before install all advanced equipment: first all basic knowledge and fundamental should be discussed.
- wheel chair allowance and reach range space.
- normal allowance and reach range space.
reference: ADA
in short the area that wheel chair can access with other help should be at least 91.5 cm (around 1 metre) and if the wheelchair user need to use wheelchair in normal activities area clearance should be at least 1.5 metre.
easy accessible reachable of objects will be 25 cm around the wheel chair. this will help a lot on design of universal access.
slope for ramp should be 4.76 degree or 1:12 or less