Page:UK Traffic Signs Manual - Chapter 8 - Part 2- Traffic Safety Measures and Signs for Road Works and Temporary Situations) - Operations 2009.pdf/90



Single vehicle works are those works which involve a vehicle either standing for a short-duration or operating at low speed in the carriageway, normally on an urban or low speed road where a Mobile Lane Closure in accordance with Section O10 is inappropriate. The works vehicle used shall display a "keep left/right" sign to diagram 610 conspicuously on the rear or front of the vehicle as appropriate to show approaching drivers which side to pass, in accordance with regulation 15. The use of signs attached to the works vehicle must comply with regulation 14.

Vehicle-mounted "keep left/right" signs to diagram 610 shall be covered when the vehicle is travelling to and from the site. At no time must they be pointed directly up or down.

Single vehicle works should not be carried out on dual carriageway roads where the national speed limit applies, except for works such as gritting, salting and damping down of dust, which are undertaken at a controlled speed nearing that of normal road speed; see paragraph O8.2.1.

Single vehicle works should normally only be carried out on the near side lane of a carriageway, see also paragraph O8.1.19.

On roads where the speed limit is 40 mph or more, if practical and appropriate, and subject to risk assessment, consideration should be given to fitting a lorry-mounted crash cushion (LMCC) to the working vehicle and/or any escort vehicle that may be employed. It should be noted that LMCCs may be inappropriate on roads with poor alignment, and less than 5.5 m wide, as they may create an additional hazard to road users.

On roads where the speed limit is 40 mph or more, the working vehicle shall carry a sign to diagram 7403 on the rear. If an escort vehicle carrying a sign to diagram 7403 is provided, the sign on the works vehicle can be to either diagram 610 or 7403 but on single carriageway roads the use of the sign to diagram 610 on the works vehicle is the preferred option as this will help retain forward visibility past the works vehicle. The size of the sign to diagram 610 to be used is given in Table A1.2 of Appendix 1.

The standard light arrow sign (see Section O10.8) may be used to replace the sign to diagram 7403 on either vehicle. Note that the light arrow element of this sign shall not be used on two-way single carriageway roads.

An authorised small light arrow sign may be used on works vehicles as a substitute for a sign to diagram 610 and for the sign to diagram 7403. Details of which signs are authorised for use in this manner, and the limitations on their use as a substitute for the sign to diagram 7403, should be confirmed with the Overseeing Organisation. Where the traffic authority has carried out a risk assessment and determined that using the small light arrow sign on a road subject to a maximum speed limit above 40 mph will not compromise safety, they may apply for special authorisation to do so.

Work carried out using single vehicles standing or operating in the carriageway should be carried out only during periods of low risk.

Advance warning to traffic in each direction should be given by a "road works" sign to diagram 7001, a supplementary plate variant to diagram 7001.1 and a "road narrows" sign variant to diagram 517 with a "single file traffic" supplementary plate to diagram 518 (Plan SVW1). The distance between the signs should be sufficient to enable moving work to progress before the signs are moved and should not exceed 1 mile. Subject to a risk assessment, the supplementary plate to diagram 570 "For 1 mile" in Plan SVW1 may be replaced by a supplementary plate to diagram 7001.1 showing the type of mobile operation taking place and optionally "for" and a distance in the manner shown in working drawing P7001.1 may be included. The distance shown on plates 570 or 7001.1 may be varied. Repeater signs to diagram 7001 may be required if the road alignment is poor. 88