Traffic calming can help drivers to make their speeds appropriate to local conditions, through measures which are self-enforcing. This leaflet provides an explanation of the Highways (Traffic Calming) Regulations 1993, and offers guidance on the use of measures prescribed in the regulations. More comprehensive guidance on traffic calming devices will be the subject of further leaflets.
Road humps, including speeds cushions etc., have their own specific legislation. Therefore only brief reference is made to these features. The references at the end of this leaflet provide information on where current guidance on road humps can be found.
Traffic calming schemes may have both environmental and safety objectives. These are best achieved by a multi-disciplinary approach. This ensures that the expertise of road safety officers, landscape architects, planners, conservation officers, and other professionals can be brought into play at an early stage in scheme design. Public utilities should also be involved, as the location of their apparatus can influence the design and cost of a scheme.
A jigsaw image
The Traffic Calming Act 1992 amended the Highways Act 1980 by the addition of Sections 90G, 90H and 90I which allow works to be carried out "for the purposes and promoting safety of preserving or improving the environment....." The Act made the first specific references in legislation to traffic calming. However, it does not preclude the use of other powers in the Highways Act 1980 and elsewhere under which traffic calming features can be provided. The relevant powers in the Highways Act 1980 include:-
|
Section 64 |
roundabouts; |
|
Section 68 |
pedestrian refuges; |
|
Section 75 |
variations in the relative width of carriageways and footways; |
|
Section 77 |
alterations in the level of a highway; |
|
Sections 90 A-F |
road humps |
In addition the 1992 Act does not prevent traffic signs prescribed under the Traffic Signs Regulations and General Directions being used for traffic calming.
These regulations came into effect in August 1993. They have been made to provide local highway authorities with the necessary powers to construct particular measures for traffic calming purposes which are not otherwise clearly authorised.
The regulations prescribe features which can be used alone or in combination with others, either prescribed by these same regulations or which can be constructed under powers provided under other legislation, or which have been specially authorised.
Gateways
Islands
This includes such features as rumble strips, rumble areas, jiggle bars etc. For general use on public roads, devices must not exceed 15mm in height and no vertical face must be greater than 6mm. In the case that authorities wish to use devices which exceed these dimensions they must seek special authorisation. However the reason for stipulating these dimensions in the regulations is the concern that rumble devices should not be dangerous to vulnerable road users. For the safety of cyclists a gap of not less than 750mm should be left between the rumble device and the adjacent kerb or verge to allow them free passage. Some schemes only extend rumble devices over one half of the carriageway. It has been known for drivers to avoid these rumble devices by driving over the half of the carriageway provided for opposing traffic. For this reason it is generally recommended that rumble devices are placed across the full width of a two way road. The speed control qualities of rumble devices over a long period are not entirely proven. