips installed, with the clips a minimum
of 6 rope diameters apart;
(d)(12)(ii)
Clips
shall be installed according to the manufacturer's recommendations;
(d)(12)(iii)
Clips
shall be retightened to the manufacturer's recommendations after the initial
loading;
(d)(12)(iv)
Clips
shall be inspected and retightened to the manufacturer's recommendations
at the start of each workshift thereafter;
(d)(12)(v)
U-bolt
clips shall not be used at the point of suspension for any scaffold hoist;
..1926.451(d)(12)(vi)
(d)(12)(vi)
When
U-bolt clips are used, the U-bolt shall be placed over the dead end of
the rope, and the saddle shall be placed over the live end of the rope.
(d)(13)
Suspension
scaffold power-operated hoists and manual hoists shall be tested by a
qualified testing laboratory.
(d)(14)
Gasoline-powered
equipment and hoists shall not be used on suspension scaffolds.
(d)(15)
Gears
and brakes of power-operated hoists used on suspension scaffolds shall
be enclosed.
(d)(16)
In
addition to the normal operating brake, suspension scaffold power-operated
hoists and manually operated hoists shall have a braking device or locking
pawl which engages automatically when a hoist makes either of the following
uncontrolled movements: an instantaneous change in momentum or an accelerated
overspeed.
(d)(17)
Manually
operated hoists shall require a positive crank force to descend.
(d)(18)
Two-point
and multi-point suspension scaffolds shall be tied or otherwise secured
to prevent them from swaying, as determined to be necessary based on an
evaluation by a competent person. Window cleaners' anchors shall not be
used for this purpose.
..1926.451(d)(19)
(d)(19)
Devices
whose sole function is to provide emergency escape and rescue shall not
be used as working platforms. This provision does not preclude the use
of systems which are designed to function both as suspension scaffolds
and emergency systems.
(e)
"Access."
This paragraph applies to scaffold access for all employees. Access requirements
for employees erecting or dismantling supported scaffolds are specifically
addressed in paragraph (e)(9) of this section.
(e)(1)
When
scaffold platforms are more than 2 feet (0.6 m) above or below a point
of access, portable ladders, hook-on ladders, attachable ladders, stair
towers (scaffold stairways/towers), stairway-type ladders (such as ladder
stands), ramps, walkways, integral prefabricated scaffold access, or direct
access from another scaffold, structure, personnel hoist, or similar surface
shall be used. Crossbraces shall not be used as a means of access.
(e)(2)
Portable,
hook-on, and attachable ladders (Additional requirements for the proper
construction and use of portable ladders are contained in subpart X of
this part -- Stairways and Ladders):
(e)(2)(i)
Portable,
hook-on, and attachable ladders shall be positioned so as not to tip the
scaffold;
(e)(2)(ii)
Hook-on
and attachable ladders shall be positioned so that their bottom rung is
not more than 24 inches (61 cm) above the scaffold supporting level;
..1926.451(e)(2)(iii)
(e)(2)(iii)
When
hook-on and attachable ladders are used on a supported scaffold more than
35 feet (10.7 m) high, they shall have rest platforms at 35-foot (10.7
m) maximum vertical intervals.
(e)(2)(iv)
Hook-on
and attachable ladders shall be specifically designed for use with the
type of scaffold used;
(e)(2)(v)
Hook-on
and attachable ladders shall have a minimum rung length of 11 1/2 inches
(29 cm); and
(e)(2)(vi)
Hook-on
and attachable ladders shall have uniformly spaced rungs with a maximum
spacing between rungs of 16 3/4 inches.
(e)(3)
Stairway-type
ladders shall:
(e)(3)(i)
Be
positioned such that their bottom step is not more than 24 inches (61
cm) above the scaffold supporting level;
(e)(3)(ii)
Be
provided with rest platforms at 12 foot (3.7 m) maximum vertical intervals;
(e)(3)(iii)
Have
a minimum step width of 16 inches (41 cm), except that mobile scaffold
stairway-type ladders shall have a minimum step width of 11 1/2 inches
(30 cm); and
(e)(3)(iv)
Have
slip-resistant treads on all steps and landings.
..1926.451(e)(4)
(e)(4)
Stairtowers
(scaffold stairway/towers) shall be positioned such that their bottom
step is not more than 24 inches (61 cm.) above the scaffold supporting
level.
(e)(4)(i)
A
stairrail consisting of a toprail and a midrail shall be provided on each
side of each scaffold stairway.
