yawn.
Just help out fs
Hump Dimensions and Location
Speed humps must be at right angles to the carriageway, be at least 900mm long, be less than 100 mm high and more than 25mm high and not have a vertical face exceeding 6 mm. Note that most speed humps in the UK are now constructed at 75 mm height due to grounding on higher ones, and there are other guidelines on their use and such measures as leading and trailing slopes which are given later, but these do not necessarily have the force of law. Road humps may be constructed under Zebra, Pelican and Puffin crossings, if centrally located under them. However they cannot be placed near bridge supports, or near tunnels or culverts beneath the road.