Traffic Signs Manual/Chapter 5/2009/9

9SIGNAL CONTROLLED JUNCTIONS

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GENERAL

9.1 Effective marking of the approaches to signal controlled junctions is essential if the signals are to operate at their maximum efficiency. To achieve this:

(i) the Stop line (diagram 1001) should be sited as near as practicable to the intersection, consistent with driver and pedestrian needs. Drivers waiting at the Stop line must have an uninterrupted view of at least one signal,

(ii) lane lines should be arranged to secure the maximum use of available carriageway space consistent with adequate lane width, and

(iii) where lanes are dedicated to a particular turning movement, the appropriate lane destination arrows should be provided at the commencement of the lane, and repeated as necessary (see also paras 9.9 and 13.1 to 13.3).

9.2 Figure 9-1 shows the standard layout of the Stop lines, signals and pedestrian crossings at a signal controlled junction having a different number of lanes on each approach. It also shows a left turn lane governed by priority markings instead of being under direct signal control.

9.3 Figure 9-2 shows a typical arrangement of lane and centre of carriageway markings at a signal controlled junction where a six-lane road subject to a 40 mph speed limit meets a four-lane road subject to a 30 mph speed limit.

STOP LINES

9.4 These are described in section 3. The Stop line should be positioned a minimum of 1.5 m in advance of the near side primary signal, although 2.5 m should be used where practicable. The marking should be positioned at right angles to the centre line of the carriageway, even at skew junctions.

9.5 At difficult sites, Stop lines and near side primary signals need to be located sufficiently far back from the junction to enable long vehicles to turn into that road without being blocked by vehicles waiting at the Stop line. This will however reduce junction capacity and it may be necessary to consider prohibiting the turn.

9.6 Guidance on the use of advanced stop lines for cyclists will be found in paras 16.20 to 16.22.

LONGITUDINAL MARKINGS

9.7 On the immediate approach to the signals, the normal lane marking (diagram 1005 or 1005.1) and the centre of carriageway marking (diagram 1008 or 1008.1) should change to the warning line versions (diagram 1004 or 1004.1). Table 4-3 gives details of the size and minimum number of marks recommended.

9.8 Lane markings may be laid within the junction where some guidance to traffic would be helpful, although care should be taken that the meaning is clear to drivers on all approaches and there is no risk of giving the impression of a Stop or Give Way line to transverse movements. The arrow to diagram 1038.1 (see figure 13-4) may be used to indicate a route through a junction, or used in pairs to indicate that opposing right-turning traffic should pass near side to near side (see figure 13-5). Further details can be found in paras 13.7 and 13.8.

LANE DESTINATION MARKINGS

9.9 It is essential that drivers are made aware in good time of the correct lane to use at signalled junctions. Where lanes are indicated for left or right turn movements only, it is particularly important that early notice is given by the use of the appropriate lane arrow, repeated as necessary. If this is neglected, drivers are likely to become trapped in the wrong lane. A lane arrow should be used at the start of a newly formed lane, and at heavily-trafficked junctions the lane markings should be extended sufficiently far upstream to cope with peak flows. The use of lane

arrows and lane destination markings is described in paras 13.1 to 13.5, and para 13.6 indicates where traffic regulation orders are required.

LANE WIDTHS

9.10 With new junctions, entry lane widths should be between 3 and 3.65 m, unless there are specific reasons to justify the use of narrower or wider lane widths. Where an existing junction is being improved or modified and available road space is restricted, then the permitted lane widths for straight ahead entry lanes may be reduced to 2.5 m provided that the 85th percentile approach speed does not exceed 56 kph (35 mph) and the reduced width enables a necessary extra lane to be provided. In exceptional circumstances, lane widths may be reduced to 2.25 m where it is not intended to make provision for large goods vehicles.

9.11 In all cases the lane and centre line markings (both varied to the warning module) should meet the Stop line.

9.12 The number of lanes on the exit side of the junction should match the number of ahead lanes at the Stop line. If localised widening of an exit is necessary to achieve this, the subsequent reduction in the number of lanes should be carried out beyond the junction over a distance of at least 100 m for a single lane reduction. Deflection arrows to diagram 1014 may be used to warn of the impending loss. Normally, it should be the right hand lane that is lost, so that slower vehicles are not required to merge with faster-moving accelerating traffic. In order to maintain capacity at signalled junctions, it is important to keep the exits as well as the approaches clear of parked vehicles.

9.13 If a pedestrian crossing point is provided at a signalled junction, whether itself signalled or not, the Stop line should be placed a minimum of 1.5 m in advance of the left hand side primary signal post, which should be 0.5 m from the nearer row of studs (diagram 1055.1). See also paras 6.15 and 9.4. Although previous advice was to position the signal head 1 m in advance of the crossing studs, this is excessive where tactile paving is used. The tactile surface is intended to lead people to the push button box; a gap of 1 m between the edge of the tactile surface and the box is too great to ensure this.

9.14 The width of the crossing is dependent upon site conditions, but is normally in the range 2.4 to 5 m. Exceptional numbers of pedestrians may require the width to be increased to a maximum of 10 m. Dropped kerbs and tactile paving should be provided at all crossing points. Where pedestrian refuges are provided, the full width of the crossing should be maintained through the refuge as a dropped kerb or flush with the carriageway.

UNSIGNALLED VEHICLE MOVEMENTS

9.15 Where a left turn slip road is provided outside the control of the traffic signals, Give Way markings to diagram 1003, the warning triangle to diagram 1023 and the upright sign to diagram 602 should be used (see figure 9-1). If visibility is such that a Stop line would be justified, the left turn should be brought under signal control. A left turn slip lane should be separated from the other lanes by a traffic island. If no provision is made for pedestrians, they are likely to have difficulty in crossing an unsignalled slip road in an otherwise signalled junction.

This work has been mirrored or sourced from material provided on the UK Government website at https://www.gov.uk/government/publications/traffic-signs-manual, which states material is available under the terms of the Open Government License unless indicated otherwise. (Crown copyright acknowledged.)

This is NOT an official transcription, and should NOT be considered in any way a controlled copy of the work in question.

This document no longer necessarily represents current practice, as it relates to an earlier version of the regulations (TSGRD 2002 as amended at publication date) rather than the current TSRGD 2016 regulations. It should not be used for actual design or operational use without consulting a more recent edition.

This version was transcribed in May 2015, from a 2009 impression.