8. Sign Backgrounds
1.69 Signs may lose their effectiveness because of their setting. Some of the smaller signs may fail to stand out against a background which is variegated and colourful and others may be overpowered by a stronger background.
1.70 Advertisements behind or near signs may prove distracting; flashing or brilliantly illuminated ones may cause road users to miss signs.
1.71 These points should be borne in mind both when siting new Traffic Signs and in the exercise of the control of advertisements under the planning regulations.
1.72 Where it is impossible to avoid a poor or distracting background it may be partially screened using a suitable backing board. Guidance on the correct design of backing boards can be found in the 2003 edition of Chapter 7 (paras 14.19 to 14.24).
9. Maintenance of Signs
1.73 Signs must at all times be maintained so as to preserve their original effectiveness and general condition. It is a waste of public money to provide signs and then to allow them to lose effectiveness by subsequent deterioration.
1.74 Signs become less effective not only when characters or colouring deteriorate, but also when dirty or damaged or displaced as a result of accidents or vandalism. Damaged or dirty signs discredit the highway authority and lessen road users' respect for the signs. A periodic inspection of signs should be made to ensure their early repair and/or replacement when necessary and after dark inspections should be made of illuminated or reflectorised signs.
1.75 Regular cleaning of all signs is essential. No firm advice can be given about frequency of cleaning since dirt deposition varies with the district, the climate, the time of the year and the position of the signs. Illuminated or reflectorised signs soon lose their effectiveness if damaged or dirty. Local conditions will also govern the methods of cleaning.
1.76 Further advice can be found in TD 25/01 in the Design Manual for Roads and Bridges, published by The Stationery Office.
