36 CFR Part 1190, Proposed Accessibility Guidelines for Pedestrian Facilities in the Public Right-of-Way: Notice of Proposed Rulemaking (NPRM)

Advisory R208.1 Where Required. On pedestrian access routes, detectable warning surfaces indicate the boundary between pedestrian and vehicular routes where there is a flush rather than a curbed connection. Detectable warning surfaces should not be provided at crossings of residential driveways since the pedestrian right-of-way continues across residential driveway aprons. However, where commercial driveways are provided with yield or stop control, detectable warning surfaces should be provided at the junction between the pedestrian route and the vehicular route. Where pedestrian at-grade rail crossings are located within a street or highway, detectable warning surfaces at the curb ramps or blended transitions make a second set of detectable warning surfaces at the rail crossing unnecessary.

Detectable warning surfaces are not intended to provide way finding for pedestrians who are blind or have low vision. Way finding can be made easier by:

• Sidewalks that provide a clear path free of street furniture;

• Visual contrast between walking and non-walking areas (e.g., planted borders);

• Route edges that are clear and detectable by cane;

• Direct pedestrian street crossings and curb ramps that are in-line with direction of travel;

• Small corner radiuses that permit pedestrian street crossings to be as short and direct as possible;

• Orthogonal intersections that facilitate navigation using parallel and perpendicular vehicle sound cues;

• and barriers where pedestrian travel or crossing is not permitted.