(C) Ladders.
(1) Construction.
All ladders shall
will be substantially constructed of wood, metal
or other equivalent material. Ladders must
have to be able to support at least four times
the maximum intended load, except extra-heavy-duty type 1A metal or plastic
ladders, which must
have to be able to sustain 3.3 times the maximum
intended load.
(a) Side rails.
(i) Wood.
All wood parts shall
will be free from sharp edges and splinters;
sound and free from shake, wane, compression failures, decay, or other
irregularities. Low density wood shall not
cannot be used.
(ii) Metal.
Metal side rails shall
will be parallel or shall
will vary
uniformly in separation along the length (tapered) of the ladder or
shall
will
flare at the base. The design of the side rails shall be such that the ladder
will conform to the specific safety requirements
specifications of this code.
(b) Rungs, steps or treads.
(i) Wood.
Wood rungs, steps or treads shall
will be sound
material free from knots, shakes, cross grain, large checks or decay. All
rungs, steps or treads shall
will have a uniform spacing not less than ten
inches and not more than fourteen inches as measured between the centerlines of
the rungs, cleats, and steps.
(ii) Metal.
Metal rungs, steps or treads shall
will have a
uniform spacing not less than ten inches and not more than fourteen inches as
measured between the centerlines of the rungs, cleats, and steps. Metal rungs,
steps or treads to side rail connections shall
will be so
constructed as to conform to the factor of safety specified in paragraph (C)(1)
of this rule.
(2) Portable ladders.
(a) Metal rungs, steps or treads.
All metal rungs, steps or treads shall
will be
corrugated, knurled, dimpled, or coated with skid-resistant material.
(b) Safety shoes, spikes or spurs.
(i) All portable ladders
shall
will be
equipped with safety shoes, metal spikes or spurs. Safety shoes
shall
will be
surfaced with cork, rubber or other material with equivalent coefficient of
friction.
(ii) The
requirement
specifications in paragraph 2(b)(i)
does
of this rule
do not apply to step ladders, lashed ladders or hook ladders.
(c) Hook ladders.
Ladders designed for use by hooking shall
will be
equipped with two or more substantial metal hooks at the top of the
ladder.
(d) Portable metal
or conductive ladders.
Portable metal or conductive ladders shall not
cannot be
used near energized conductors or equipment except as may be necessary in
specialized work, such as in high voltage substations where non-conductive
ladders might present a greater hazard than conductive ladders. Conductive or
metal ladders shall
will be prominently marked as "Conductive."
(3) Extension ladders.
(a) Automatic locks.
Extension ladders shall
will be equipped with two automatic locks of
malleable iron or equivalent material attached to the side rails of the upper
extension and of such construction as to make the extension ladder equal in
strength to a ladder constructed of continuous side rails.
(b) Where a single rung support holds an
entire rung of the upper extension and the support is attached to both side
rails of the lower section, two automatic locks
shall
are not
be required.
(4) Step ladders.
(a) Height.
Step ladders shall not
cannot exceed twenty feet in length.
(b) Spreader.
A metal spreader shall
will be provided on step ladders to securely hold
the front and back sections in open position.
(5) Sectional ladders.
When sectional ladders are used they shall
will conform to
the following:
(a) Length.
Sectional ladders shall not
cannot exceed sixty feet in extended length.
(b) Connection joint.
(i) Adjacent sections
shall
will be
jointed by means of a groove in the bottom end of each rail of the upper of the
two sections setting firmly over extensions outside the side rails, of the
topmost rung of the next lower section and, at the same time, a groove in the
top end of each rail of the lower of the two sections setting firmly over the
bottom rung, inside the side rails, of the section next above.
(ii) The distance between the two rungs
(topmost rung of one section, bottom rung of the section next above) mentioned
in paragraph (C)(5)(b)(i) of this rule
shall
not
cannot be less than one
foot.