(e)(4)(ii)
The
toprail of each stairrail system shall also be capable of serving as a
handrail, unless a separate handrail is provided.
(e)(4)(iii)
Handrails,
and toprails that serve as handrails, shall provide an adequate handhold
for employees grasping them to avoid falling.
(e)(4)(iv)
Stairrail
systems and handrails shall be surfaced to prevent injury to employees
from punctures or lacerations, and to prevent snagging of clothing.
(e)(4)(v)
The
ends of stairrail systems and handrails shall be constructed so that they
do not constitute a projection hazard.
(e)(4)(vi)
Handrails,
and toprails that are used as handrails, shall be at least 3 inches (7.6
cm) from other objects.
..1926.451(e)(4)(vii)
(e)(4)(vii)
Stairrails
shall be not less than 28 inches (71 cm) nor more than 37 inches (94 cm)
from the upper surface of the stairrail to the surface of the tread, in
line with the face of the riser at the forward edge of the tread.
(e)(4)(viii)
A
landing platform at least 18 inches (45.7 cm) wide by at least 18 inches
(45.7 cm) long shall be provided at each level.
(e)(4)(ix)
Each
scaffold stairway shall be at least 18 inches (45.7 cm) wide between stairrails.
(e)(4)(x)
Treads
and landings shall have slip-resistant surfaces.
(e)(4)(xi)
Stairways
shall be installed between 40 degrees and 60 degrees from the horizontal.
(e)(4)(xii)
Guardrails
meeting the requirements of paragraph (g)(4) of this section shall be
provided on the open sides and ends of each landing.
(e)(4)(xiii)
Riser
height shall be uniform, within 1/4 inch, (0.6 cm) for each flight of
stairs. Greater variations in riser height are allowed for the top and
bottom steps of the entire system, not for each flight of stairs.
(e)(4)(xiv)
Tread
depth shall be uniform, within 1/4 inch, for each flight of stairs.
..1926.451(e)(5)
(e)(5)
Ramps
and walkways.
(e)(5)(i)
Ramps
and walkways 6 feet (1.8 m) or more above lower levels shall have guardrail
systems which comply with subpart M of this part -- Fall Protection;
(e)(5)(ii)
No
ramp or walkway shall be inclined more than a slope of one (1) vertical
to three (3) horizontal (20 degrees above the horizontal).
(e)(5)(iii)
If
the slope of a ramp or a walkway is steeper than one (1) vertical in eight
(8) horizontal, the ramp or walkway shall have cleats not more than fourteen
(14) inches (35 cm) apart which are securely fastened to the planks to
provide footing.
(e)(6)
Integral
prefabricated scaffold access frames shall:
(e)(6)(i)
Be
specifically designed and constructed for use as ladder rungs;
(e)(6)(ii)
Have
a rung length of at least 8 inches (20 cm);
(e)(6)(iii)
Not
be used as work platforms when rungs are less than 11 1/2 inches in length,
unless each affected employee uses fall protection, or a positioning device,
which complies with 1926.502;
(e)(6)(iv)
Be
uniformly spaced within each frame section;
..1926.451(e)(6)(v)
(e)(6)(v)
Be
provided with rest platforms at 35-foot (10.7 m) maximum vertical intervals
on all supported scaffolds more than 35 feet (10.7 m) high; and
(e)(6)(vi)
Have
a maximum spacing between rungs of 16 3/4 inches (43 cm). Non-uniform
rung spacing caused by joining end frames together is allowed, provided
the resulting spacing does not exceed 16 3/4 inches (43 cm).
(e)(7)
Steps
and rungs of ladder and stairway type access shall line up vertically
with each other between rest platforms.
(e)(8)
Direct
access to or from another surface shall be used only when the scaffold
is not more than 14 inches (36 cm) horizontally and not more than 24 inches
(61 cm) vertically from the other surface.
(e)(9)
Effective
September 2, 1997, access for employees erecting or dismantling supported
scaffolds shall be in accordance with the following:
..1926.451(e)(9)(i)
(e)(9)(i)
The
employer shall provide safe means of access for each employee erecting
or dismantling a scaffold where the provision of safe access is feasible
and does not create a greater hazard. The employer shall have a competent
person determine whether it is feasible or would pose a greater hazard
to provide, and have employees use a safe means of access. This determination
shall be based on site conditions and the type of scaffold being erected
or dismantled.
(e)(9)(ii)
Hook-on
or attachable ladders shall be installed as soon as scaffold erection
has progressed to a point that permits safe installation and use.
(e)(9)(iii)
When
erecting or dismantling tubular welded frame scaffolds, (end) frames,
with horizontal members that are parallel, level and are not more than
22 inches apart vertically may be used as climbing devices for access,
provided they are erected in a manner that creates a usable ladder and
provides good hand hold and foot space.
(e)(9)(iv)
Cross
braces on tubular welded frame scaffolds shall not be used as a means
of access or egress.
(f)
"Use."
(f)(1)
Scaffolds
and scaffold components shall not be loaded in excess of their maximum
intended loads or rated capacities, whichever is less.
(f)(2)
The
use of shore or lean-to scaffolds is prohibited.
..1926.451(f)(3)
(f)(3)
Scaffolds
and scaffold components shall be inspected for visible defects by a competent
person before each work shift, and after any occurrence which could affect
a scaffold's structural integrity.
(f)(4)
Any
part of a scaffold damaged or weakened such that its strength is less
than that required by paragraph (a) of this section shall be immediately
repaired or replaced, braced to meet those provisions, or removed from
service until repaired.
(f)(5)
Scaffolds
shall not be moved horizontally while employees are on them, unless they
have been designed by a registered professional engineer specifically
for such movement or, for mobile scaffolds, where the provisions of 1926.452(w)
are followed.
(f)(6)
The
clearance between scaffolds and power lines shall be as follows: Scaffolds
shall not be erected, used, dismantled, altered, or moved such that they
or any conductive material handled on them might come closer to exposed
and energized power lines than as follows:
*Insulated Lines
_____________________________________________________________________
| |
Voltage | Minimum distance | Alternatives
____________________|________________________|_______________________
| |
Less than 300 volts.| 3 feet (0.9 m) |
300 volts to 50 kv.| 10 feet (3.1 m) |
More than 50 kv.....| 10 feet (3.1 m) plus | 2 times the length
| 0.4 inches (1.0 cm) | of the line
| for each 1 kv over | insulator, but never
| 50 kv. | less than 10
| | feet (3.1 m).
____________________|________________________|_______________________
*Uninsulated lines
_____________________________________________________________________
| |
Voltage | Minimum distance | Alternatives
____________________|________________________|_______________________
| |
Less than 50 kv.....| 10 feet (3.1 m). |
More than 50 kv.....| 10 feet (3.1 m) plus | 2 times the length of
| 0.4 inches (1.0 cm) | the line insulator,
| for each 1 kv over | but never less than
| 50 kv. | 10 feet (3.1 m).
____________________|________________________|_______________________
Exception
to paragraph (f)(6): Scaffolds and materials may be closer to power lines
than specified above where such clearance is necessary for performance
of work, and only after the utility company, or electrical system operator,
has been notified of the need to work closer and the utility company,
or electrical system operator, has deenergized the lines, relocated the
lines, or installed protective coverings to prevent accidental contact
with the lines.
(f)(7)
Scaffolds
shall be erected, moved, dismantled, or altered only under the supervision
and direction of a competent person qualified in scaffold erection, moving,
dismantling or alteration. Such activities shall be performed only by
experienced and trained employees selected for such work by the competent
person.
..1926.451(f)(8)
(f)(8)
Employees
shall be prohibited from working on scaffolds covered with snow, ice,
or other slippery material except as necessary for removal of such materials.
(f)(9)
Where
swinging loads are being hoisted onto or near scaffolds such that the
loads might contact the scaffold, tag lines or equivalent measures to
control the loads shall be used.
(f)(10)
Suspension
ropes supporting adjustable suspension scaffolds shall be of a diameter
large enough to provide sufficient surface area for the functioning of
brake and hoist mechanisms.
(f)(11)
Suspension
ropes shall be shielded from heat-producing processes. When acids or other
corrosive substances are used on a scaffold, the ropes shall be shielded,
treated to protect against the corrosive substances, or shall be of a
material that will not be damaged by the substance being used.
(f)(12)
Work
on or from scaffolds is prohibited during storms or high winds unless
a competent person has determined that it is safe for employees to be
on the scaffold and those employees are protected by a personal fall arrest
system or wind screens. Wind screens shall not be used unless the scaffold
is secured against the anticipated wind forces imposed.
(f)(13)
Debris
shall not be allowed to accumulate on platforms.
..1926.451(f)(14)
(f)(14)
Makeshift
devices, such as but not limited to boxes and barrels, shall not be used
on top of scaffold platforms to increase the working level height of employees.
