The Americans with Disabilities Act Accessibility Guidelines (ADAAG) defines an accessible route as "a continuous unobstructed path connecting all accessible elements and spaces of a building or facility." The ADA guidelines cover such details as elevators, ramps, floors, and corridors as well as exterior design elements like crosswalks and curbs.
Altogether, there are 10 factors to consider when creating an accessible route: location, width, passing space, headroom, surface textures, slope, changes in levels, doors, egress, and areas of rescue assistance. Here is a summary guide to each.
- Location: There must be at least one accessible route linking areas on a site to one another and to transportation, parking and public areas such as streets or sidewalks. This includes connecting buildings. There must also be accessible routes to each "dwelling" within a space. For example, it’s not enough for just the exterior facilities of an apartment building to be accessible; the guidelines apply to individual residences as well. It worth noting that the guidelines require that "to the maximum extent feasible, [accessible routes] coincide with the route for the general public." In other words, people with disabilities should not be relegated to a separate route where integration is possible.
- Width: The ADAAG specifies that accessible routes must be at least 36 inches wide. The one exception is doors, where the requirement is 32 inches for a door that requires entry and 20 inches for a space where users aren’t expected to move completely through the frame, such as a closet. For spaces in which the turning of a wheelchair is required, the guidelines include diagrams to better assist developers.
- Passing Space: For routes narrower than 60 inches, passing spaces must be provided at least every 200 feet. While the guidelines list a T junction of two corridors as an acceptable option, each passing space must be 60 inches by 60 inches.
- Headroom: There must be 80 inches of headroom in "circulation spaces" such as corridors and hallways. Where 80 inches is not possible, a barrier warning must be provided.
- Surface Textures: The guidelines mandate that all floor surfaces be "stable, firm, [and] slip-resistant." They also specify details about grate placement and carpet requirements, most of which relate to how the carpet is attached to prevent safety issues.
- Slope: This area of the guidelines separates what constitutes a ramp and also the maximum allowable cross slope (the side-to-side slope that enables drainage) of 1:50, or two percent.
- Changes in levels: The ADAAG requires than any change of level over 13 millimeters be accompanied by a curb ramp or elevator. A route cannot be deemed as accessible if it involves stairs, steps, or escalators.
- Doors: The guidelines covering various types of doors are extensive, accounting for clearances, thresholds, latches, power-assisted doors, and more. The force needed for opening a door is also defined, with the maximum set at five lbf (pound-force) for interior hinged doors and sliding or folding doors. Visit ADAAG 4.13 Doors for more information.
- Egress: Defined by the guidelines as “A continuous and unobstructed way of exit travel from any point in a building or facility to a public way,” all accessible routes must meet this requirement.
- Areas of Rescue Assistance: This last section identifies the requirements for emergency assistance areas, which must include at least two accessible areas that are at least 30 inches by 48 inches, along with other critical size, safety, communication, and identification guidelines. Visit ADAAG 4.3.11 Areas of Rescue Assistance for more information.