Accessible Route Width, Pinch Points, and Passing Spaces (2010 ADA Standards 403.5)
36 in is the route width, and the three rules around it are what get missed. The 32 in people quote is NOT a width -- it is a pinch, allowed for 24 in of length at most and only where reduced segments are separated by full-width runs 48 in long, so a hall built at 32 in is not a hall with an exception. A 180 degree turn around an element narrower than 48 in needs 42 in approaching and 48 in AT the turn, so a compliant 36 in corridor stops complying the moment it doubles back around a narrow stub -- unless the turn itself is 60 in. And any route under 60 in owes passing spaces every 200 ft, which is nearly every corridor and the thing nobody draws.
Formula and source
clear width >= 36 in; the reduction exception permits 32 in minimum for 24 in of length maximum where reduced segments are separated by segments 48 in long minimum and 36 in wide minimum; a 180 degree turn around an element less than 48 in wide requires 42 in approaching, 48 in at the turn, and 42 in leaving, unless the turn is 60 in minimum; a route under 60 in wide requires passing spaces at intervals of 200 ft maximum, so the minimum count keeping every stretch within the interval is max(0, ceil(length / 200) - 1).
2010 ADA Standards for Accessible Design, 403.5.1, 403.5.2, and 403.5.3. A US federal standard in the public domain, quoted directly.
Audience
This tile is built for trades and the adjacent professions in the Carpentry and Construction group. The interactive calculator runs entirely in your browser. No account, no fee, no advertising, no tracking.
Related tools
Posture
Rough Logic answers the math question the working professional asks on the job. The site is a calm, fast, ad-free, account-free, ever-free reference. It does not interpret code. It does not replace the licensed professional. It does not store your inputs. The Authority Having Jurisdiction governs all installations and inspections.