(f)(15)
Ladders
shall not be used on scaffolds to increase the working level height of
employees, except on large area scaffolds where employers have satisfied
the following criteria:
(f)(15)(i)
When
the ladder is placed against a structure which is not a part of the scaffold,
the scaffold shall be secured against the sideways thrust exerted by the
ladder;
(f)(15)(ii)
The
platform units shall be secured to the scaffold to prevent their movement;
(f)(15)(iii)
The
ladder legs shall be on the same platform or other means shall be provided
to stabilize the ladder against unequal platform deflection, and
(f)(15)(iv)
The
ladder legs shall be secured to prevent them from slipping or being pushed
off the platform.
(f)(16)
Platforms
shall not deflect more than 1/60 of the span when loaded.
(f)(17)
To
reduce the possibility of welding current arcing through the suspension
wire rope when performing welding from suspended scaffolds, the following
precautions shall be taken, as applicable:
..1926.451(f)(17)(i)
(f)(17)(i)
An
insulated thimble shall be used to attach each suspension wire rope to
its hanging support (such as cornice hook or outrigger). Excess suspension
wire rope and any additional independent lines from grounding shall be
insulated;
(f)(17)(ii)
The
suspension wire rope shall be covered with insulating material extending
at least 4 feet (1.2 m) above the hoist. If there is a tail line below
the hoist, it shall be insulated to prevent contact with the platform.
The portion of the tail line that hangs free below the scaffold shall
be guided or retained, or both, so that it does not become grounded;
(f)(17)(iii)
Each
hoist shall be covered with insulated protective covers;
(f)(17)(iv)
In
addition to a work lead attachment required by the welding process, a
grounding conductor shall be connected from the scaffold to the structure.
The size of this conductor shall be at least the size of the welding process
work lead, and this conductor shall not be in series with the welding
process or the work piece;
(f)(17)(v)
If
the scaffold grounding lead is disconnected at any time, the welding machine
shall be shut off; and
(f)(17)(vi)
An
active welding rod or uninsulated welding lead shall not be allowed to
contact the scaffold or its suspension system.
..1926.451(g)
(g)
"Fall
protection."
(g)(1)
Each
employee on a scaffold more than 10 feet (3.1 m) above a lower level shall
be protected from falling to that lower level. Paragraphs (g)(1)(i) through
(vii) of this section establish the types of fall protection to be provided
to the employees on each type of scaffold. Paragraph (g)(2) of this section
addresses fall protection for scaffold erectors and dismantlers.
Note
to paragraph (g)(1): The fall protection requirements for employees installing
suspension scaffold support systems on floors, roofs, and other elevated
surfaces are set forth in subpart M of this part.
(g)(1)(i)
Each
employee on a boatswains' chair, catenary scaffold, float scaffold, needle
beam scaffold, or ladder jack scaffold shall be protected by a personal
fall arrest system;
(g)(1)(ii)
Each
employee on a single-point or two-point adjustable suspension scaffold
shall be protected by both a personal fall arrest system and guardrail
system;
(g)(1)(iii)
Each
employee on a crawling board (chicken ladder) shall be protected by a
personal fall arrest system, a guardrail system (with minimum 200 pound
toprail capacity), or by a three-fourth inch (1.9 cm) diameter grabline
or equivalent handhold securely fastened beside each crawling board;
(g)(1)(iv)
Each
employee on a self-contained adjustable scaffold shall be protected by
a guardrail system (with minimum 200 pound toprail capacity) when the
platform is supported by the frame structure, and by both a personal fall
arrest system and a guardrail system (with minimum 200 pound toprail capacity)
when the platform is supported by ropes;
..1926.451(g)(1)(v)
(g)(1)(v)
Each
employee on a walkway located within a scaffold shall be protected by
a guardrail system (with minimum 200 pound toprail capacity) installed
within 9 1/2 inches (24.1 cm) of and along at least one side of the walkway.
(g)(1)(vi)
Each
employee performing overhand bricklaying operations from a supported scaffold
shall be protected from falling from all open sides and ends of the scaffold
(except at the side next to the wall being laid) by the use of a personal
fall arrest system or guardrail system (with minimum 200 pound toprail
capacity).
(g)(1)(vii)
For
all scaffolds not otherwise specified in paragraphs (g)(1)(i) through
(g)(1)(vi) of this section, each employee shall be protected by the use
of personal fall arrest systems or guardrail systems meeting the requirements
of paragraph (g)(4) of this section.
