Traffic Signs Manual/Chapter 5/2009/21

21⁠TRAFFIC CALMING

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INTRODUCTION

21.1 This section is not intended to be a detailed description of traffic calming techniques, but a guide to the markings used with such schemes.

21.2 Advice on marking the following is given in the paragraphs indicated:

(i) speed limit roundels (paras 21.4 to 21.6),

(ii) road humps (paras 21.7 to 21.12),

(iii) speed cushions (paras 21.13 to 21.15),

(iv) thumps (para 21.16),

(v) humped crossings (para 21.17),

(vi) build-outs (paras 21.18 to 21.21),

(vii) chicanes and pinch points (paras 21.22 to 21.25), and

(viii) gateways (paras 21.26 to 21.28).

Guidance on the warning signs provided for road humps can be found in Chapter 4.

21.3 In 20 mph zones signed with diagram 674, road markings are not required on road humps, speed cushions or thumps; however they may be used if the traffic authority considers them appropriate. Hump markings are always required where a 20 mph speed limit is signed using diagram 670.

SPEED LIMIT ROUNDEL

21.4 An indication of the speed limit may be placed on the carriageway using the marking prescribed in diagram 1065. The marking is varied to show the speed limit in force and elongated in the direction of travel to compensate for the foreshortening effect (see figure 21-1). It must not be used in association with an advisory speed limit.

21.5 The marking may be used where a speed limit changes, or as a repeater in conjunction with upright signing. On roads where there is a 20 mph speed limit, elongated roundels may be used in conjunction with the vertical 20 mph repeaters. Neither signs nor road markings may be used as repeaters to indicate a 30 mph speed limit on roads with street lighting.

21.6 The larger marking is used at the start of a speed limit if approaching traffic is subject to a limit higher than 40 mph, otherwise the smaller size is used. The size of repeater markings should be appropriate to the speed indicated, with the smaller roundel being used where the limit is 40 mph or less.

MARKINGS ON ROAD HUMPS

21.7 The 2002 Regulations changed the way that road hump markings are prescribed. Diagrams 1060, 1060.1, 1061 and 1061.1 in the 1994 Regulations were replaced by the triangular marking to diagram 1062 (see figure 21-2). Other prescribed markings are used on humps as required.

21.8 Road hump profiles will generally be either round or flat-topped with ramps. Figure 21-3a shows a typical layout of markings on a round hump, and figure 21-3b on a road hump with tapered ends. Figure 21-3c indicates the markings used on flat-topped humps. Tapered ends are not used at flat-topped humps provided to help pedestrians cross the road (see para 21.17 for guidance on locating pedestrian crossings on road humps).

21.9 The triangular marking to diagram 1062 is used on the approach side of a hump. It should extend from the edge of the hump to the highest point (or for a maximum distance of 1850 mm if this is less). On flat-topped humps, the triangle marking should extend for the length of the ramp, if this is less than 1850 mm. Two triangular marks should be used in each lane; in one-way roads they should be placed only on the approach side of a road hump.

MARKINGS ON SPEED CUSHIONS

21.10 At a hump that is 5 m or more in width, unless at a Zebra or signalled crossing (see also para 21.17), the top of the hump must be marked with a line to diagram 1004 (see paras 4.12 to 4.26). This should be used on the approach to as well as over a hump, to separate the opposing flows of traffic in a two-way road. Where more than one lane is available to traffic proceeding in the same direction in either a one-way or a two-way road, the lanes should be separated by the marking to diagram 1004, and two triangular markings to diagram 1062 should be used in each lane. Care should be taken to ensure that it is evident which line marks the division between opposing streams of traffic, e.g. by widening the centre line marking to 150 mm.

21.11 Where a road hump has tapered ends which terminate within 300 mm of the kerb, edge line markings to diagram 1012.1 (see paras 4.31 to 4.38) or yellow lines to diagram 1017 or 1018.1 must be used, deflected over the hump to guide vehicles away from the taper (direction 18(1)). These should normally extend at least 6 m beyond the hump.

21.12 In some cases it might prove helpful to provide a cycle lane bypass between the kerb and the taper of a road hump. Where possible this should be in the form of a mandatory cycle lane, so that other vehicles do not enter the area. The width of the cycle lane should be between 750 mm and 1000 mm.

MARKINGS ON SPEED CUSHIONS

21.13 A speed cushion is a form of road hump occupying only part of the traffic lane in which it is installed (see figure 21-3d).

21.14 A single triangular marking to diagram 1062 should be used on the approach ramp of each cushion. Where vehicles from both directions might be driven over the same cushion, the triangular marking should be used on both approach ramps.

