2010 ADA Standards for Accessible Design Pocket Guide

1009.5.2 Transfer Space.

A transfer space of 60 inches (1525 mm) minimum by 60 inches (1525 mm) minimum with a slope not steeper than 1:48 shall be provided at the base of the transfer platform surface and shall be centered along a 24 inch (610 mm) minimum side of the transfer platform. The side of the transfer platform serving the transfer space shall be unobstructed.

Figure 1009.5.2 Clear Deck Space at Transfer Platform