Washington Administrative Code › Title 51 - Enterprise Services, Department of (Building Code Council) › Chapter 51-52 - State Building Code adoption and amendment of the 2021 edition of the International Mechanical Code › Section 51-52-0306 - Section 306-Access and service space

Current through Register Vol. 24-14, July 15, 2024
306.5 Equipment and appliances on roofs or elevated
				structures.
Where equipment requiring access or appliances are located
				on an elevated structure or the roof of a building such that personnel will
				have to climb higher than 16 feet (4877 mm) above grade to access such
				equipment or appliances, an interior or exterior means of access shall be
				provided. Such access shall not require climbing over obstructions greater than
				30 inches (762 mm) in height or walking on roofs having a slope greater than 4
				units vertical in 12 units horizontal (33 percent slope). Such access shall not
				require the use of portable ladders. Where access involves climbing over
				parapet walls, the height shall be measured to the top of the parapet
				wall.
Permanent ladders installed to provide the required access
				shall comply with the following minimum design criteria:
1. The side railing shall extend above the
			 parapet or roof edge not less than 42 inches (1067 mm).
2. Ladders shall have rung spacing not to
			 exceed 12 inches (305 mm) on center. The uppermost rung shall be a maximum of
			 24 inches below the upper edge of the roof hatch, roof or parapet, as
			 applicable.
3. Ladders shall have a
			 toe spacing not less than 7 inches (178 mm) deep.
4. There shall be a minimum of 18 inches (457
			 mm) between rails.
5. Rungs shall
			 have a minimum 0.75-inch (19 mm) diameter and be capable of withstanding a
			 300-pound (136.1 kg) load.
6.
			 Ladders over 30 feet (9144 mm) in height shall be provided with offset sections
			 and landings capable of withstanding 100 pounds (488.2
			 kg/m2) per square foot. Landing dimensions shall be
			 not less than 18 inches and not less than the width of the ladder served. A
			 guardrail shall be provided on all open sides of the landing.
7. Climbing clearances. The distance from the
			 centerline of the rungs to the nearest permanent object on the climbing side of
			 the ladder shall be a minimum of 30 inches measured perpendicular to the rungs.
			 This distance shall be maintained from the point of ladder access to the bottom
			 of the roof hatch. A minimum clear width of 15 inches shall be provided on both
			 sides of the ladder measured from the midpoint of and parallel with the rungs
			 except where cages or wells are installed.
8. Landing required. The ladder shall be
			 provided with a clear and unobstructed bottom landing area having a minimum
			 dimension of 30 inches by 30 inches centered in front of the ladder.
9. Ladders shall be protected against
			 corrosion by approved means.
10.
			 Access to ladders shall be provided at all times.
Catwalks installed to provide the required access shall be not
				less than 24 inches (610 mm) wide and shall have railings as required for
				service platforms.
EXCEPTION:
This section shall not apply to Group R-3
						  occupancies.
306.6 Appliances above ceilings.
Appliances that
				are located above ceilings shall have access for inspection, service and repair
				without removing
permanent construction
. Appliances that are
				located above a ceiling shall be provided with access to the working space(s)
				by an opening not smaller than 22 inches by 22 inches (559 mm by 559 mm). All
				enclosure doors or hinged panels shall be capable of opening a minimum of 90
				degrees.
The appliance is not required to be removable or replaceable
				through the enclosure door, hinged panel, removable lay-in ceiling tile, or
				other removable covers. The appliance may be removed or replaced by removing
				the ceiling or wall assemblies adjacent to the appliance as long as they
are not permanent construction
.
EXCEPTIONS:
1. This section shall not apply to replacement
						  appliances installed in existing compartments and alcoves where the working
						  space clearances are in accordance with the appliance manufacturer's
						  installation instructions.
2. A smaller enclosure door, hinged panel, removable
						  lay-in ceiling tile, or other removable covers shall be permitted when allowed
						  by the appliance manufacturer's installation instructions and electrical access
						  is not required.
Statutory Authority:
				  RCW
				    19.27.031,
				  19.27.074 and
				  chapters
				  19.27 and
				  34.05 RCW. 13-04-053, §
				  51-52-0306, filed 2/1/13, effective 7/1/13. Statutory Authority:
				  RCW
				    19.27.190,
				  19.27.074,
				  19.27.031 and
				  chapters
				  19.27 and
				  34.05 RCW. 10-03-099, §
				  51-52-0306, filed 1/20/10, effective
				  7/1/10.