(iii) The fit between rail
grooves and rungs mentioned in paragraph (C)(5)(b)(i) of this rule
shall
will be
such as to provide a good fit without binding or unnecessary play.
(iv) The grooved ends of the sections
shall
will be
reinforced with a metal plate of not less than eighteen-gauge (manufacturing
standard) material properly secured thereto, and a rivet adjacent to the
groove, extending through the depth of the rail, or the equivalent
thereof.
(c) Structural
dimensions and
requirements
design specifications.
(i) The minimum dressed cross section and
distance between side rails of wood
shall
will be in accordance with Table 3-1 as follows:
|
Number of Sections
|
Thickness (inches)
|
Side Rails Cross Section Depth (inches)
|
Distance Base (inches)
|
|
Up to & including 4 sections
|
1-1/8
|
2-3/4
|
13
|
|
Over 4 sections, up to & including 6
sections
|
1-1/8
|
3-1/8
|
20
|
(ii) If
the length exceeds six feet, the side rail cross sections
shall
will be
correspondingly increased.
(6) Fixed ladders.
All fixed ladders more than twenty-four feet in length
shall
will be
equipped with a personal fall arrest system, ladder safety system, cage, or
well. This requirement
These design specifications do
does not apply to chimney ladders.
(a) Landing platforms.
(i) One section fixed ladders equipped with a
fall arrest system or ladder safety system
must
will have rest
platforms provided at maximum intervals of one hundred fifty feet.
(ii) Fixed ladders equipped with a cage or
well
must
will have offset landing platforms at maximum
intervals of fifty feet.
(iii) The
step-across distance for through ladders
must
not
cannot be less than seven inches and
not more than twelve inches to the nearest edge of the structure, building or
equipment accessed from the ladder.
(iv) For side-step ladders, the step across
distance
shall
will be not less than fifteen inches and not more than
twenty inches to the access points of the platform edge.
(v) All landing platforms
shall
will be
equipped with standard guard railings and toeboards, so arranged as to give
safe access to the ladder. Platforms
shall
will be no less than twenty-four inches in width
and thirty inches in length.
(vi)
One rung of any section of ladder
shall
will be located at the level of the landing
laterally served by the ladder. Where access to the landing is through the
ladder, the same rung spacing as used on the ladder
shall
will be used
from the landing platform to the first rung below the landing.
(b) Ladder extensions.
(i) The side rails of through or side-step
ladder extensions
shall
will extend three and one-half feet above the top
of the access level or landing platform served by the ladder.
(See figure 3-1)
(ii) For through ladder extensions, the rungs
shall
will be
omitted from the extension and the side rails are flared to provide not less
than twenty-four inches and not more than thirty inches of clearance. When a
ladder safety system is provided, the maximum clearance between side rails of
the extension
must not
cannot exceed thirty-six inches.
(iii) For side-step or offset fixed ladder
sections at landings, the side rails and rungs
must
will be
continuous in the extension (See figure 3-1)
Click to
view image
Click to
view image
Figure 3-1
(c) Grab bars.
Grab bars shall
will be spaced by a continuation of the rung
spacing when they are located in the horizontal position. Vertical grab bars
shall
will
have the same spacing as the ladder side rails. Grab bars' diameters
shall
will be
the equivalent of the round-rung diameters.
(d) Ladder safety devices.
Ladder safety devices may be used on ladders in lieu of cage
protection. No landing platform is required
needed in these cases. All ladder safety devices
such as those that incorporate life belts, friction brakes, and sliding
attachments shall
will meet the design requirements
specifications of the ladder which they serve.
(e) Counterweighted hatch covers.
Where counterweighted hatch covers are provided they
shall
will
open a minimum of seventy degrees from the horizontal. The distance from
centerline of rungs or cleats to the edge of the hatch opening on the climbing
side shall
will be not less than twenty-four inches from offset
wells or thirty inches for straight wells. There shall
will be no
protruding potential hazards within thirty inches of the centerline of rungs or
cleats; when unavoidable obstructions are encountered, the minimum clearance at
the obstruction may be reduced to twenty-four inches, provided deflector plates
are installed at an angle of sixty degrees from the horizontal (See figure
3-2).
