Page:UK Traffic Signs Manual - Chapter 4 - Warning Signs. 2013.pdf/10

 adverse weather conditions or other natural causes, the failure of street lighting or malfunction of or damage to other equipment used in connection with the road, or damage to the road itself. Direction 38 requires such signs to be removed as soon as the hazard has passed, and in any case within six months.

A sign prescribed in the Regulations must be used where the warning can be conveyed by such a sign. Otherwise it may be designed following the requirements specified in regulation 53. The back of a temporary sign must be grey, black or in a non-reflective metallic finish, as for almost all other signs (direction 42). The use of a yellow or other coloured back is unsightly, visually intrusive and unlawful. 9