Page:UK Traffic Signs Manual - Chapter 8 - Part 2- Traffic Safety Measures and Signs for Road Works and Temporary Situations) - Operations 2009.pdf/68

GENERAL VEHICLE ISSUES

In urban situations or where traffic speeds are low, for very short-duration stops (less than 15 minutes) the roof-mounted flashing amber beacons and vehicle markings may constitute sufficient warning to other road users of the obstruction caused by a works vehicle; see Section O8 and Part 1: Design, Section D3.31. However, when approach visibility is poor, traffic flows are heavy and/or traffic speeds are high, additional warning shall be given by the use of a tapered length of cones on the approach side (see Table A1.3 (Appendix 1) and advance road works signs.

On all-purpose roads, where a works vehicle is parked in advance of the works with the intention of providing some physical protection, a minimum clearance of 2 m should be provided when the speed limit is 30 mph or less. This clearance should be increased to 5 m when the speed limit is 40 mph or more. The longitudinal clearance will then be measured from that part of the vehicle facing oncoming traffic. The permissible reduction in signing when a works vehicle is in attendance is described in Section O3.19.

Most traffic regulation orders dealing with waiting restrictions on minor roads make exemptions for vehicles belonging to statutory undertakers, local authorities and contractors while carrying out road works; consequently these may wait despite the presence of waiting restrictions. In these circumstances, where the presence of parked vehicles is abnormal and provided the road works are wholly within the footway, no advance signs are required. The minimum guarding required, in addition to the barriers protecting the works, is a roof-mounted flashing amber beacon. If the road works are in the carriageway extra precautions will be needed.

During routine maintenance of street lighting equipment, overhead telecommunications and electricity works by undertakers, it is often necessary for a vehicle to stand on the carriageway. The vehicle will have a hoist system in order to raise operators and replacement equipment to, for example, lantern level. Nets should be provided around and under the bucket to catch any articles dropped by the operators.

The presence of stationary or slow-moving vehicles in live traffic lanes on high-speed roads should be minimised. Where temporary traffic management operations involve the encroachment of stationary or slow-moving vehicles into live traffic lanes on a dual carriageway, each such vehicle should:
 * be afforded impact protection;
 * be fitted with a light arrow sign;
 * be protected by advance signing – see also paragraph O3.6.3; and
 * take up a position in the centre of the lane to be blocked;

or otherwise the stationary or slow-moving vehicle should be protected by a vehicle complying with the above.

This does not apply to vehicles entering or leaving the works area, hard shoulder or verge.

On high-speed dual carriageway roads without hard shoulders, operations should be planned to identify safe taper positions which facilitate the provision of advance signing without the need for stationary or slow-moving works vehicles to encroach into live lanes when pre-placing, erecting or removing traffic management equipment. 66