Diagram 557.1 makes the road user aware they are travelling into a zone with road humps ahead. Used primarily to reduce vehicle speed in built up areas where excess speed can cause danger to pedestrians and increase the likelihood of collisions
Material: R2/RA2 reflective overlay on aluminium composite backing
12.1.1. Diagram 557.1 (S2‑2‑43, see Figure 12-1) is used to warn of the presence of a road hump or a series of humps. It must be accompanied by one of the plates shown. The plates must not be used alone. However, no signs are required to warn of humps in a 20 mph zone signed with traffic signs to diagram 674 (Highways (Road Humps) Regulations 1999). In Northern Ireland, refer to the Road Humps Regulations (Northern Ireland) 1999) and, in Scotland, the Road Humps (Scotland) Regulations 1998.