Washington Administrative Code › Title 296 - Labor and Industries, Department of › Chapter 296-155 - Safety standards for construction work › Part J - STAIRWAYS › Section 296-155-477 - Stairways

Current through Register Vol. 24-14, July 15, 2024
(1)
General.
The following requirements apply to all stairways as
				indicated:
(a) Stairways that will not be a
				permanent part of the structure on which construction work is being performed
				must have landings of not less than 30 inches (76 cm) in the direction of
				travel and extend at least 22 inches (56 cm) in width at every 12 feet (3.7 m)
				or less of vertical rise.
(b) You
				must install stairs between 30 degrees and 50 degrees from
				horizontal.
(c) In all buildings or
				structures two or more stories or 24 feet or more in height or depth, you must
				install suitable permanent or temporary stairways.
(d) You must provide stairways, ramps or
				ladders at all points where a break in elevation of 18 inches or more occurs in
				a frequently traveled passageway, entry or exit.
(e) You must provide a minimum of one
				stairway for access and exit for buildings and structures to 3 stories or 36
				feet; if more than 3 stories or 36 feet, you must provide two or more
				stairways. Where two stairways are provided and work is being performed in the
				stairways, you must maintain one clear for access between levels at all
				times.
(f)
Wood frame
				buildings.
(i) You must complete the
				stairway to a second or higher floor before studs are raised to support the
				next higher floor.
(ii) You must
				provide roof and attic work areas of all buildings with a safe means of access
				and egress, such as stairways, ramps or ladders.
(iii) You must nail cleats to studs to
				provide access to and egress from roof or other work areas.
(g)
Steel frame
				buildings.
Stairways must extend to the uppermost floor that has been
				planked or decked. Ladders may be used above that point.
(h)
Reinforced concrete or composite
				steel - Concrete buildings.
Stairways must extend to the lowermost floor
				upon which a complete vertical shoring system is in place. A minimum of two
				ladders at different locations for each floor may be used above this floor but
				not to exceed 3 floors.
(i) Riser
				height and tread depth must be uniform within each flight of stairs, including
				any foundation structure used as one or more treads of the stairs. Variations
				in riser height or tread depth must not be over 1/4-inch (0.6 cm) in any
				stairway system.
(j) Where doors or
				gates open directly on a stairway, you must provide a platform, and the swing
				of the door must not reduce the effective width of the platform to less than 20
				inches (51 cm).
(k) You must secure
				metal pan landings and metal pan treads, when used, in place before filling
				with concrete or other material.
(l) All parts of stairways must be free of
				hazardous projections, such as protruding nails.
(m) You must eliminate slippery conditions on
				stairways before the stairways are used to reach other levels.
(n) You are permitted to use alternating
				tread type stairs as long as they install, use, and maintain the stairs in
				accordance with manufacturer's recommendations and the following:
(i) The stair must be installed at an angle
				of 70 degrees or less.
(ii) The
				stair must be capable of withstanding a minimum uniform load of 100 pounds per
				square foot with a design factor of 1.7, and the treads must be capable of
				carrying a minimum concentrated load of 300 pounds at the center of any
				treadspan or exterior arc with a design factor of 1.7. If the stair is intended
				for greater loading, construction must allow for that loading.
(iii) The stair must be equipped with a
				handrail on each side to assist the user in climbing or descending.
(o) Due to space limitations, when
				a permanent stairway must be installed at an angle above 50 degrees, such an
				installation (commonly called an inclined or ship's ladder) must have treads,
				open risers and handrails on both sides.
(p) Where ladders are permitted for access
				under subsection (1) of this section, you must provide means for employee
				hoisting of tools and material, such as a well wheel and hoisting line or the
				equivalent, so employees will have both hands free for ascending and descending
				ladders.