Click to
view image
Figure 3-2
(f) Pitch of fixed ladders.
(i) The pitch of fixed ladders
shall
will
come in the range of seventy-five degrees and ninety degrees with the
horizontal. (See figure 3-3).
Click to
view image
Figure 3-3
(ii) Fixed ladders within the pitch range of
sixty to seventy-five degrees with the horizontal are permitted only where it
is found necessary to meet conditions of installation. Pitch ranges less than
sixty degrees with horizontal are
prohibited
not
permitted.
(iii) Ladders
having a pitch in excess of ninety degrees with the horizontal are
prohibited
not
permitted.
(g)
Manhole steps and ladders.
(i) Entrance into a
manhole
shall
will be by steps that are cast or mortared into the
walls of riser or conical top sections or by portable ladder. Portable ladders
shall
will
conform to the
requirements
specifications of paragraphs (C)(1) and (C)(2) of
this rule.
(ii) Manhole steps that
are cast or mortared into the walls of riser or conical top sections
shall
will
meet the following
requirements
specifications:
(a) Steps, appurtenances and fastenings
shall
will be
capable of supporting the maximum intended load.
(b) The distance between rungs, cleats, and
steps
shall not
cannot exceed sixteen inches and
shall
will be
uniform throughout the length of the ladder. Rungs on an individual rung ladder
shall
will be
so designed that the foot cannot slide off the end.
(c) When dissimilar types of materials are
used in the steps, appurtenances and fastenings, the materials
shall
will be
treated to prevent deleterious effects.
(d) The portion of the step projecting into
the riser or cone opening
shall
will be free of any hazardous sharp edges, burrs,
or projections.
(e) Ferrous metal
steps not painted or treated to resist corrosion
shall
will have a
minimum cross-sectional dimension of one inch.
(f) The minimum clear step width
shall
will be
ten inches.
(g) The step
shall
will
have a minimum perpendicular distance between the centerline of the manhole
step to the nearest permanent object in back of the step of at least four and
one-half inches.
(h) Rungs and cleats.
(i) All rungs
shall
will have a
minimum diameter of three-fourths inch for metal ladders or material of
equivalent strength, and minimum diameter of one and one-eighth inches for wood
ladders.
(ii) The distance between
rungs, cleats, and steps
shall
will
not be
spaced not less than ten inches and not more than fourteen inches and shall be
uniform throughout the length of the ladder.
(iii) The minimum clear length of rungs or
cleats
shall
will be sixteen inches.
(iv) Rungs, cleats, and steps
shall
will be
free of splinters, sharp edges, burrs, or projections which may be a
hazard.
(v) The rungs of an
individual-rung ladder
shall
will be designed so that the foot cannot slide
off the end. A suggested design is shown in figure 3-4 of this rule.
Click to
view image
Figure 3-4
(i) Fastenings.
Fastenings shall
will be an integral part of fixed ladder
design.
(j) Ladder cage.
A ladder cage which encircles the climbing space and is
securely fastened to the side rails of the fixed ladder or to the structure
shall
will be
provided.
(i) Size of cage.
The cage shall
will not extend less than twenty-seven or more
than twenty- eight inches from the centerline of the rungs of the ladder and
shall
will
not be less than twenty-seven inches in width. Vertical bars
shall
will be
at a minimum spacing of forty degrees around the circumference of the cage.
This will give a maximum spacing of approximately nine and one-half inches,
center to center. The inside of the cage shall
will be clear
of projections.
(ii) Top of
cage.
The top of the cage shall
will extend a minimum of forty-two inches above
the top of the landing.
(iii) Bottom of cage.
