Guidance on the 2010 ADA Standards for Accessible Design

Sections 505.10.2 and 505.10.3 of the 2010 Standards require handrail extensions at both the top and bottom of a flight of stairs. The requirement in the 1991 Standards that handrails extend horizontally at least 12 inches beyond the width of one tread at the bottom of a stair was changed in the 2004 ADAAG by the Access Board in response to public comments. Existing horizontal handrail extensions that comply with 4.9.4(2) of the 1991 Standards should meet or exceed the requirements of the 2010 Standards.

Commenters noted that the 2010 Standards will require handrail gripping surfaces with a circular cross section to have an outside diameter of 2 inches, and that this requirement would impose a physical barrier to individuals with disabilities who need the handrail for stability and support while accessing stairs.

The requirement permits an outside diameter of 1 ¼ inches to 2 inches. This range allows flexibility in meeting the needs of individuals with disabilities and designers and architects. The Department is not aware of any data indicating that an outside diameter of 2 inches would pose any adverse impairment to use by individuals with disabilities.