Diagram 556 marks an uneven road conditions that could cause danger when driving at normal speeds. Normally this sign should be a temporary measure until remedial work has been completed. However due to the road conditions throughout the UK this sign seems to be more of a permanent fixture across the nation!
Material: R2/RA2 reflective overlay on aluminium composite backing
11.1.1. The uneven road sign, diagram 556 (S13‑2‑5, see Figure 11-1), is used to warn of danger arising from longitudinal or transverse irregularities in the road surface which at the normal speed of traffic might seriously impair control of a vehicle. The use of this sign should generally be regarded as temporary, pending remedial work to the carriageway. It should be removed when the defect has been remedied. A plate to diagram 511 “REDUCE SPEED NOW” and also a plate “For” and a distance may be used with it. The uneven road sign should not be used at level crossings where the rail levels make the road uneven; diagram 782 is used for this purpose.