The bottom of the cage shall
will extend
down the ladder to a point not less than seven nor more than eight feet above
the base of the ladder, with bottom flared not less than four inches, or the
portion of the cage opposite the ladder shall
will be carried
to the base. (See figure 3-5.)
Click to
view image
Figure 3-5
(k) Ladder well.
(i) If a ladder well is provided, it
shall
will
permanently and completely enclose the climbing space and the ladder
shall
will be
securely fastened to the walls of the well.
(ii) Minimum clearance.
Ladder wells shall
will have a minimum clear width of fifteen inches
measured each way from the center-line of the ladder. Smooth-walled wells
shall
will be
a minimum of twenty-seven inches and not more
than thirty inches from the centerline of the rungs, steps or treads to the
well wall on the climbing side of the ladder. Where obstructions on the
climbing side of the ladder exist, there shall
will be a
minimum clearance of thirty inches from the centerline of the rungs, steps or
treads.
(7) Trolley and side-rolling ladders.
(a) Length.
Trolley ladders and side-rolling ladders longer than twenty
feet shall
will
not be provided.
(b)
Width.
The width between the side rails, inside to inside,
shall
will be
not less than twelve inches.
(c) Step attachment.
Flat steps shall
will be inset in the side rails one-eighth inch
and secured with not less than two 6-d nails at each end, or the equivalent
thereof. They shall
will be reinforced with angle braces or a
three-sixteenths-inch steel rod.
(d) Locking device.
Locking devices shall
will be provided on all trolley ladders.
(e) Tracks.
(i) Tracks
shall
will be wood or
metal (excluding cast iron) or a combination of these materials.
(ii) Tracks for the top end of ladders
shall
will be
fastened securely and
shall be so
constructed that the wheels will not jump the track.
(iii) Tracks for side-rolling ladders
shall
will be
supported by metal or wood brackets securely screwed or bolted to shelving or
other permanent structure at intervals of not more than three feet.
(f) Wheel carriages.
(i) The wheel carriage
shall
will be
so designed that a loose or broken wheel will not allow the ladder to drop or
become detached from the track.
(ii) The wheel carriage for the bottom of the
ladder
shall
will be securely fastened to the bottom of the
ladder.
(iii) The wheels at the
upper end of the ladder
shall
will have a minimum wheelbase of eight
inches.
(8)
Trestle and extension trestle ladders.
(a) The
width between the side rails at the base of the trestle ladder and base
sections of the extension trestle ladder
shall
will be not
less than twenty-one inches for all ladders and sections up to and including
six feet. Longer lengths
shall
will be increased at least one inch for each
additional foot of length. The width between the side rails of the extension
sections of the trestle ladder
shall
will be not less than twelve inches.
(b) The tops of the side rails of the trestle
ladder and of the base section of the extension trestle ladder
shall
will be
beveled, or of equivalent construction and
shall
will be
provided further with a metal hinge to prevent spreading.
(c) A metal spreader or locking device to
hold the front and back sections in an open position, and to hold the extension
section securely in the elevated position
shall
will be a
component of all extension trestle ladders and all trestle ladders over twelve
feet in length.
(d) Rungs
shall
will be
parallel and level. On the trestle ladder, or on the base sections of the
extension trestle ladder, rungs
shall
will be spaced not less than eight inches or more
than eighteen inches apart; on the extension section of the extension trestle
ladder, rungs
shall
will be spaced not less than six inches or more than
twelve inches apart.
(e) General
specifications - trestle and extension trestle ladders.
(i) Trestle ladders or extension sections or
base sections of extension trestle ladders
shall
will be not
more than twenty feet in length.
(ii) The minimum distance between side rails
of the trestle or extension sections or base sections at the narrowest point
shall
will be
not less than twelve inches. The width spread
shall
will be not
less than one inch per foot of length of side rail.
(9) Platform stepladder.
(a) The minimum width between side rails at
the platform
shall
will not be less than fifteen inches.
