ADAAG Appendix: A4.6.3 Parking Spaces.
The increasing use of vans with side-mounted lifts or ramps...has necessitated some
revisions in specifications for parking spaces and adjacent access aisles. The typical
accessible parking space is 96 in (2440 mm) wide with an adjacent 60 in (1525 mm)
access aisle. However, this aisle does not permit lifts or ramps to be deployed and still
leave room for a person using a wheelchair or other mobility aid to exit the platform or
ramp...The “van accessible” parking space required by these guidelines provides a 96 in
(2440 mm) wide space with a 96 in (2440 mm) adjacent access aisle which is just wide
enough to maneuver and exit from a side-mounted lift. If a 96 in (2440 mm) access aisle
is placed between two spaces, two “van accessible” spaces are created. Alternatively, if
the wide access aisle is provided at the end of a row...it may be possible to provide the
wide access aisle without additional space...A sign is needed to alert van users to the
presence of the wider aisle, but the space is not intended to be restricted only to vans.[...]
An essential consideration for any design is having the access aisle level with the parking
space. Since a person with a disability, using a lift or ramp, must maneuver within the
access aisle, the aisle cannot include a ramp or sloped area. The access aisle must be
connected to an accessible route to the appropriate entrance to a building or facility. The
parking access aisle must either blend with the accessible route or have a curb ramp
complying with 4.7. Such a curb ramp opening must be located within the access aisle
boundaries, not within the parking space boundaries. Unfortunately, many facilities are
designed with a ramp that is blocked when any vehicle parks in the accessible space.
Also, the required dimensions of the access aisle cannot be restricted by planters, curbs,
or wheel stops.