SiteScapes has confirmed, with the US Access Board, that there is currently NO ADA requirements as specified for outdoor benches.
ADA requirements were developed to enable people in wheelchairs to transfer to benches in situation-specific functions. People in wheelchairs typically do not transfer to benches outdoors. Instead, they will pull up next to or across from people sitting on benches or at picnic tables. Unless the bench is intended for a sauna, steam room, dressing room, locker room, holding cell or courtroom, it does not need to comply with section 903.
The only ADA guideline relating to OUTDOOR BENCHES can be found in "The Revised Draft Guidelines for Accessible Public Rights-of-Way" (http://www.access-board.gov/guidelines-and-standards/streets-sidewalks/public-rights-of-way/background/revised-draft-guidelines/chapter-3) under the section "Text of the Draft Guidelines," Chapter R3: Technical Provisions,R307.6.3.2:
"Where benches without tables are provided at a single location, at least 50 percent, but no fewer than one, shall have a seat height at the front edge of 43 cm (17in) minimum and 49cm (19in) maximum above the ground or floor space." (http://www.access-board.gov/guidelines-and-standards/streets-sidewalks/public-rights-of-way/background/revised-draft-guidelines/chapter-3)
Benches meeting these simple height guidelines are readily available from SiteScapes.
New requirements have been proposed and SiteScapes reccommends the following as a smart practice.
• Benches should have a seat height of 17" to 19" above ground or floor space.
• Clear "firm and stable" ground space adjacent to benches should be included and should be a minimum of 30" x 48".
• Seat backs should be provided that extend the full length of the seat.
• Benches should include armrests. For multiple benches, 1 of every 5 or no less than 2 should include armrests.