The size shape and style of all signs, including traffic cones, must comply with the TSRGD (TSR (NI) in Northern Ireland). In Wales and some areas of Scotland the signs should be bilingual. The standard of reflectorisation must be in accordance with the relevant current British or European standards. The whole of the sign faces must be reflectorised, except for any parts coloured black. The retroreflective sleeves of cones must be kept clean. Damaged sleeves or cones must not be used.
In Wales, reference should be made to The Traffic Signs (Welsh and English Language Provisions) Regulations and General Directions 1985. In exceptional cases, road safety or technical reasons may prevent fully bilingual signing. This might be the case on very narrow single carriageways or where the proximity of hedges or walls results in there being insufficient room for bilingual signs. In such circumstances, it is a reasonable mitigation to provide two separate signs (one English, one Welsh) but you should consult your supervisor, manager or other competent person first.
Regularly check that all signs, cones and barriers are clearly visible and kept clean. Where site or traffic conditions change, appropriate adjustments should be made to signing, lighting and guarding.
Caution: Consult your supervisor, manager or other competent person at times of poor visibility or bad weather conditions, as you may need to provide additional signs or suspend the work.
The lighting and reflectorisation of signs and any supplementary plates used with them must comply with the requirements of the TSRGD (TSR (NI) in Northern Ireland).