2010 ADAS 610.3.1 Rectangular Seats
The rear edge of a rectangular seat shall be 2 1/2 inches maximum and the front edge 15 inches minimum and 16 inches maximum from the seat wall. The side edge of the seat shall be 1 1/2 inches maximum from the adjacent wall.
Citation according to 2010 ADAS. Check your state’s accessibility laws. Some states such as California, Georgia and Florida have additional requirements and standards.