(g)(2)
Effective
September 2, 1997, the employer shall have a competent person determine
the feasibility and safety of providing fall protection for employees
erecting or dismantling supported scaffolds. Employers are required to
provide fall protection for employees erecting or dismantling supported
scaffolds where the installation and use of such protection is feasible
and does not create a greater hazard.
..1926.451(g)(3)
(g)(3)
In
addition to meeting the requirements of 1926.502(d), personal fall arrest
systems used on scaffolds shall be attached by lanyard to a vertical lifeline,
horizontal lifeline, or scaffold structural member. Vertical lifelines
shall not be used when overhead components, such as overhead protection
or additional platform levels, are part of a single-point or two-point
adjustable suspension scaffold.
(g)(3)(i)
When
vertical lifelines are used, they shall be fastened to a fixed safe point
of anchorage, shall be independent of the scaffold, and shall be protected
from sharp edges and abrasion. Safe points of anchorage include structural
members of buildings, but do not include standpipes, vents, other piping
systems, electrical conduit, outrigger beams, or counterweights.
(g)(3)(ii)
When
horizontal lifelines are used, they shall be secured to two or more structural
members of the scaffold, or they may be looped around both suspension
and independent suspension lines (on scaffolds so equipped) above the
hoist and brake attached to the end of the scaffold. Horizontal lifelines
shall not be attached only to the suspension ropes.
(g)(3)(iii)
When
lanyards are connected to horizontal lifelines or structural members on
a single-point or two-point adjustable suspension scaffold, the scaffold
shall be equipped with additional independent support lines and automatic
locking devices capable of stopping the fall of the scaffold in the event
one or both of the suspension ropes fail. The independent support lines
shall be equal in number and strength to the suspension ropes.
..1926.451(g)(3)(iv)
(g)(3)(iv)
Vertical
lifelines, independent support lines, and suspension ropes shall not be
attached to each other, nor shall they be attached to or use the same
point of anchorage, nor shall they be attached to the same point on the
scaffold or personal fall arrest system.
(g)(4)
Guardrail
systems installed to meet the requirements of this section shall comply
with the following provisions (guardrail systems built in accordance with
Appendix A to this subpart will be deemed to meet the requirements of
paragraphs (g)(4)(vii), (viii), and (ix) of this section):
(g)(4)(i)
Guardrail
systems shall be installed along all open sides and ends of platforms.
Guardrail systems shall be installed before the scaffold is released for
use by employees other than erection/dismantling crews.
(g)(4)(ii)
The
top edge height of toprails or equivalent member on supported scaffolds
manufactured or placed in service after January 1, 2000 shall be installed
between 38 inches (0.97 m) and 45 inches (1.2 m) above the platform surface.
The top edge height on supported scaffolds manufactured and placed in
service before January 1, 2000, and on all suspended scaffolds where both
a guardrail and a personal fall arrest system are required shall be between
36 inches (0.9 m) and 45 inches (1.2 m). When conditions warrant, the
height of the top edge may exceed the 45-inch height, provided the guardrail
system meets all other criteria of paragraph (g)(4).
..1926.451(g)(4)(iii)
(g)(4)(iii)
When
midrails, screens, mesh, intermediate vertical members, solid panels,
or equivalent structural members are used, they shall be installed between
the top edge of the guardrail system and the scaffold platform.
(g)(4)(iv)
When
midrails are used, they shall be installed at a height approximately midway
between the top edge of the guardrail system and the platform surface.
(g)(4)(v)
When
screens and mesh are used, they shall extend from the top edge of the
guardrail system to the scaffold platform, and along the entire opening
between the supports.
(g)(4)(vi)
When
intermediate members (such as balusters or additional rails) are used,
they shall not be more than 19 inches (48 cm) apart.
(g)(4)(vii)
Each
toprail or equivalent member of a guardrail system shall be capable of
withstanding, without failure, a force applied in any downward or horizontal
direction at any point along its top edge of at least 100 pounds (445
n) for guardrail systems installed on single-point adjustable suspension
scaffolds or two-point adjustable suspension scaffolds, and at least 200
pounds (890 n) for guardrail systems installed on all other scaffolds.
(g)(4)(viii)
When
the loads specified in paragraph (g)(4)(vii) of this section are applied
in a downward direction, the top edge shall not drop below the height
above the platform surface that is prescribed in paragraph (g)(4)(ii)
of this section.