21.15 There is no marking prescribed for delineating the edges of a speed cushion as a warning to pedestrians. It is recommended that cushions be constructed in material which contrasts with the road surface. If a cushion is placed in the centre of a carriageway and may be approached by vehicles from either direction, hatched markings to diagram 1040 or 1040.2 may be used on both approaches.

MARKINGS ON THUMPS

21.16 A thump is a road hump which is between 900 and 1500 mm long (in the direction of travel). No markings are necessary if it is constructed from yellow reflective material. Where non-reflective material is used, it should not be coloured yellow, but should normally incorporate four (with a minimum of two) markings to diagram 1062 on each side of the thump in line with the approach lane. The markings should extend from the edge to the top of the thump and, in a one-way road, they should be applied across the full width of the carriageway. Edge of carriageway markings may be continued over the thump if desired.

HUMPED CROSSINGS

21.17 Pelican, Zebra, Puffin and Toucan crossings may be placed on flat-topped kerb-to-kerb humps (see figure 21-4). Humps may extend into the controlled areas, but the crossing must remain centred upon the hump. The detailed regulatory requirements are set out in regulation 4 of the Highways (Road Humps) Regulations 1999.

BUILD-OUTS

21.18 A build-out is a feature that extends into the carriageway on one side of the road only. It may be constructed integrally with the footway, or a gap may be left for drainage, or for cyclists where it is considered that they would be at risk of being squeezed by passing vehicles. The approach to a build-out should normally be marked using diagram 1040.4, with the taper specified in table 14-1. Where there is parking immediately preceding the taper, the markings described in para 21.20 may be used. An edge line to diagram 1012.1 may be added. Any yellow waiting restriction lines should follow the line of the kerbs around the build-out and not be stopped either side of a chicane or pinch point.

21.19 If it is intended to assign priority to traffic from one direction, Give Way and triangular markings (diagrams 1003 and 1023) may be provided, supplemented if required by signs to diagrams 615 with 615.1 and 811 with 811.1 (see also para 3.24). Note that it is not lawful to require traffic from both directions to give way. The build-out is normally used on the side of the carriageway leading into a traffic-calmed section and priority given to vehicles travelling in the opposite direction. The Railway Inspectorate should be consulted at an early stage if such an installation is planned near a level crossing.

21.20 A series of build-outs along one side of a road can be used to provide sheltered parking places. Projecting the build-out beyond parked cars also enables pedestrians waiting to cross to see and be seen. Diagram 1010 should be used to delineate the edge of the carriageway available for through traffic unless the parking is controlled by a traffic regulation order, in which case the appropriate bay marking is used (see paras 20.11 to 20.28).

21.21 If a gap is provided for cycles, it should be marked with the cycle symbol, diagram 1057, and the appropriate vertical sign. Such a gap may, however, inconvenience pedestrians using the build-out as a crossing place.

CHICANES AND PINCH POINTS

21.22 A chicane is a narrowing of the carriageway formed by locating build-outs alternately on each side of the road. Pinch points are formed by the construction of build-outs opposite one another; they may be useful at crossing places, whether controlled or not, to reduce the width of carriageway to be crossed. The approaches to chicanes and pinch points should be marked using diagram 1040.4 with the tapers specified in table 14-1.

21.23 A centre line road marking to diagram 1004 should not normally be used between the build-outs of a chicane or pinch point unless the width of each traffic lane so formed would be 3 m or more.

21.24 Any yellow waiting restriction lines should follow the line of the kerb around the build-out (see para 21.18).

21.25 Chicanes are not normally appropriate places for pedestrians to cross the road as the attention of drivers is likely to be concentrated on negotiating the features. Pedestrians should not therefore be encouraged to cross at such locations, whether by the installation of formal crossings or dropped kerbs. If, however, pedestrians are likely to cross at a chicane, the design should ensure that they can be seen clearly and that they can cross the road safely.

GATEWAYS

21.26 Gateways can be provided to indicate places where the road changes in character, e.g. where a rural road enters a town or village. They must not prevent the passage of any vehicle unless there is an appropriate traffic regulation order.

21.27 Edge lines and hatched markings can be used to make the carriageway appear narrower than it is, whilst still allowing larger vehicles to overrun these areas if necessary. The effect will be increased if a central refuge island is provided together with hatched markings, but care must be taken not to increase hazards to cyclists. In rural areas, the width of some farm vehicles needs to be considered and care should be taken not to prevent these or other wide vehicles from passing. If there is insufficient space to accommodate a physical island, a ghost island formed by markings alone can be helpful.

21.28 Edge lines and hatched markings should taper in accordance with table 14-1.

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.