LAX APM ADA Coordinator Files (LINXS)
Section 11B-303 Changes in Level
Code excerpt regarding technical requirements for changes in level: general, vertical, beveled, ramps, and warning curbs.
11B-303 Changes in level
11B-303.1 General. Where changes in level are permitted in floor or ground surfaces, they shall comply with Section 11B-303.
Exceptions:
11B-303.2 Vertical. Changes in level of 1/4 inch (6.4 mm) high maximum shall be permitted to be vertical and without edge treatment.
11B-303.3 Beveled. Changes in level between 1/4 inch (6.4 mm) high minimum and 1/2 inch (12.7 mm) high maximum shall be beveled with a slope not steeper than 1:2.
Advisory 11B-303.3 Beveled. A change in level of 1/2 inch (13 mm) is permitted to be 1/4 inch (6.4 mm) vertical plus 1/4 inch (6.4 mm) beveled. However, in no case may the combined change in level exceed 1/2 inch (13 mm). Changes in level exceeding 1/2 inch (13 mm) must comply with Sections 11B-405 (Ramps) or 11B-406 (Curb Ramps).
11B-303.4 Ramps. Changes in level greater than 1/2 inch (12.7 mm) high shall be ramped, and shall comply with Section 11B-405 or 11B-406.
11B-303.5 Warning curbs. Abrupt changes in level exceeding 4 inches (102 m) in a vertical dimension between walks, sidewalks or other pedestrian ways and adjacent surfaces or features shall be identified by warning curbs at least 6 inches (152 mm) in height above the walk or sidewalk surface.
Exceptions:
This section requires a physically detectable barrier between changes in elevation greater than 4″ high where adjacent to pedestrian circulation elements.