..1926.451(g)(4)(ix)
(g)(4)(ix)
Midrails,
screens, mesh, intermediate vertical members, solid panels, and equivalent
structural members of a guardrail system shall be capable of withstanding,
without failure, a force applied in any downward or horizontal direction
at any point along the midrail or other member of at least 75 pounds (333
n) for guardrail systems with a minimum 100 pound toprail capacity, and
at least 150 pounds (666 n) for guardrail systems with a minimum 200 pound
toprail capacity.
(g)(4)(x)
Suspension
scaffold hoists and non-walk-through stirrups may be used as end guardrails,
if the space between the hoist or stirrup and the side guardrail or structure
does not allow passage of an employee to the end of the scaffold.
(g)(4)(xi)
Guardrails
shall be surfaced to prevent injury to an employee from punctures or lacerations,
and to prevent snagging of clothing.
(g)(4)(xii)
The
ends of all rails shall not overhang the terminal posts except when such
overhang does not constitute a projection hazard to employees.
(g)(4)(xiii)
Steel
or plastic banding shall not be used as a toprail or midrail.
(g)(4)(xiv)
Manila
or plastic (or other synthetic) rope being used for toprails or midrails
shall be inspected by a competent person as frequently as necessary to
ensure that it continues to meet the strength requirements of paragraph
(g) of this section.
..1926.451(g)(4)(xv)
(g)(4)(xv)
Crossbracing
is acceptable in place of a midrail when the crossing point of two braces
is between 20 inches (0.5 m) and 30 inches (0.8 m) above the work platform
or as a toprail when the crossing point of two braces is between 38 inches
(0.97 m) and 48 inches (1.3 m) above the work platform. The end points
at each upright shall be no more than 48 inches (1.3 m) apart.
(h)
"Falling
object protection."
(h)(1)
In
addition to wearing hardhats each employee on a scaffold shall be provided
with additional protection from falling hand tools, debris, and other
small objects through the installation of toeboards, screens, or guardrail
systems, or through the erection of debris nets, catch platforms, or canopy
structures that contain or deflect the falling objects. When the falling
objects are too large, heavy or massive to be contained or deflected by
any of the above-listed measures, the employer shall place such potential
falling objects away from the edge of the surface from which they could
fall and shall secure those materials as necessary to prevent their falling.
(h)(2)
Where
there is a danger of tools, materials, or equipment falling from a scaffold
and striking employees below, the following provisions apply:
(h)(2)(i)
The
area below the scaffold to which objects can fall shall be barricaded,
and employees shall not be permitted to enter the hazard area; or
..1926.451(h)(2)(ii)
(h)(2)(ii)
A
toeboard shall be erected along the edge of platforms more than 10 feet
(3.1 m) above lower levels for a distance sufficient to protect employees
below, except on float (ship) scaffolds where an edging of 3/4 x 1 1/2
inch (2 x 4 cm) wood or equivalent may be used in lieu of toeboards;
(h)(2)(iii)
Where
tools, materials, or equipment are piled to a height higher than the top
edge of the toeboard, paneling or screening extending from the toeboard
or platform to the top of the guardrail shall be erected for a distance
sufficient to protect employees below; or
(h)(2)(iv)
A
guardrail system shall be installed with openings small enough to prevent
passage of potential falling objects; or
(h)(2)(v)
A
canopy structure, debris net, or catch platform strong enough to withstand
the impact forces of the potential falling objects shall be erected over
the employees below.
(h)(3)
Canopies,
when used for falling object protection, shall comply with the following
criteria:
(h)(3)(i)
Canopies
shall be installed between the falling object hazard and the employees.
..1926.451(h)(3)(ii)
(h)(3)(ii)
When
canopies are used on suspension scaffolds for falling object protection,
the scaffold shall be equipped with additional independent support lines
equal in number to the number of points supported, and equivalent in strength
to the strength of the suspension ropes.
(h)(3)(iii)
Independent
support lines and suspension ropes shall not be attached to the same points
of anchorage.
(h)(4)
Where
used, toeboards shall be:
(h)(4)(i)
Capable
of withstanding, without failure, a force of at least 50 pounds (222 n)
applied in any downward or horizontal direction at any point along the
toeboard (toeboards built in accordance with Appendix A to this subpart
will be deemed to meet this requirement); and
(h)(4)(ii)
At
least three and one-half inches (9 cm) high from the top edge of the toeboard
to the level of the walking/working surface. Toeboards shall be securely
fastened in place at the outermost edge of the platform and have not more
than 1/4 inch (0.7 cm) clearance above the walking/working surface. Toeboards
shall be solid or with openings not over one inch (2.5 cm) in the greatest
dimension.
Back
to Contents
|