2013 California Standards for Accessible Design Pocket Guide

Advisory 11B-502.4 Floor or ground surfaces. Accessible parking spaces and access aisles are required to be level (maximum 1:48 slope) in all directions to provide a surface for wheelchair transfer to and from vehicles.  The access aisle needs to be adjacent to, and the same required length as the accessible space it serves.  Where two parking stalls share the same access aisle, a full depth aisle is required; in diagonal parking, the geometric layout will require additional access aisle depth to satisfy the loading area for both of the adjacent parking stalls as indicated in Figure 11B-502.3.3.◼