Always have a qualified assistant when using a manual mobility device on a ramp.
Always follow manufacturer's instructions on your power chair or scooter.
Portable ramps used strictly for loading and unloading an unoccupied chair or scooter into or out of a vehicle, can utilize a greater slope, as much as 14.5°. Slopes greater than this are not recommended.
Below is an incline chart to help you determine exactly how much ramp is needed for your particular situation.
The American with Disabilities Act (ADA) specifies that public access and commercial locations have handicapped access ramps, with an incline not to exceed 4.8°; which equates to one foot of ramp for every one inch of rise. This is represented in a ratio of 1:12.
To calculate the needed amount of ramp using this ratio, simply measure the vertical rise in inches, and convert that number to feet. This is how many feet of ramp is needed. For example, 12 inches of rise would require 12 feet of ramp.
Non-commercial locations such as your home are not required to meet ADA guidelines. This means that a steeper incline is allowed, which equates to less total length of ramp. We recommend a ratio of 1:9; which is nine inches of ramp for every one inch of rise, or an incline of 7.2°. A practical example of this would be 12 inches of rise would require nine feet of ramp.
To calculate the needed amount of ramp using this ratio, simply measure the vertical rise in inches, multiply that number by .75; and convert that number to feet. 12 inches of rise times .75 = 9. Nine feet of ramp is needed.
For additional calculations, refer to the chart below:
