Current through all regulations passed and filed through September 16, 2024
(B) Definitions.
(1) "Bearer" means a horizontal member of a
scaffold upon which the platform rests and which may be supported by
ledgers.
(2) "Boatswain's chair"
means a seat supported by slings attached to a suspended rope, designed to
accommodate one employee in a sitting position.
(3) "Brace" means a tie that holds one
scaffold member in a fixed position with respect to another member.
(4) "Bricklayer's square scaffold" means a
scaffold the platform of which is supported on built-up squares secured to each
other by full and continuous diagonal bracing.
(5) "Carpenter's bracket scaffold" means a
scaffold the platform of which is supported on triangular braced brackets
fastened to the side of the structure.
(6) "Chimney, stack, or tank bracket
scaffold" means a scaffold composed of a platform supported by wood or steel
brackets, hooked over a steel wire rope which surrounds the circumference of
the chimney, stack, or tank.
(7)
"Coupler" means a device for locking together the component parts of a tubular
metal scaffold.
(8) "Double pole or
independent pole scaffold" means a scaffold supported from the base by a double
row of uprights, independent of support from the walls and constructed of
uprights, ledgers, horizontal platform bearers, and diagonal bracing.
(9) "Elevating assembly" means a mechanical,
hydraulic, or other type of mechanism used to elevate and lower a work
platform.
(10) "Float or ship
scaffold" means a scaffold hung from overhead supports by means of ropes and
consisting of a platform having diagonal bracing underneath, resting upon and
fastened to two parallel plank bearers at right angles to the span.
(11) "Foot scaffold" means a scaffold used to
give additional height, the platform of which does not exceed eighteen inches
above the supporting surface.
(12)
"Heavy duty scaffold" means a scaffold designed and constructed to carry a
working load in excess of fifty pounds but no more than seventy-five pounds per
square foot.
(13) "Horizontal wire
rope supported scaffold" means a scaffold the platform of which is supported at
two or more points by horizontal wire ropes.
(14) "Horse scaffold" means a scaffold or
light or medium duty, composed of saw horses
supporting a work platform.
(15)
"Interior hung scaffold" means a scaffold suspended from the ceiling or roof
structure.
(16) "Ladder jack
scaffold" means a light duty scaffold supported by brackets attached to
ladders.
(17) "Lean to, or shore,
scaffold", use prohibited (see paragraph (C)(16) of this rule), means scaffold
the platform of which is supported on members consisting of a putlog or bearer,
knee braced to two diverging inclined legs that are in a plane substantially
transverse to the putlog and that support the outer end of the putlog or
bearer, while the inner end of the bearer or putlog rests on or against the
structure or on a bearing block attached to the structure.
(18) "Ledgers" or "stringers" means a
horizontal scaffold member which extends from post to post at right angles to
the putlogs or bearers, supports the putlogs or bearers, and forms a tie
between the posts and becomes a part of the scaffold bracing.
(19) "Light duty scaffold" means a scaffold
designed and constructed to carry a working load of no more than twenty-five
pounds per square foot.
(20)
"Manually propelled mobile scaffold" means a portable rolling scaffold equipped
with casters.
(21) "Mason's
adjustable multiple-point suspension scaffold" means a scaffold having a
continuous platform supported by bearers suspended by wire rope from overhead
supports, so arranged and operated as to permit the raising or lowering of the
platform to desired working positions.
(22) "Maximum rated load" means the total of
all loads including the working load, the weight of the scaffold, and such
other loads as may be reasonably anticipated.
(23) "Medium duty scaffold" means a scaffold
designed and constructed to carry a working load in excess of twenty-five
pounds but no more than fifty pounds per square foot.
(24) "Needle beam scaffold" means a
cantilevered light duty scaffold consisting of two parallel horizontal beam
called needle beams supporting a platform.
(25) "Outrigger scaffold" means a scaffold
supported by outriggers or thrustouts projecting beyond the wall or face of the
building or structure, the inboard ends of which are secured inside the wall or
face of such building or structure.
(26) "Pick, or kick, plank" means a platform,
similar in construction to a narrow ladder with light decking strung upon and
attached to the rungs, which rests upon horizontal and parallel stringers, or
other bearers, and is movable along the course of the stringer.
(27) "Platform" means the temporary flat
working surface used to support employees, material, and equipment.
(28) "Putlog" means a scaffold member upon
which the platform rests (also see "bearer").
(29) "Runner" means the lengthwise horizontal
bracing or bearing members, or both.
(30) "Scaffold" means any temporary elevated
platform and its supporting structure used for supporting employees, materials,
or equipment.
(31) "Single-point
adjustable suspension scaffold" means a manually or power operated unit
designed for light duty use, supported by a single wire rope from an overhead
support so arranged and operated as to permit the raising or lowering of
platform to desired working positions.
(32) "Single-pole scaffold" means platforms
resting on putlogs or cross beams, the outside ends of which are supported on
ledgers secured to a single row of posts or uprights, and the inner ends of
which are supported on or in a wall.
(33) "Stack bracket scaffold" - see "chimney
bracket scaffold".
(34) "Suspended
scaffold" means a scaffold supported from above, the platform of which is
supported at more than two points from overhead outriggers which are fastened
to the framework of the structure.
(35) "Tank bracket scaffold" - see "chimney
bracket scaffold".
(36) "Tube and
coupler scaffold" means an assembly consisting of tubing which serves as posts,
bearers, braces, ties, and runner, a base supporting the posts, and special
couplers which serve to connect the uprights and to join the various
members.
(37) "Tubular welded frame
scaffold" means a sectional panel or frame metal scaffold built up of
prefabricated welded sections which consists of posts and horizontal bearers
with intermediate members.
(38)
"Two-point suspension scaffold" or "swinging scaffold" means a scaffold the
platform of which is supported by stirrups or hangers at two points to permit
raising or lowering, suspended from overhead supports.
(39) "Window jack scaffold" means a scaffold
the platform of which is supported by a jack or thrustout which projects
through a window opening.
(40)
"Working load" means the load on the scaffold imposed by employees, material,
and equipment.
(C)
General requirements for all scaffolds.
See appendix to this rule for examples of various scaffolds
mentioned throughout this rule.
(1)
The footing or anchorage for scaffolds shall be sound, rigid, and capable of
supporting the load without settling or displacement. Unstable or loose objects
shall not be used to support scaffolds.
(2) Scaffolds and their components shall be
capable of supporting without failure no less than four times the maximum rated
load.
(3) Any scaffold including
accessories, such as braces, brackets, trusses, screw legs, ladders, etc.,
damaged or weakened from any cause shall be immediately repaired or
replaced.
(4) Guardrails and
toeboards.
