Current through Register Vol. 24-06, March 15, 2024
(1) Existing ski lift facilities and
structures must not be required to be retrofitted with standard construction
work platforms, walkways, stairs or guardrails on exterior surfaces when such
features would add significantly to snow loading considerations. When such
standard protective features are omitted, alternative personal protective
measures must be used where possible. Examples include, but are not limited to:
Safety belt and lanyard, ladder climbing safety devices, temporary work
platforms or scaffolds, temporary or removable handrails, guardrails, or
walkways.
(2) Snow removal.
(a) During the operating season, standard
guardrails which would interfere with snow removal may be omitted in areas
where it can be anticipated that frequent snow removal will be necessary to
maintain operability of ski lift apparatus. Examples could include, but are not
limited to, the motor house roof or loading and unloading areas.
(b) Personnel barricades, signs, or other
devices must be used to deflect traffic or warn personnel of existing fall
hazards.
(3) All ski
lift towers installed after the effective date of this standard must be
equipped with permanent ladders or steps which meet the following minimum
requirements:
(a) The minimum design live load
must be a single concentrated load of two hundred pounds.
(b) The number and position of additional
concentrated live load units of two hundred pounds each as determined from
anticipated usage of the ladder must be considered in the design.
(c) The live loads imposed by persons
occupying the ladder must be considered to be concentrated at such points as
will cause the maximum stress in the structural member being
considered.
(d) The weight of the
ladder and attached appurtenances together with the live load must be
considered in the design of rails and fastenings.
(e) All rungs must have a minimum diameter of
three-fourths inch.
(f) The
distance between rungs on steps must not exceed twelve inches and shall be
uniform throughout the ladder length. The top rung must be located at the level
of the landing or equipment served by the ladder.
(g) The minimum clear length of rungs or
steps must be sixteen inches on new installations.
(h) Rungs, cleats, and steps must be free of
sharp edges, burrs, or projections which may be a hazard.
(i) The rungs of an individual-rung ladder
must be so designed that the foot cannot slide off the end. (A suggested design
is shown in Figure D-1, at the end of this section.)
(j) Side rails which might be used as a
climbing aid must be of such cross sections as to afford adequate gripping
surface without sharp edges or burrs.
(k) Fastenings must be an integral part of
fixed ladder design.
(l) All
splices made by whatever means must meet design requirements as noted in (a) of
this subsection. All splices and connections must have smooth transition with
original members and with no sharp or extensive projections.
(m) Adequate means must be employed to
protect dissimilar metals from electrolytic action when such metals are
joined.
(n) All welding must be in
accordance with the "Code for Welding in Building Construction" (AWS
D1.0-1966).
(o) Protection from
deterioration. Metal ladders and appurtenances must be painted or otherwise
treated to resist corrosion and rusting when location demands.
(4) Installation and clearance.
(a) Pitch.
(i) The preferred pitch of fixed ladders is
between the range of seventy-five degrees and ninety degrees with the
horizontal (Figure D-4).
(ii)
Substandard pitch. Fixed ladders must be considered as substandard if they are
installed within the substandard pitch range of forty-five and seventy-five
degrees with the horizontal. Substandard fixed ladders are permitted only where
it is found necessary to meet conditions of installation. This substandard
pitch range is considered as a critical range to be avoided, if
possible.
(iii) Pitch greater than
ninety degrees. Ladders having a pitch in excess of ninety degrees with the
horizontal are prohibited.
(b) Clearances.
(i) The perpendicular distance from the
centerline of the rungs to the nearest permanent object on the climbing side of
the ladder must be thirty-six inches for a pitch of seventy-six degrees, and
thirty inches for a pitch of ninety degrees (Figure D-2), with minimum
clearances for intermediate pitches varying between these two limits in
proportion to the slope.
(ii) A
clear width of at least fifteen inches must be provided each way from the
centerline of the ladder in the climbing space.
(iii) The side rails of through or side-step
ladder extensions must extend three and one-half feet above parapets and
landings.
(A) For through ladder extensions,
the rungs must be omitted from the extension and must have not less than
eighteen nor more than twenty-four inches clearance between rails.
(B) For side-step or offset fixed ladder
sections, at landings, the side rails and rungs must be carried to the next
regular rung beyond or above the three and one-half feet minimum.
(iv) Grab bars must be spaced by a
continuation of the rung spacing when they are located in the horizontal
position. Vertical grab bars must have the same spacing as the ladder side
rails. Grab bar diameters must be the equivalent of the round-rung
diameters.
(v) Clearance in back of
ladder. The distance from the centerline of rungs, cleats, or steps to the
nearest permanent object in back of the ladder must be not less than seven
inches, except that when unavoidable obstructions are encountered, minimum
clearances as shown in Figure D-3 shall be provided.
(vi) Clearance in back of grab bar. The
distance from the centerline of the grab bar to the nearest permanent object in
back of the grab bars must be not less than four inches. Grab bars must not
protrude on the climbing side beyond the rungs of the ladder which they
serve.
(c) The
step-across distance from the nearest edge of a ladder to the nearest edge of
the equipment or structure must not be more than twelve inches, or less than
two and one-half inches. However, the step-across distance may be as much as
twenty inches provided:
(i) The climber is
wearing a safety belt and lanyard; and
(ii) The lanyard is attached to the tower
structure before the climber steps off the ladder.
(5) Ski lift towers are not
required to be equipped with ladder cages, platforms or landings.
(6) Maintenance and use.
(a) All ladders must be maintained in a safe
condition. All ladders must be inspected regularly, with the intervals between
inspections being determined by use and exposure.
(b) When ascending or descending, the climber
must face the ladder.
(c) Personnel
must not ascend or descend ladders while carrying tools or materials which
could interfere with the free use of both hands.
(7) Personnel must be provided with and must
use ladder safety devices or safety belts and lanyards whenever
feasible.
(8) Personnel must not
place mobile equipment or personal equipment such as skis, ski poles, or large
tools within the falling radius of the lift tower while climbing or working on
the lift tower.
(9) Ski lift towers
and terminals are not required to be equipped with sheave guards on the
haulrope wheels.
(10) Ski lift
towers are not required to be equipped with work platforms.
(11) Personnel must use personal protective
equipment such as a safety belt and lanyard in accordance with the requirements
of chapter 296-880 WAC, Unified safety standards for fall protection.
(12) When fixed ladders on towers do not
reach all the way down to the ground or snow level, a specifically designed and
constructed portable ladder must be used for access to and from the fixed
ladder. Portable ladders must be constructed and maintained to the following
requirements:
(a) The portable ladder must be
constructed in accordance with applicable provisions of subsection (3) of this
section.
(b) The portable ladder
must be constructed with a minimum of two attachment hooks near the top to be
utilized for securing the portable ladder onto the fixed ladder.
(c) The attachment hooks must be installed to
support the portable ladder near the fixed ladder side rails.
(d) Rungs or steps on the portable ladder
must be spaced to be identical with rungs or steps on the fixed ladder when the
portable ladder is attached for use. The design criteria must achieve a
horizontal plane relationship on the top (walking surface) portion of both
steps when overlapping is necessary.
(e) The portable ladder must be equipped with
a hold-out device near the bottom to assure clearance behind the steps as
required by subsection (4)(b)(v) of this section.
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FIGURE D-1
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FIGURE D-2
Minimum Ladder Clearance
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FIGURE D-3
Clearance for Unavoidable Obstruction at Rear of Fixed
Ladder.
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FIGURE D-4
Fixed Ladder Range
Statutory Authority: Chapter 49.17 RCW. 88-14-108 (Order
88-11), § 296-59-115, filed 7/6/88.