• The Americans with Disabilities Act of 1990 was a landmark piece of legislation that clearly established rules for accommodating individuals with disabilities. The act was put into practice to limit discrimination of disabled individuals and improve transportation, public accommodations and telecommunications for the disabled. As a result of the law, ramps for wheelchairs are required in many buildings created after 1992.
  
  

Slope and Width

• A wheelchair ramp may have a maximum slope of 1:12, though many wheelchair users cannot handle a slope that high. For that reason, the slope of the wheelchair ramp is preferred to be between 1:16 and 1:20. The maximum rise for any run on a wheelchair ramp is 30 inches. Any higher of a rise, and wheelchair users might not be able to handle the incline. The width of a wheelchair ramp must be at least 36 inches.
  
  

Ramp Landing

• The landing of the ramp must be level, or it may cause wheelchair users to bottom out or tip backward when they attempt to board the ramp. The landing needs to be at least as wide as the ramp run that leads to it, and the length must be at least 60 inches so that it can fit a wheelchair. If there is a doorway at the base of a landing, the area in front of the door must be able to allow a door to open. This amount of space ranges from 18 inches to 54 inches depending on where the latch is and the direction the door opens.
  
  

Handrails

• Ramps that have a rise of more than 6 inches and that are longer than 72 inches must have handrails. Handrails can have a maximum height of 28 inches to the top of a gripping surface. The handrail and the wall must be at least 1 1/2 inches away from the wall. When handrails are not continuous, they must extend at least 12 inches beyond the top and bottom of the segment of ramp. Handrails should be rounded or returned smoothly at their edge.
  
  

Other Rules

• For ramps and landings with drop-offs, there must be a curb, railing or other protective surface to prevent users from slipping off the ramp. These curbs must be a minimum of 2 inches high. Outdoor ramps must be created in such a way that will not accumulate water on its walking surfaces. If children are the primary users of a building, there should be both adult and children handrails present. There should be at least 9 inches of clearance between the adult and child handrails.