Standard guardrails and toeboards shall be installed on all
open sides and ends of platforms more than ten feet above the ground or floor,
except on needle beam scaffolds and floats.
(5)
Where employees are required to work
or pass under the scaffold, each employee 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 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.
(6)
Nails provided for the construction of scaffolds shall be no less than
eight-penny common.
(7) All
planking shall be "Scaffold Grade," or equivalent, as recognized by approved
grading rules for the species of wood used.
(8) All planking of platforms shall be
overlapped a minimum of twelve inches or secured from movement.
(9) An access ladder or equivalent safe
access shall be provided for all scaffolds.
(10) Scaffold planks shall extend over end
supports no less than six inches and no more than twelve inches.
(11) The poles, legs, or uprights of
scaffolds shall be plumb and securely and rigidly braced to prevent swaying and
displacement.
(12) Overhead
protection shall be provided for employees on a scaffold exposed to hazards
from overhead.
(13) Reasonable care
shall be taken to maintain all scaffold surfaces free of debris and slippery
substances.
(14) No welding,
burning, riveting, or open flame work shall be performed on any scaffolding
suspended by means of fiber or synthetic rope. Only fiber or synthetic ropes,
properly treated or protected, shall be used for or near any work involving the
use of corrosive substances or chemicals.
(15) Wire, synthetic, or fiber rope used for
scaffold suspension shall be capable of supporting no less than six times the
maximum rated load.
(16) The use of
shore or lean-to scaffolds is prohibited.
(17) When there is danger of material being
hoisted striking against the scaffold, a tag line shall be provided.
(18) The free ends of fall lines from
scaffolds shall be guarded.
(D) Wood pole scaffolds.
See appendix to this rule for examples of wood pole
scaffolds.
(1) Scaffold poles shall
bear on a foundation of sufficient size and strength to spread the load from
the pole over a sufficient area to prevent settlement. All poles shall be set
plumb.
(2) Where poles are spliced,
the ends shall be squared and the upper section shall rest squarely on the
lower section. Wood splice plates shall be provided on no less than two
adjacent sides and shall be no less than four feet in length, overlapping the
abutted ends equally, and have the same width and no less than the
cross-sectional area of the pole. Splice plates or other materials of
equivalent strength may be used.
(3) Independent pole scaffolds shall be set
as near to the wall of the building as practicable.
(4) All pole scaffolds shall be securely
guyed or tied to the building or structure.
Where the height or length exceeds twenty-five feet, the
scaffold shall be secured at intervals no greater than twenty-five feet
vertically and horizontally.
(5) Putlogs or bearers shall be set with the
greater dimension vertical, long enough to project over the ledgers of the
inner and outer rows of poles no less than three inches for proper
support.
(6) Every wooden putlog on
single pole scaffolds shall be reinforced with a three-sixteenths - by two-inch
steel strip, or equivalent, secured to its lower edge throughout its entire
length.
(7) Ledgers shall be long
enough to extend over two pole spaces. Ledgers shall not be spliced between the
poles. Ledgers shall be reinforced by bearing blocks securely fastened to the
side of the pole to form a support for the ledger.
(8) Diagonal bracing shall be provided to
prevent the poles from moving in a direction parallel with the wall of the
building, and from buckling.
(9)
Cross bracing shall be provided between the inner and outer sets of poles in
independent pole scaffolds. The free ends of pole scaffolds shall be cross
braced.
(10) Full diagonal face
bracing shall be erected across the entire face of pole scaffolds in both
directions. The braces shall be spliced only at the poles. The inner row of
poles on medium and heavy duty scaffolds shall be braced in similar
manner.
(11) Platform planks shall
be laid with their edges butted together so the platform shall be tight with no
spaces through which tools or fragments of material can fall.
(12) Where planking is lapped, each plank
shall lap its end support no less than twelve inches. Where the ends of planks
abut each other to form a flush floor, the butt joint shall be at the
centerline of a pole. The abutted ends shall rest on separate bearers.
Intermediate beams shall be provided where necessary to prevent dislodgment of
planks due to deflection, and the ends shall be secured to prevent their
dislodgment.
(13) When a scaffold
materially changes its direction, the platform planks shall be laid to prevent
tipping. The planks that meet the corner putlog at an angle shall be laid
first, extending over the diagonally placed putlog far enough to have a good
safe bearing, but not far enough to involve any danger from tipping. The
planking running in the opposite direction at an angle shall be laid so as to
extend over and rest on the first layer of planking.
(14) When moving platforms to the next level,
the old platform shall be left undisturbed until the new putlogs or bearers
have been set in place, ready to receive the platform planks.
(15) All wood pole scaffolds sixty feet or
less in height shall be constructed and erected in accordance with "Tables 10-1
to 10-6." If they are over sixty feet in height, they shall be designed by a
professional engineer competent in this field, and shall be constructed and
erected in accordance with such design.
Table 10-1. Minimum nominal size and maximum spacing of members
of single-pole scaffolds - light duty.
|
|
Maximum height of scaffold
|
|
|
20 ft.
|
60 ft.
|
|
Uniformly distributed load
|
Not to exceed 25 p.s.f.
|
|
|
Poles or uprights
|
2 x 4 in.
|
4 x 4 in.
|
|
Pole spacing (longitudinal)
|
6 ft. 0 in.
|
10 ft. 0 in.
|
|
Maximum width of scaffold
|
5 ft. 0 in.
|
5 ft. 0 in.
|
|
Bearers or putlogs to 3 ft. 0 in. width
|
2 x 4 in.
|
2 x 4 in.
|
|
Bearers or putlogs to 5 ft. 0 in. width
|
2 x 6 in. or 3 x 4 in.
|
2 x 6 in. or 3 x 4 in. (rough).
|
|
Ledgers
|
1 x 4 in.
|
1 1/4 x 9 in.
|
|
Planking
|
1 1/4 x 9 in. (rough)
|
2 x 10 in.
|
|
Vertical spacing of horizontal members
|
7 ft. 0 in.
|
9 ft. 0 in.
|
|
Bracing, horizontal and diagonal
|
1 x 4 in.
|
1 x 4 in.
|
|
Tie-ins
|
1 x 4 in.
|
1 x 4 in.
|
|
Toeboards
|
4 in. high (minimum)
|
4 in. high (minimum).
|
|
Guardrails
|
2 x 4 in.
|
2 x 4 in.
|
All members except planking shall be used on edge.
