What makes a compartment ambulatory accessible
The ambulatory accessible compartment is the narrow stall with a grab bar on each side. Section 604.8.2.1 sets the width between 35 and 37 in., a maximum as well as a minimum, and the depth at 60 in. minimum. The width keeps a bar within reach on both sides of a person standing or sitting at the water closet.
It is an additional compartment, not a substitute for the wheelchair accessible one. Section 213.3.1 requires the wheelchair accessible compartment wherever compartments are provided, and adds the ambulatory compartment where six or more compartments are provided, or where urinals and water closets add up to six or more fixtures.
Measuring width, depth, and the water closet
Measure width between the compartment-side faces of the two side walls or partitions, and depth from the rear wall to the front partition. A stall that measures 38 in. between the panels fails the 37 in. maximum as surely as a 34 in. stall fails the minimum, so hold the partition layout to the range, not to the nearest standard panel size.
Section 604.2 places the water closet centerline 17 in. minimum and 19 in. maximum from the side wall or partition in this compartment, a step out from the 16 to 18 in. used elsewhere. With a 35 to 37 in. width, the fixture lands close to the middle. Because the compartment has no open side, 604.6 drops its rule that the flush control sit on the open side of the water closet.
Doors and hardware
Section 604.8.2.2 requires a self-closing door with a pull on both sides near the latch, and the door may not swing into the minimum required compartment area. On a compartment built to the minimum, that means an out-swinging door. Where the approach is to the latch side, keep 42 in. minimum between the door side of the compartment and any obstruction.
The opening itself follows Section 404: 32 in. clear minimum, measured between the face of the door and the stop with the door open 90 degrees (404.2.3), and a latch, lock, and pulls mounted 34 to 48 in. above the finish floor that work with one hand and without tight grasping, pinching, or twisting (404.2.7).
Grab bars on both walls
Section 604.8.2.3 requires a side wall grab bar on each side, each built to 604.5.1: 42 in. long minimum, starting 12 in. maximum from the rear wall and extending 54 in. minimum from it. Both bars mount horizontally with the top of the gripping surface 33 to 36 in. above the finish floor, or 18 to 27 in. at water closets for children's use (609.4).
Section 609.3 sets the spacing: 1½ in. between the wall and the bar, 1½ in. minimum to anything projecting below the bar or past its ends, and 12 in. minimum to anything above it. A dispenser tucked under one of the bars needs that 1½ in.
Section 609.8 requires the bar, its fasteners, the mounting device, and the supporting structure to take a 250 pound force at any point. When a side of the compartment is a partition rather than a wall, the bar still needs backing that carries that load, so specify partition panels prepared for grab bar mounting on both sides.
