36 CFR Part 1191 ABA Accessibility Guidelines, Outdoor Developed Areas - Preamble

1016.5 Obstacles

This section contains technical requirements for obstacles on outdoor recreation access routes, passing spaces, and resting intervals. The vertical alignment of joints in concrete, asphalt, or board surfaces on outdoor recreation access routes can be obstacles. Natural features such as tree roots and rocks on outdoor recreation access routes also can be obstacles. Where an outdoor recreation access route is provided within a vehicular way, traffic calming devices can be obstacles. This section requires obstacles to not exceed 1/2 inch in height measured vertically to the highest point. Where the surface is other than concrete, asphalt, or boards, obstacles are permitted to not exceed 1 inch in height measured vertically to the highest point.

The frequency of obstacles and obstacles that cross the full width of outdoor recreation access routes can make travel difficult for individuals who use wheeled mobility devices. Where possible, obstacles that cross the full width of outdoor recreation access routes should be separated by 48 inches minimum so individuals who use wheeled mobility devices can cross the obstacle before confronting another obstacle.