Table 10-2. Minimum nominal size and maximum spacing of members
of single-pole scaffolds - medium duty.
|
Uniformly distributed load.
|
Not to exceed 50 p.s.f.
|
|
Maximum height of scaffolds.
|
60 ft.
|
|
Poles or uprights
|
4 x 4 in.
|
|
Pole spacing (longitudinal).
|
8 ft. 0 in.
|
|
Maximum width of scaffold.
|
5 ft. 0 in.
|
|
Bearers or putlogs
|
2 x 10 in. or 3 x 4 in.
|
|
Spacing of bearers or putlogs.
|
8 ft. 0 in.
|
|
Ledgers
|
2 x 10 in.
|
|
Vertical spacing of horizontal members.
|
7 ft. 0 in.
|
|
Bracing, horizontal
|
1 x 6 in. or 1 1/4 x 4 in.
|
|
Bracing, diagonal
|
1 x 4 in.
|
|
Tie-ins
|
1 x 4 in.
|
|
Planking
|
2 x 10 in.
|
|
Toeboards
|
4 in. high (minimum).
|
|
Guardrails
|
2 x 4 in.
|
All members except planking shall be used on edge.
Table 10-3. Minimum nominal size and maximum spacing of members
of single-pole scaffolds - heavy duty.
|
Uniformly distributed load.
|
Not to exceed 75 p.s.f.
|
|
Maximum height of scaffold.
|
60 ft.
|
|
Poles or uprights
|
4 x 6 in.
|
|
Pole spacing (longitudinal).
|
6 ft. 0 in.
|
|
Maximum width of scaffold.
|
5 ft. 0 in.
|
|
Bearers or putlogs
|
2 x 10 in. or 3 x 5 in.
|
|
Spacing of bearers or putlogs.
|
6 ft. 0 in.
|
|
Ledgers
|
2 x 10 in.
|
|
Vertical spacing of horizontal members.
|
6 ft. 6 in.
|
|
Bracing, horizontal and diagonal.
|
2 x 4 in.
|
|
Tie-ins
|
1 x 4 in.
|
|
Planking
|
2 x 10 in.
|
|
Toeboards
|
4 in. high (minimum).
|
|
Guardrails
|
2 x 4 in.
|
All members except planking shall be used on edge.
Table 10-4. Minimum nominal size and maximum spacing of members
of independent pole scaffold - light duty.
|
|
Maximum height of scaffold
|
|
|
20 ft.
|
60 ft.
|
|
Uniformly distributed load
|
Not to exceed 25 p.s.f.
|
|
|
Poles or uprights
|
2 x 4 in.
|
4 x 4 in.
|
|
Pole spacing (longitudinal)
|
6 ft. 0 in.
|
10 ft. 0 in.
|
|
Pole spacing (transverse)
|
6 ft. 0 in.
|
10 ft. 0 in.
|
|
Ledgers
|
1 1/4 x 4 in.
|
1 1/4 x 9 in.
|
|
Bearers to 3 ft. 0 in. span
|
2 x 4 in.
|
2 x 4 in.
|
|
Bearers to 10 ft. 0 in. span
|
2 x 6 in. or 3 x 4 in.
|
2 x 10 (rough) or 3 x 8 in.
|
|
Planking
|
1 1/4 x 9 in.
|
2 x 10 in.
|
|
Vertical spacing of horizontal members
|
7 ft. 0 in.
|
7 ft. 0 in.
|
|
Bracing, horizontal and diagonal
|
1 x 4 in.
|
1 x 4 in.
|
|
Tie-ins
|
1 x 4 in.
|
1 x 4 in.
|
|
Toeboards
|
4 in. high
|
4 in. high (minimum)
|
|
Guardrails
|
2 x 4 in.
|
2 x 4 in.
|
All members except planking shall be used on edge.
Table 10-5. Minimum nominal size and maximum spacing of members
of independent pole scaffolds - medium duty.
|
Uniformly distributed load.
|
Not to exceed 50 p.s.f.
|
|
Maximum height of scaffold.
|
60 ft.
|
|
Poles or uprights
|
4 x 4 in.
|
|
Pole spacing (longitudinal).
|
8 ft. 0 in.
|
|
Pole spacing (transverse).
|
8 ft. 0 in.
|
|
Ledgers
|
2 x 10 in.
|
|
Vertical spacing of horizontal members.
|
6 ft. 0 in.
|
|
Spacing of bearers
|
8 ft. 0 in.
|
|
Bearers
|
2 x 10 in.
|
|
Bracing, horizontal
|
1 x 6 in. or 1 1/4 x 4 in.
|
|
Bracing, diagonal
|
1 x 4 in.
|
|
Tie-ins
|
1 x 4 in.
|
|
Planking
|
2 x 10 in.
|
|
Toeboards
|
4 in. high (minimum).
|
|
Guardrails
|
2 x 4 in.
|
All members except planking shall be used on edge.
Table 10-6. Minimum nominal size and maximum spacing of members
of independent pole scaffold - heavy duty.
|
Uniformly distributed load.
|
Not to exceed 75 p.s.f.
|
|
Maximum height of scaffold.
|
60 ft.
|
|
Poles or uprights
|
4 x 4 in.
|
|
Pole spacing (longitudinal).
|
6 ft. 0 in.
|
|
Pole spacing (transverse).
|
8 ft. 0 in.
|
|
Ledgers
|
2 x 10 in.
|
|
Vertical spacing of horizontal members.
|
6 ft. 0 in.
|
|
Bearers
|
2 x 10 in. (rough).
|
|
Bracing, horizontal and diagonal.
|
2 x 4 in.
|
|
Tie-ins
|
1 x 4 in.
|
|
Planking
|
2 x 10 in.
|
|
Toeboards
|
4 in. high (minimum).
|
|
Guardrails
|
2 x 4 in.
|
All members except planking shall be used on edge.
(E) Tube and coupler
scaffolds.
(1) The material used for couplers
shall be of a structural type, such as drop-forged steel, malleable iron, or
structural grade aluminum.
(2) A
light duty tube and coupler scaffold shall have all posts, bearers, runners,
and bracing of nominal two-inch outside-diameter (O.D.) steel tubing. The posts
shall be spaced no more than six feet apart in width and ten feet apart in
length. Other structural metals when used must be designed to carry an
equivalent load. No dissimilar metals shall be used together.
(3) A medium duty tube and coupler scaffold
shall consist of no less than nominal two-inch O.D. steel tubing in all posts,
runners, and bracing. Where the posts are spaced no farther apart than five
feet by eight feet, the bearers shall also be no less than nominal two-inch
O.D. steel tubing. Where the posts are spaced at greater distances apart than
five feet by eight feet, the bearers shall be of not less than nominal two and
one-half inch O.D. steel tubing but, in no event, may the posts of a medium
duty tube and coupler scaffold be spaced farther apart than six feet by eight
feet. Other structural metals, when used, must be capable of carrying a load
equivalent to the load supportable by the prescribed tube and coupler scaffold.
No dissimilar metals shall be used together.
