Ramps are essential for wheelchair users if elevators or lifts are not available to connect different levels Any part of an accessible route with a slope greater than 1:20 shall be considered a ramp.
Wheelchair Ramp Specs: Slope and Rise
Ramp slopes between 1:16 and 1:20 are preferred. The ability to manage an incline is related to both its slope and its length. Wheelchair users with disabilities affecting their arms or with low stamina have serious difficulty using inclines.
Most ambulatory people and most people who use wheelchairs can manage a slope of 1:16. Many people cannot manage a slope of 1:12 for 30 ft (9 m).
Therefore, to build according to wheelchair ramp specs, the least possible slope shall be used for any ramp. The maximum slope of a ramp in new construction shall be 1:12. The maximum rise for any run shall be 30 in (760 mm).
No alteration shall be undertaken which decreases or has the effect of decreasing accessibility or usability of a building or facility below the requirements for new construction at the time of alteration.
Wheelchair Ramp Specs: Clear Width
The minimum clear width of a ramp shall be 36 in (915 mm).
Wheelchair Ramp Specs: Landings
Level landings are essential toward maintaining an aggregate slope that complies with ADA guidelines. A ramp landing that is not level causes individuals using wheelchairs to tip backward or bottom out when the ramp is approached.
Therefore, ramps shall have level landings at bottom and top of each ramp and each ramp run. Landings shall have the following features
Wheelchair Ramp Specs: Handrails
The requirements for stair and ramp handrails in this guideline are for adults. When children are principal users in a building or facility (e.g. elementary schools), a second set of handrails at an appropriate height can assist them and aid in preventing accidents.
A maximum height of 28 inches measured to the top of the gripping surface from the ramp surface or stair nosing is recommended for handrails designed for children.
Sufficient vertical clearance between upper and lower handrails (9 inches minimum) should be provided to help prevent entrapment.
If a ramp run has a rise greater than 6 in (150 mm) or a horizontal projection greater than 72 in (1830 mm), then it shall have handrails on both sides.
Handrails are not required on curb ramps or adjacent to seating in assembly areas. Handrails shall have the following features:
Cross Slope and Surfaces
The cross slope of ramp surfaces shall be no greater than 1:50. Ramp surfaces shall comply with ADA standards for ground and floor surface.
Wheelchair Ramp Specs: Edge Protection
Ramps and landings with drop-offs shall have curbs, walls, railings, or projecting surfaces that prevent people from slipping off the ramp. Curbs shall be a minimum of 2 in (50 mm) high.
Ramp Specs: Outdoor Conditions
Outdoor ramps and their approaches shall be designed so that water will not accumulate on walking surfaces.