Technical Booklet H Stairs Ramps Guarding and Protection from Impact·Page 38·4.18
Raised kerbs on ramps
Ramps with open sides must have a raised kerb of at least 100 mm high (except where it would obstruct normal use). The kerb must be visually distinct from the ramp surface and landings.
A ramp should have a raised kerb on any open side (except where it would obstruct normal use). The raised kerb should – (a) be not less than 100 mm high; and (b) be distinguishable, through suitable visual contrast, from that of the surface of the ramp and landings.
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