(4) A heavy duty tube and coupler scaffold
shall have all posts, runners, and bracing of nominal two-inch O.D. steel
tubing, with the posts spaced no more than six feet by six feet six inches.
Other structural metals, when used, must be designed to carry an equivalent
load. No dissimilar metals shall be used together.
(5) Tube and coupler scaffolds shall be
limited in heights and working levels to those permitted in Tables 10-7 to
10-9. Drawings and specifications of all tube and coupler scaffolds above the
limitations in Tables 10-7 to 10-9 shall be designed by a qualified engineer
competent in this field.
(6) Posts
shall be accurately spaced, erected on suitable bases, and maintained
plumb.
(7) Runners shall be erected
along the length of the scaffold, located on both the inside and the outside
posts at even heights. Runners shall be interlocked to the inside and the
outside posts at even heights. Runners shall be interlocked to form continuous
lengths and coupled to each post. The bottom runners shall be located as close
to the base as possible. Runners shall be placed no more than six feet six
inches on centers.
(8) Bearers
shall be installed transversely between posts and shall be securely coupled to
the posts bearing on the runner coupler. When coupled directly to the runners,
the coupler must be kept as close to the posts as possible.
(9) Bearers shall extend past the post and
runners.
(10) Cross bracing shall
be installed across the width of the scaffold no less than every third set of
posts horizontally and every fourth runner vertically. Such bracing shall
extend diagonally from the inner and outer runners upward to the next outer and
inner runners.
(11) Longitudinal
diagonal bracing on the inner and outer rows of poles shall be installed at
approximately a forty-five degree angle from near the base of the first outer
post upward to the extreme top of the scaffold. Where the longitudinal length
of the scaffold permits, such bracing shall be duplicated beginning at every
fifth post. In a similar manner, longitudinal diagonal bracing shall also be
installed from the last post extending back and upward toward the first post.
Where conditions preclude the attachment of this bracing to the posts, it may
be attached to the runners.
(12)
The entire scaffold shall be tied to and securely braced against the building
at intervals not to exceed thirty feet horizontally and twenty-six feet
vertically.
Table 10-7. Tube and coupler scaffolds - light duty
|
Uniformly distributed load
|
Not to exceed 25 p.s.f.
|
|
Post spacing (longitudinal)
|
10 ft. 0 in.
|
|
Post spacing (transverse)
|
|
|
Working levels
|
Additional planked levels
|
Maximum height
|
|
1
|
8
|
125 ft.
|
|
2
|
4
|
125 ft.
|
|
3
|
0
|
91 ft. 0 in.
|
Table 10-8. Tube and coupler scaffolds - medium duty
|
Uniformly distributed load
|
Not to exceed 50 p.s.f
|
|
Post spacing (longitudinal)
|
8 ft. 6 in.
|
|
Post spacing (transverse)
|
6 ft. 0 in
|
|
Working levels
|
Additional planked levels
|
Maximum height
|
|
1
|
6
|
125 ft
|
|
2
|
0
|
78 ft. 0 in.
|
Table 10-9. Tube and coupler scaffolds - heavy duty
|
Uniformly distributed load
|
Not to exceed 75 p.s.f.
|
|
Post spacing (longitudinal)
|
6 ft. 6 in.
|
|
Post spacing (transverse)
|
6 ft. 0 in.
|
|
Working levels
|
Additional planked levels
|
Maximum height
|
|
1
|
6
|
125 ft.
|
(F) Tubular welded frame scaffolds.
(1) Scaffolds shall be properly braced by
diagonal braces for securing vertical members together laterally, and the cross
braces shall be of such length as will automatically square and align vertical
members so that the erected scaffold is always plumb, square, and rigid. All
brace connections shall be made secure.
(2) Scaffold legs shall be set on adjustable
bases or plain bases placed on mud sills or other adequate
foundations.
(3) The frames shall
be placed one on top of the other with coupling or stacking pins to provide
proper vertical alignment of the legs.
(4) Where uplift may occur, panels shall be
locked together vertically by pins or other equivalent suitable
means.
(5) Supported scaffolds with
a height to base width (including outrigger supports if used) ratio of more
than four to one shall be secured to the building or structure at intervals not
to exceed thirty feet horizontally and twenty-six feet vertically.
(6) Maximum permissible spans or planking
shall be in conformity with paragraph(C)(7) of this rule.
(G) Manually propelled mobile scaffolds.
(1) When free-standing mobile scaffold towers
are used, the height of the work platform shall not exceed four times the
minimum base dimension.
(2) Casters
shall be properly designed for strength and dimensions to support four times
the maximum rated load. All casters shall be provided with a locking device to
hold the scaffold in position.
(3)
Scaffolds shall be properly braced by cross bracing and horizontal bracing
conforming with paragraph (F)(1) of this rule.
(4) Platforms shall be tightly planked for
the full width of the scaffold except for necessary entrance opening. Platforms
shall be secured in place.
(5) A
ladder or stairway shall be provided for proper access and exit and shall be
affixed or built into the scaffold and so located that when in use it will not
have a tendency to tip the scaffold. A landing platform must be provided at
intervals not to exceed thirty-five feet.
(6) Provision shall be made to stabilize the
tower during movement from one location to another.
(7) The employer shall not require employees
to ride on manually propelled scaffolds unless the following conditions exist:
(a) The floor or surface is within three
degrees of level and free from pits, holes, or obstructions;
(b) When ready for rolling the height of the
work platform shall not exceed two times the narrowest dimension of the base;
when outriggers are used they shall be included in the base dimension and shall
be installed on both sides of the staging;
(c) The wheels are equipped with rubber or
similar resilient tires;
(d) All
tools and materials are secured or removed from the platform before the mobile
scaffold is moved.
(H) Elevated work platforms and
self-propelled elevated work platforms.
(1)
The minimum rated work load of a platform shall be no less than two hundred
fifty pounds. The work platform and all structural components shall have a
factor of safety of no less than four.
(2) Any work platform when raised to its
maximum working height shall be capable of sustaining without reaching
instability, a horizontal force of fifty pounds applied to any point on the
platform while the platform is carrying the working load.
(3) The base shall not be used or placed on
an inclined surface unless leveled by a device that is part of the
unit.
(4) Work platform elevating
assemblies.
(a) Factors of safety of elevating
assembly.
(i) Where the platform is supporting
its working load by a system of wire ropes or lift chains, or both, the factor
of safety of the wire or chain shall be no less than six.
(ii) All critical components of a hydraulic
or pneumatic system used in a work platform shall have a bursting strength that
exceeds the pressure attained when the system is subjected to the equivalent of
four times the maximum rated load. Critical components are those in which a
failure would result in a free fall. All noncritical hydraulic components shall
have a bursting factor of safety of no less than two.
(b) Systems protection.
