Page:UK Traffic Signs Manual - Chapter 8 - Part 1 (Traffic Safety Measures and Signs for Road). Designs 2009.pdf/37

DESIGN CRITERIA within the taper. The lights have been authorised for use on the motorway and trunk road network. However, for use on other roads, the need for specific authorisation of these lights should be checked with the relevant Overseeing Organisation prior to their use.

Further guidance on the use of warning lights is given in Part 2: Operations, Section O4.7.

Rotating reflector delineators are mechanisms complying with regulation 56(6) which enable one or more amber reflectors, complying with diagram 560 or 561, to be displayed intermittently whilst rotating and constantly whilst static. They do not constitute warning lights to BS EN 12352:2006. They must always be mounted on top of traffic cones to diagram 7101.1. Rotating reflector delineators may be used only in conjunction with traffic cones delineating the outer edge of a safety zone where this runs parallel with the traffic lane. They must not be used in lead-in tapers.

It is essential that at all times all persons who use the highway should clearly see the lateral limits of the works and traffic lanes that they are required to use, from all directions of approach. This should be achieved by the use of some or all of the following: traffic cones, traffic cylinders, temporary white lines, temporary reflecting road studs, temporary barriers, and additionally warning lights must be used during the hours of darkness and in poor visibility, see Section D3.12.

The boundaries of all road works must be clearly delineated to indicate the limits of the carriageway and to protect the works and personnel. This should be done by means of traffic cones, cylinders and barriers, and prescribed signs in accordance with the Regulations. Warning lights must be used after dark and should be used at times of poor visibility. The aim should be to guide approaching vehicles gradually into a lane past the works. The devices used may be supplemented by temporary edge of carriageway markings. The overall appearance should be such that drivers can readily judge the limits of the lane.

Timber baulks, and non-approved proprietary barrier type systems, should not be used as a means of delineation of works areas on high-speed roads because their ability to control a fast-moving vehicle on impact is totally unpredictable. Their use on roads with a permanent speed limit of 30 mph with street lighting should be checked with the Highway Authority and is likely to be acceptable provided that:


 * they are securely fastened together and that each one is securely fastened to the ground
 * they are painted in alternate red and white bands, each approximately 600 mm wide.

The designer should discuss road closure options for any planned works with the police and the appropriate highway authorities early in the planning stage. For trunk roads the presumption is to maintain the existing route, see paragraph D3.15.12. However, where there is an agreed diversion route, or it is likely that a suitable diversion route can be found and agreed, the designer should include the diversion option in his risk assessment considerations.

Road diversions may be necessary in order to close a road or because of continuing congestion, and the need for temporary orders under Section 14 of the must be borne in mind. Sometimes such a diversion may be necessary only for traffic proceeding in one direction. 36