(b) The back legs and side rails
shall
will
extend at least twenty-four inches above the platform and
shall
will be
connected with a top member to form a three-sided rail, or equivalent
construction
shall
will be provided.
(c) The wood parts of a combined wood and
metal platform functioning as a spreader
shall
will not be
depended upon to contribute to the spreading or locking action.
(E) Boatswains' chairs.
(1) When constructed of wood, the chair seat
shall
will 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
will be of no
less than five-eighths-inch diameter, first grade manila rope, or its
equivalent, which
shall
will be reeved through the four seat holes so as
to cross each other on the underside of the seat.
(3) Seat slings
shall
will 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
will be
protected by a safety harness and lifeline in accordance with paragraph (I)(6)
of rule
4123:1-5-17 of the
Administrative Code. The attachment point of the lifeline to the structure
shall
will be
appropriately changed as the work progresses.
(5) The tackle
shall
will consist of
correct size ball bearing or bushed blocks and properly spliced
five-eighths-inch diameter, first grade manila rope, or equivalent.
(6) The roof irons or hooks
shall
will be
of proper size and design, securely installed and anchored. Tiebacks of
three-quarters-inch manila rope, or its equivalent,
shall
will serve as
an additional means of anchorage, which
shall
will be
installed as nearly as possible at right angles to the face of the building and
shall
will be
securely fastened to a chimney.
(F) Swinging scaffolds.
(1) Swinging scaffold platforms
shall
will be
no less than twenty inches and no more than thirty-six inches wide overall. The
platform
shall
will be securely fastened to the hangers by U-bolts or
by other equivalent means.
(2) The
hangers of swinging scaffolds
shall
will be capable of sustaining four times the
rated load.
(3) When hoisting
machines are used on swinging scaffolds, machines
shall
will be of an
approved design.
(4) The roof irons
or hooks
shall
will be of proper size and design securely installed
and anchored. Tiebacks of three-quarters-inch manila rope, or the equivalent,
shall
will
serve as an additional means of anchorage, which
shall
will be
installed as nearly as possible at right angles to the face of the building and
shall
will be
secured to a structurally sound portion of the building.
(5) Swinging scaffolds
shall
will be
suspended by wire, synthetic fiber, or natural fiber ropes capable of
supporting no less than six times the rated load. All other components
shall
will be
capable of supporting no less than four times the rated load.
(6) Only treated or protected fiber rope or
its equivalent
shall
will be used for or near any work involving the
use of corrosive chemicals.
(7) The
sheaves of all blocks
shall
will fit the size and type of rope
used.
(8) No more than two
employees
shall be required
are allowed to be on a two-point suspension
scaffold designed for a working load of five hundred pounds. No more than three
employees
shall be required
are allowed to be on a two-point suspension
scaffold designed for a working load of seven hundred fifty pounds.
(9) The employer
shall
will provide an
approved safety harness and lifeline for each employee working on a swinging
scaffold in compliance with paragraph (I)(6) of rule
4123:1-5-17 of the
Administrative Code.
(10) When two
or more scaffolds are used they
shall
will not be bridged one to another unless they
are designed to be bridged, the bridge connections are articulated, and the
hoists are properly sized. If bridges are not used, passage may be made from
one platform to another only when the platforms are at the same height and are
abutting.
(11) Each swinging
scaffold
shall
will be securely fastened to the building or structure
at each work location to prevent it from swaying. Window cleaners' anchors
shall not
cannot be used for this purpose. Tie-in anchors
designed for the rated load of the scaffold may be used.
(12) The platform of every swinging scaffold
shall
will be
capable of sustaining four times the rated load.
(13) All swinging scaffolds
shall
will
have standard guardrails and toeboards on all unprotected sides of platforms
more than ten feet above the ground.
(14) The free ends of fall lines from
scaffolds
shall
will be guarded to prevent tangling or
snagging.