(i) Where the elevation of the platform is
accomplished by an electromechanical assembly, or a hydraulic or pneumatic
cylinder assembly, the system shall be so equipped as to prevent free fall in
the event of a power failure.
(ii)
Where the elevation of the platform is accomplished by a hydraulic or pneumatic
cylinder assembly, the system shall be so equipped as to prevent free fall in
the event of a hydraulic or pneumatic line failure.
(iii) Where the elevation of the platform is
accomplished by a single hoist cable, the system shall be protected by a
broken-cable safety device.
(iv)
Where the elevation of the platform is accomplished by manual-mechanical or
manual-hydraulic assembly, the assembly shall be equipped to prevent free fall
in case of failure.
(c)
Controls.
(i) Any powered work platform shall
have both upper and lower control devices. Controls shall be plainly marked as
to their function and guarded to prevent accidental operation. The upper
control device shall be in or beside the platform, within easy reach of the
operator. The lower control device shall have the capability to lower the
platform where the operator's safety is in jeopardy.
(ii) Each elevated work platform shall be
equipped with a clear visible instruction plate stating:
(a) Rated capacity;
(b) Maximum platform height;
(c) Special warning or restrictions necessary
for safe operation.
(iii) Protection to personnel.
(a) Pinch points and shear points shall be
guarded with a barrier to prevent accidental or inadvertent entrapment of
personnel while the work platform is being operated.
(b) All rotating shafts, gearing, and other
moving parts shall be guarded.
(I) Outrigger scaffolds.
See appendix to this rule for examples of outrigger
scaffolds.
(1) Outrigger beams shall
extend no more than six feet beyond the face of the building.
The inboard end of the outrigger beams, measured from the
fulcrum point to anchorage point, shall be no less than one and one-half times
the outboard end in length. The beams shall rest on edge, the sides shall be
plumb, and the edges shall be horizontal. The fulcrum point of the beam shall
rest on a secure bearing no less than six inches in each horizontal dimension.
The beam shall be secured in place against movement and shall be securely
braced at the fulcrum point against movement and shall be securely braced at
the fulcrum point against tipping.
(2) The inboard ends of outrigger beams shall
be securely anchored either by means of struts bearing against sills in contact
with the overhead beams or ceiling, or by means of tension members secured to
the floor joists underfoot, or by both if necessary. The inboard ends of
outrigger beams shall be secured against tipping and the entire supporting
structure shall be securely braced in both directions to prevent any horizontal
movement.
(3) Unless outrigger
scaffolds are designed by a professional engineer competent in this field, they
shall be constructed and erected in accordance with "Table 10-10." Outrigger
scaffolds, designed by a professional engineer, shall provide equivalent or
greater safeguards than those required herein.
(4) Planking shall be laid tight and shall
extend to within three inches of the building wall. Planking shall be secured
to the beams.
Table 10-10. Minimum nominal size and maximum spacing of
members of outrigger scaffolds.
|
|
Light duty
|
Medium duty
|
|
Maximum scaffold load.
|
25 p.s.f.
|
50 p.s.f.
|
|
Outrigger size
|
2 x 10 in.
|
3 x 10 in.
|
|
Maximum outrigger spacing.
|
10 ft. 0 in.
|
6 ft. 0 in.
|
|
Planking
|
2 x 10 in.
|
2 x 10 in.
|
|
Guardrail
|
2 x 4 in.
|
2 x 4 in.
|
|
Guardrail uprights
|
2 x 4 in.
|
2 x 4 in.
|
|
Toeboards
|
4 in. (minimum).
|
4 in. (minimum).
|
(J) Masons' adjustable multiple-point
suspension scaffolds.
See appendix to this rule for examples of masons' adjustable
multiple-point suspension scaffolds.
(1) The scaffold shall be capable of
sustaining a working load of fifty pounds per square foot and shall not be
loaded in excess of that figure.
(2) The scaffold shall be provided with
hoisting machines that meet the requirements of an approved testing
laboratory.
(3) The platform
shall be supported by wire ropes, capable of supporting no less than six times
the intended load, suspend from overhead outrigger beams.
(4) The scaffold outrigger beams shall
consist of structural metal securely fastened or anchored to the frame or floor
system of the building or structure.
(5) Where an outrigger beam does not project
more than six feet six inches beyond the bearing point, it shall be equivalent
in the strength to no less than a standard seven-inch, fifteen and
three-tenths-pound steel I-beam no less than fifteen feet long.
(6) Where the overhang exceeds six feet six
inches, outrigger beams shall be composed of stronger beams or multiple beams,
providing proportionally greater strength than that required in paragraph
(J)(5) of this rule.
(7) All
outrigger beams shall be set and maintained with their webs in a vertical
position.
(8) A stop bolt shall be
placed at each end of every outrigger beam.
(9) The outrigger beam shall rest on suitable
wood bearing blocks.
(10) The free
end of the suspension wire ropes shall be equipped with proper size thimbles
and secured by splicing or other equivalent means. The running ends shall be
securely attached to the hoisting drum and no less than four turns of wire rope
shall at all times remain on the drum. The use of fiber rope is
prohibited.
(11) Where a single
outrigger beam is used, the steel shackles or clevises with which the wire
ropes are attached to the outrigger beams shall be placed directly over the
hoisting drum.
(12) The scaffold
platform shall be equivalent in strength to no less than two-inch
planking.
(13) When employees are
at work on the scaffold and a hazard exists from overhead, overhead protection
shall be provided on the scaffold, no more than nine feet above the platform,
consisting of two-inch planking, or material of equivalent strength, laid
tight, and extending no less than the width of the scaffold.
(K) Two-point suspension scaffolds
(swinging scaffolds).
See appendix to this rule for examples of swinging
scaffolds.
(1) Two-point suspension
scaffold platforms shall be no more than thirty-six inches wide overall. The
platform shall be securely fastened to the hangers by U-bolts or by other
equivalent means.
(2) The hangers
of two-point suspension scaffolds shall be made of mild steel, or other
equivalent materials, having a cross-sectional area capable of sustaining four
times the maximum rated load, and shall be constructed to accommodate a
guardrail, intermediate rail, and toeboard.
(3) When hoisting machines are used on
two-point suspension scaffolds, such machines shall be of a design tested and
approved by an approved
testing laboratory.
(4)
Employees shall not be required to use a bridge between, or to move directly
from, one swinging scaffold and another unless the platforms are at the same
height, are abutting, and walk through stirrups specifically designed for this
purpose are used.
(5) The roof
irons or hooks shall be of mild steel, or other equivalent material, of proper
size and design, securely installed and anchored. Tiebacks of
three-quarter-inch manila rope, or the equivalent, shall serve as an additional
means of anchorage, installed at right angles to the face of the building,
whenever possible, and secured to a structurally sound portion of the
building.
