In the UK there are no actual regulations concerning the use of portable wheelchair ramps, only recommendations.

These recommendations suggest that the maximum gradient for a portable wheelchair ramp over 2m long should be no steeper than 1:12. When a portable ramp is between 1.5 and 2m the gradient can be steepened to 1:8 and when the ramp is below 1.5m a 1:6 gradient is permissable.

The above recommendations apply when powered chairs are in use or if assistance is at hand for manual wheelchair users.

The recommendations also say that a 50mm upstand should be on both sides of portable ramps in order to prevent the wheels going of the edges, and also that when above 2m in lengh the ramps should have optional handrails.