LIGHTWEIGHT BARRIERS
O4.11.14 Lightweight barriers may be used where there is no risk of pedestrians encountering the works or where there is a need to delineate the inner boundary of a safety zone (refer to paragraphs O3.2.11 to O3.2.13). All elements of lightweight barriers should be sufficiently stable to withstand wind buffeting from passing traffic and to prevent any part being blown into the live carriageway or presenting a hazard to traffic. Expanding barriers and barriers incorporating steel or plastic mesh and similar material are acceptable provided they are placed continuously. Specially adapted cord or tape systems may also be used, see paragraph O3.2.11. Lightweight barriers may be reflectorised.
VEHICLE SAFETY RESTRAINT BARRIERS
O4.11.15 In some cases it may be appropriate to provide a temporary vehicle safety barrier. It may be appropriate to provide traffic barriers in addition behind the safety barrier and outside its working width, or to mark the face of the safety barrier in accordance with diagram 7105 to aid conspicuity. The temporary safety barrier may take the form of a permanent type safety barrier erected temporarily or a purpose made temporary safety barrier made from concrete or steel, or other materials. Guidance on temporary and permanent safety barriers is given in TD 19 "Requirement for road restraint systems" (DMRB 2.2.8).
O4.11.16 Where a temporary vehicle restraint safety barrier is provided, the temporary road markings or studs used adjacent to the barrier should be to Detail E, F or H as specified in Table A1.5 (Appendix 1).
O4.12ROAD MARKINGS AND STUDS
O4.12.1 Road markings are used at road works principally to delineate the carriageway edge or to divide the carriageway into traffic lanes. When, during the course of road works operations, the road remains in use and dangerous conditions are likely to occur through the absence of road markings, temporary markings shall be provided.
O4.12.2 Unless traffic is to be confined to a single lane delineated by cones on each side, it is important that existing road markings, reflecting road studs and raised rib lines are removed or appropriately masked when they might be hazardous or give misleading information to drivers.
O4.12.3 Markings should be renewed or relaid as soon as possible after resurfacing or on the completion of road works which may have interfered with them. Where it is not possible to restore them immediately in permanent materials, a temporary marking should be used, particularly at sites such as road junctions where the absence of the marking is likely to give rise to dangerous conditions.
O4.12.4 Where it is not possible to provide temporary road markings drivers should be informed of their absence by means of advance warning signs. On lengths of road where lane lines or centre of carriageway lines have been removed, the sign "NO ROAD MARKINGS FOR X MILES" to diagram 7012 should be used with the appropriate distance inserted. At junctions where all, or any part, of the "STOP" or "GIVE WAY" markings have been removed and temporary markings cannot be provided, the sign variant “NO STOP MARKINGS” or "NO GIVE WAY MARKINGS" to diagram 7012 should be placed at or near the junction preferably about 5-10 m from the edge of the main road carriageway.
O4.12.5 It is important to remove any lengths of road markings which are in conflict with temporary traffic requirements, e.g. when vehicles would otherwise have to pass over raised rib lines at changeover and crossover positions or chevron markings at junctions, or when two or more parallel lanes of traffic are changing lanes. However, raised rib and other lane markings may be left in situ where they match with the temporary lane markings. There should be no need to remove or cover the lane markings at a changeover position when only one lane is being switched.
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