(6) Two-point suspension
scaffolds shall be suspended by wire, synthetic, or fiber ropes capable of
supporting no less than six times the maximum rated load. All other components
shall be capable of supporting no less than four times the maximum rated
load.
(7) The sheaves of all blocks
shall fit the size and type of rope used.
(8) No more than two employees shall be
required to be on a two-point suspension scaffold designed for a working load
of five hundred pounds at any time. No more than three employees shall be
required to be on a two-point suspension scaffold designed for a working load
of seven hundred pounds, at any time. Each employee shall be protected by an
approved safety belt or harness attached to a lifeline. The lifeline shall be
securely attached to substantial members of the structure (not scaffold) or to
securely rigged lines, which will safely suspend the employee in case of a
fall.
(9) Two-point suspension
scaffolds shall be securely lashed to the building or structure to prevent from
swaying. Window cleaners' anchors shall not be used for this purpose.
(10) The platform of every two-point
suspension scaffold shall be one of the following types:
(a) Ladder-type platforms.
Ladder-type platforms shall be capable of sustaining four times
the maximum rated load and shall be constructed in accordance with "Table
10-11."
(b) Plank-type
platforms.
Plank-type platforms shall be composed of no less than
"Scaffold Grade" two-inch by ten-inch unspliced planks, properly cleated
together on the underside, starting six inches from each end; intervals in
between shall not exceed four feet. The plank-type platform shall not extend
beyond the hangers more than twelve inches. A bar or other effective means
shall be securely fastened to the platform at each end to prevent its slipping
off the hanger. The span between hangers for plank-type platforms shall not
exceed eight feet.
(c)
Beam-type platforms.
Beam-type platforms shall have side stringers of lumber no less
than two inches by six inches set on edge. The span between hangers shall not
exceed twelve feet when beam platforms are used. The flooring shall be
supported on two-inch by six-inch cross beams, laid flat and set into the upper
edge of the stringers with a snug fit, at intervals of no more than four feet,
securely nailed in place. The flooring shall be of one-inch by six-inch
material, or equivalent, properly nailed. Floor boards shall be spaced no more
than one-half-inch apart.
(d) Light metal-type platforms.
Approved light metal-type platforms shall meet the requirements
of paragraph (C)(2) of this rule.
Table 10-11. Schedule for ladder-type platforms.
Click to
view image
(L) Single-point adjustable suspension
scaffolds.
(1) The scaffolding, including
power units or manually operated winches, shall be of an approved type and meet
the requirements of paragraph (C)(2) of this rule.
(2) All power-operated gears and brakes shall
be enclosed.
(3) In addition to the
normal operating brake, all power-driven units shall have an emergency brake
which engages automatically when the normal speed of descent is
exceeded.
(4) The units may be
combined to form a two-point suspension scaffold. Such scaffold shall then
comply with paragraph (K) of this rule.
(5) The supporting cable shall be vertical
for its entire length.
(6)
Suspension methods shall conform to applicable provisions of paragraphs (J) and
(K) of this rule.
(7) The employee
shall be protected by a safety
harness and lifeline in accordance with paragraph (J) of rule
4123:1-3-03
of the Administrative Code. The attachment point of the lifeline to the
structure shall be appropriately changed as the work progresses.
(M) Boatswains' chairs.
(1) When constructed of wood the chair seat
shall be no less than twelve inches by twenty-four inches by one-inch
thickness, reinforced by cleats on the underside to prevent splitting. A chair
of the same size may be constructed of material of equal strength.
(2) Seat slings shall be of no less than
five-eighths-inch diameter, "First Grade" manila rope, or its equivalent, which
shall be reeved through the four seat holes so as to cross each other on the
underside of the seat.
(3) Seat
slings shall be of no less than three-eighths-inch wire rope when an employee
is conducting a heat-producing process, such as gas or
arc
welding.
(4) The employee shall be
protected by a safety belt or harness and lifeline in accordance with paragraph
(J) of rule
4123:1-3-03
of the Administrative Code. The attachment point of the lifeline to the
structure shall be appropriately changed as the work progresses.
(5) The tackle shall consist of correct size
ball bearing or bushed blocks and properly spliced five-eighths-inch diameter,
"First Grade" manila rope, or equivalent.
(6) The roofirons, hooks, or the object to
which the tackle is anchored, shall be securely installed. Tiebacks shall be
installed at right angles to the face of the building and securely fastened
when using wall hooks.
(N) Carpenters' bracket scaffolds.
(1) The brackets shall consist of a
triangular wood frame no less than two inches by three inches in cross section,
or of metal of equivalent strength. Each member shall be properly fitted and
securely joined.
(2) Each bracket
shall be secured to the structure by a means which shall provide a factor of
safety of no less than four.
(3)
The brackets shall be spaced no more than eight feet apart.
(4) The platform shall consist of no less
than two two-inch by ten-inch "Scaffold Grade" planks extending no more than
twelve inches or less than six inches beyond each and support.
(O) Bricklayers' square scaffolds.
(1) Bricklayers' square scaffolds shall
conform to "Table 10-12" and the square shall not exceed five feet in width and
five feet in height.
(2) The
squares shall be reinforced on both sides of each corner with one-inch by
six-inch gusset pieces. They shall also have diagonal braces one inch by eight
inches on both sides running from center to center of each member, or other
means to secure equivalent strength and rigidity.
(3) The squares shall be set no more than
five feet apart for medium duty scaffolds, and no more than eight feet apart
for light duty scaffolds. Bracing, one inch by eight inches, extending from the
bottom of each square to the top of the next square, shall be provided on both
front and rear sides of the scaffold.
(4) Platform planks shall be no less than
two-inch by ten-inch "Scaffold Grade." The ends of the planks shall overlap the
bearers of the squares and each plank shall be supported by no less than three
squares.
(5) Bricklayers' square
scaffold shall not exceed three tiers in height and shall be so constructed and
arranged that one square shall rest directly above the other. The upper tiers
shall stand on a continuous row of planks laid across the next lower tier and
be nailed down or otherwise secured to prevent displacement.
(6) Scaffolds shall be level and plumb and
set upon a firm foundation.
Table 10-12. Minimum dimensions for bricklayers' square
scaffold members.
|
Members
|
Dimensions
|
|
Bearers or horizontal members
|
2 x 6 in.
|
|
Legs
|
2 x 6 in.
|
|
Braces at corners
|
1 x 6 in.
|
|
Braces diagonally from center frame
|
1 x 8 in.
|
(P) Foot scaffolds.
(1) Foot scaffolds shall not exceed eighteen
inches in height, measured from the level upon which the supports are
placed.
