Steel Plates may be required to bridge excavations in order to open the carriageway to traffic, e.g. during traffic sensitive periods, at night or at weekends. Their use must be authorised by a suitably qualified supervisor who will decide on the size and thickness of the plate to be used. The thickness will depend on the width of excavation to be spanned and the type of traffic expected to use them.*
The sides of any excavations must be suitably supported beneath the road plates and they must be rigidly secured to the road surface. Steel plates must be either sunk into the surface or suitable bitumastic material used to provide a ramp to the plate level. Where ramps are present, and there is a significant change in the road level, appropriate ramp warning signs should be in place.