Page:Report of the Departmental Committee on Traffic Signs (1946).djvu/57

 while traffic proceeding straight ahead or turning right is held up, stop lines should not extend across the nearside inner lane, but should stop short at least 8 ft. from the nearside edge of the carriageway.

Stop lines at police or signal controlled junctions should be sited

(a) at right angles to the flow of traffic;

(b) sufficiently far back to leave adequate room for pedestrians and, where there are cycle tracks, cyclists, to cross. At authorised pedestrian crossings a stop line separate from the lines of studs 1s necessary;

(c) sufficiently far back to enable turning traffic to avoid without difficulty vehicles held up at the stop line;

(d) subject to compliance with the foregoing, as near to the intersection as possible.

Stop lines laid down in conjunction with “Halt at Major Road Ahead ” signs should be sited as close to the junction as possible so as to give, without danger to traffic on the major road, maximum visibility to traffic held up at the stop line.

Stop lines must always be continuous.

Examples of stop lines are shown in diagrams 119 and 120 of Appendix VI.

Longitudinal white lines at junctions

147. A continuous longitudinal white line should be laid along the centre line of a two-way carriageway on the approach to a junction. Where a stop line is provided the central longitudinal line should extend up to the stop line. Elsewhere it should be stopped sufficiently far back from the junction to permit turning traffic to negotiate the junction without crossing the continuous line. On the open road the length of the line should be 100 ft., but in built-up areas a shorter length, generally not less than 50 ft., may be adequate.

At controlled junctions where the carriageway is sufficiently wide, continuous white lines parallel to the central line and on the near side of it, may be provided to form traffic lanes in each of which traffic intending to proceed in a particular direction may take up position. These lanes should in no circumstances be less than 8 ft. wide and should preferably be 10 or 11 ft. wide. Where continuous filtering to the left is permitted, the line nearest to the edge of the carriageway may be continued beyond the stop line and curved to the left.

Examples of longitudinal white lines at junctions are shown in diagrams 119, 120 and 121 of Appendix VI.

White lines at horizontal and vertical curves

148. At horizontal and vertical curves where visibility between meeting vehicles is restricted, a continuous central white line should be laid down for such distances as may be necessary to warn road users of potential danger.

White lines at central refuges

149. Continuous white lines should also be laid down to guide traffic past central refuges or traffic islands in the carriageway. Diagram 122 of Appendix VI shows the layout recommended. On open roads the lines should extend 100 ft. in each direction from the obstruction, but in urban areas this distance may be reduced to 50 ft.

White lines defining traffic lanes

150. On roads outside congested urban areas, the division of the carriageway into traffic lanes by intermittent white lines assists the orderly movement of traffic and thus contributes to safety. These lines form a particularly valuable aid to driving at night and in fog.