(2) Foot scaffolds imposed
on other scaffolds when supported on brick or tile, shall be limited to
eighteen inches in height and have a bearing surface of no less than ninety-six
square inches. Supports shall be no more than seven feet cent to
center.
(Q) Horse
scaffolds.
(1) Horse scaffolds shall not be
constructed or arranged more than two tiers in height.
(2) The members of the horses shall be no
less than those specified in "Table 10-13."
(3) Horses shall be spaced no more than five
feet for medium duty and no more than eight feet for light duty.
(4) When arranged in tiers, each horse shall
be placed directly over the horse in the tier below.
(5) On all scaffolds arranged in tiers, the
legs shall be nailed down or otherwise secured to the planks to prevent
displacement or thrust and each tier shall be substantially cross
braced.
(6) Defective or damaged
horses or parts shall not be used.
Table 10-13. Minimum dimensions for horse scaffold
members.
|
Members
|
Dimensions
|
|
Horizontal members or bearers
|
3 x 4 in.
|
|
Legs
|
1-1/4 x 4-1/2 in.
|
|
Longitudinal brace between legs
|
1 x 6 in.
|
|
Gusset brace at top of legs
|
1 x 8 in.
|
|
Half diagonal braces
|
1-1/4 x 4-1/2 in.
|
(R) Chimney, stack, or tank bracket
scaffolds.
(1) Minimum width.
The minimum width of platform shall be no less than eighteen
inches.
(2) Spacer blocks.
Spacer blocks, large enough to hold the suspending cable away
form the structure, shall be provided.
(3) Ascending and descending.
For ascending to and descending from a chimney, stack or tank
bracket scaffold, a scaling ladder or boatswain's chair shall be
provided.
(4) Platforms on
masonry chimneys or stacks.
Platforms supported on the rim of masonry chimneys or stacks
are prohibited.
(5) Inside
scaffolds.
In construction of chimneys or stacks where an inside scaffold
is being used, the working platform shall be no less than eighteen inches below
the top of the wall.
(6)
Guardrails.
Chimney, stack, or tank bracket scaffolds shall be provided
with standard guardrails, but no guardrail is required when safety belts or
harness with lifelines are provided.
(S) Needle beam scaffolds.
(1) Wood needle beams shall be no less than
four inches by six inches in size, with the greater dimensions placed in a
vertical direction. Metal beams or the equivalent, conforming to paragraph
(C)(2) of this rule may be used and shall not be altered or moved horizontally
while they are in use.
(2) Ropes or
hangers shall be provided for supports. The span between supports on the needle
beam shall not exceed ten feet for four-inch by six-inch timbers. Rope supports
shall be equivalent in strength to one-inch diameter "First Grade" manila
rope.
(3) The scaffold shall be
rigged so as to prevent the needle beam from rolling or becoming otherwise
displaced.
(4) The platform span
between the need beams shall not exceed eight feet when using two-inch
"Scaffold Grade" planks. For spans greater than eight feet, platforms shall be
constructed based on design requirements for the special span. The overhang of
each end of the platform planks shall be no less than six inches and no more
than twelve inches. Planks shall be secured against displacement.
(5) All unattached tools, bolts, and nuts
used on needle beam scaffolds shall be kept in suitable containers, properly
secured.
(6) One end of a needle
beam scaffold may be supported by a permanent structural member conforming to
paragraph (C)(2) of this rule.
(7)
Each employee working on a needle beam scaffold shall be protected by a safety
harness and lifeline in accordance
with paragraph (J) of rule
4123:1-3-03
of the Administrative Code.
(T) Interior hung scaffolds.
(1) An interior hung scaffold shall be hung
or suspended from a structure capable of providing a factor of safety of no
less than four.
(2) The suspending
wire or fiber rope shall be capable of supporting no less than six times the
maximum rated load.
(3) The
scaffold shall be designed to sustain a working load with a factor of safety of
no less than four.
(4) For wood
scaffolds, the following minimum "Scaffold Grade" material shall be used:
(a) Supporting bearers, two inches by ten
inches on edge;
(b) Planking, two
inches by ten inches, with maximum span of seven feet for heavy duty and ten
feet for light duty or medium duty.
(5) Steel tube and coupler members may be
used for such type scaffolds.
(U) Ladder jack scaffolds.
(1) All ladder jack scaffolds shall be
limited to light duty and shall not exceed a height of twenty feet above the
floor or ground.
(2) All ladders
used in connection with ladder jack scaffolds shall be heavy duty ladders.
Cleated ladder shall not be used for this purpose.
(3) The ladder jack shall be so designed and
constructed that it will bear on the side rails in addition to the ladder
rungs, or if bearing on rungs only, the bearing area shall be no less than ten
inches on each rung.
(4) Ladder
used in conjunction with ladder jacks shall be so placed, fastened, held, or
equipped with devices so as to prevent slipping.
(5) The platform shall be "Scaffold Grade,"
two-inch by ten-inch plank, or material of equal strength. Planks shall overlap
the bearing surface no less than twelve inches. The span between supports shall
not exceed eight feet. Platform width shall be no less than eighteen inches and
provide a factor of safety of no less than four.
(V) Window jack scaffolds.
(1) Window jack scaffolds shall be used only
for the purpose of working at the window opening through which the jack is
placed.
(2) Window jacks shall not
be used to support planks spaced between one window jack and another or for
other elements of scaffolding.
(3)
Window jack scaffolds shall be provided with standard guardrails unless safety
belts or harnesses with lifelines are attached and provided for the
employee.
(4) No more than one
employee shall be required to occupy a window jack scaffold.
(W) Float or ship scaffolds.
See appendix to this rule for examples of float or ship
scaffolds.
(1) No more than three
employees shall be required to occupy a float or ship scaffold.
(2) The platform shall be no less than three
feet wide and six feet long, made of three-quarter-inch plywood, equal to
"American Plywood Association Grade B-B, Group I, Exterior," or other
equivalent material.
(3) Under the
platform, there shall be two supporting bearers made from two-inch by
four-inch, or one-inch by ten-inch, rough, select lumber or better. Bearers
shall be free of knots or other flaws and project six inches beyond the
platform on both sides. The ends of the platform shall extend six inches beyond
the outer edges of the bearers. Each bearer shall be securely fastened to the
platform.
(4) An edging of wood no
less than three-fourths by one and one-half inches shall be placed around all
sides of the platform to prevent tools from rolling off.
(5) Supporting ropes shall be one-inch
diameter manila rope, or equivalent, providing a factor of safety of no less
than six. Rope connections shall be such that the platform cannot shift or
slip. Two ropes shall be used with each float, arranged so as to provide four
ends which are to be securely fastened to an overhead support. Each of the two
supporting ropes shall be securely fastened around one end of the bearer and
pass under the platform to the other end of the bearer where it shall be
securely fastened again, leaving sufficient rope at each end for the supporting
ties.
