In the US, the
Americans with Disabilities Act (ADA) requires a
slope of no more than 1:12 for wheelchairs and scooters for business and public use, which works out to of ramp for each of rise. For example, a rise requires a minimum of in length of ramp. Additionally, ramps can be as long as needed but ADA limits the longest single span of ramp, prior to a rest or turn platform, to . The UK's guidelines as recommended by the
Disability Discrimination Act 1995 and
Equality Act 2010 are a maximum of 1:12 for ramps (with exceptions for existing buildings) "Ramps should be as shallow as possible. The maximum permissible gradient is 1:12 [...], with the occasional exception in the case of short, steeper ramps when refitting existing buildings." In
Hong Kong, wheelchair ramps may not exceed a 1:12 slope, except in some situations under the Barrier Free Access (BFA) terms. In South Africa 1:12 is the maximum slope unless the difference in level is less than 400 mm, in which case it is 1:10. [SANS 10400-S SS2(a)]. In Australia, the
National Construction Code requires a wheelchair ramp to have a maximum incline of 1 in 8. This means that for every travelled horizontally, the ramp rises . The wheelchair ramp must also have a minimum width of . ==Vehicle ramps==