(X) Form scaffolds.
See appendix to this rule for examples of various types of form
scaffolds covered under this rule.
(1)
General requirements for all form scaffolds.
(a) All form scaffolds and their components
shall be capable of supporting without failure no less than four times the
maximum rated load.
(b) Maximum
permissible spans shall not exceed eight feet on centers for two-inch by
ten-inch "Scaffold Grade" planking. Scaffold planks shall be securely fastened
to the ledgers or of such length that they overlap the ledgers no less than six
inches. Unsupported projecting ends of scaffolding planks of all form scaffolds
shall be limited to a maximum overhang of twelve inches.
(2) Figure-four form scaffolds.
Figure-four form scaffolds are intended for light duty and
shall not be used to support loads exceeding twenty-five pounds per square foot
unless specifically designed for heavier loading. Frames shall be spaced no
more than eight feet on centers. (For minimum design criteria, see "Table
10-14").
Table 10-14. Minimum design criteria for figure-four form
scaffolds.
|
Members
|
Dimensions
|
|
Uprights
|
2 x 4 in. or 2 x 6 in.
|
|
Outrigger ledgers (two)
|
1 x 6 in.
|
|
Braces
|
1 x 6 in.
|
|
Guardrails
|
2 x 4 in.
|
|
Guardrail height
|
Approximately 42 in.
|
|
Intermediate guardrails
|
1 x 6 in.
|
|
Toeboards
|
4 in. (minimum)
|
|
Maximum length of ledgers
|
3 ft. 6 in. (unsupported)
|
|
Planking
|
2 x 10 in.
|
|
Upright spacing
|
8 ft. 0 in. (on centers)
|
(3)
Metal bracket form scaffolds.
(a) Metal
brackets or scaffold jacks which are an integral part of the form shall be
securely bolted or welded to the form. Folding type brackets shall be either
bolted or secured with a locking type pin when extended for use.
(b) "Clip-on" or "hook-over" brackets may be
used, provided the form walers are bolted to the form or secured by snap ties
or shea-bolt extending through the form and securely anchored.
(c) Metal brackets shall be spaced no more
than eight feet on centers.
(d)
Scaffold planks shall be either bolted to the metal brackets or of such length
that they overlap the brackets at each end by no less than six inches.
Unsupported projecting ends of scaffolding planks shall be limited to a maximum
overhang of twelve inches.
(e)
Metal bracket form scaffolds shall be equipped with standard guardrails and
toeboards, meeting the minimum dimensions shown in "Table 10-15."
Table 10-15. Minimum design criteria for metal bracket form
scaffolds.
|
Members
|
Dimensions
|
|
Uprights
|
2 x 4 in.
|
|
Guardrails
|
2 x 4 in.
|
|
Guardrail height
|
Approximately 42 in.
|
|
Intermediate guardrails
|
1 x 6 in.
|
|
Toeboards
|
4 in. (minimum)
|
|
Planking
|
2 x 9 in.
|
(4) Wooden bracket form scaffolds.
Wooden bracket form scaffolds shall be an integral part of the
form panel. The minimum design criteria set forth herein and in "Table 10-16"
cover scaffolding intended for light duty and shall not be used to support
loads exceeding twenty-five pounds per square foot, unless specifically
designed for heavier loading.
Table 10-16. Minimum design criteria for wooden bracket form
scaffolds.
|
Members
|
Dimensions
|
|
Uprights
|
2 x 4 in. or 2 x 6 in.
|
|
Support ledgers
|
2 x 6 in.
|
|
Maximum scaffold width
|
3 ft. 6 in.
|
|
Braces
|
1 x 6 in.
|
|
Guardrails
|
2 x 4 in.
|
|
Guardrail height
|
Approximately 42 in.
|
|
Intermediate guardrails
|
1 x 6 in.
|
|
Toeboards
|
4 in. (minimum)
|
|
Upright spacing
|
8 ft. 0 in. (on centers)
|
(Y) Pump jack scaffolds.
(1) Pump jack scaffolds shall:
(a) Not carry a working load exceeding five
hundred pounds; and
(b) Be capable
of supporting no less than four times the maximum rated load.
(c) The manufactured components shall not be
loaded in excess of the manufacturer's recommended limits.
(2) Each pump jack bracket shall have two
gripping mechanisms to prevent any failure or slippage.
(3) The platform bracket shall be fully
decked and the planking secured. Planking, or equivalent, shall conform with
paragraph (C)(7) of this rule.
(4)
Poles and bracing.
(a) When wood scaffold
planks are used as platforms, poles for pump jacks shall be spaced no more than
ten feet center to center. When fabricated platforms are used that fully comply
with all other provisions of this section, pole spacing may exceed ten feet
center to center.
(b) Poles shall
not exceed thirty feet in height.
(c) Poles shall be secured to the work
surface by rigid triangular bracing, or equivalent, at the bottom, top and
other points as necessary, to provide a maximum vertical spacing of no more
than ten feet between braces. Each brace shall be capable of supporting a
minimum of two hundred twenty-five pounds tension and compression.
(d) For the pump jack bracket to pass bracing
already installed, an extra brace shall be used approximately four feet above
the one to be passed until the original brace is reinstalled.
(e) All poles shall bear on mud sills or
other firm foundations.
(f) Pole
lumber shall be two-by-fours, of Douglas fir, or equivalent, straight-grained,
clear, free of cross-grain, shakes, large knots, and other defects which might
impair strength.
(g) When poles
are constructed of two continuous lengths, they shall be two-by-fours, spiked
together with the seam parallel to the bracket, and with ten-penny common
nails, no more than twelve inches center to center, staggered uniformly from
opposite outside edges.
(h) If
two-by-fours are spliced to make up the pole, the splices shall be so
constructed as to develop the full strength of the member.
(5) A ladder shall be provided for access to
the platform during use.
(6) No
more than two employees shall be required at any time to be on a pump jack
scaffold between any two supports.
(7) Pump jack scaffolds shall be provided
with standard guardrails, but no guardrail is required when safety
harnesses with lifelines are
provided for employees.
(8) When a
work bench is used at an approximate height of forty-two inches, the top
guardrail may be omitted in the space occupied by the work bench, if the work
bench is fully decked, the decking is secure, and is capable of withstanding
two hundred pounds pressure in any direction.
(9) Employees shall not be required to use a
work bench as a scaffold platform.
(Z) Stilts.
Stilts shall be equipped with "feet" of skid resistant
material. Means shall be provided to securely fasten the stilts to employee's
feet and legs. The floor in the work area shall be maintained free of debris
and other possible hazards.
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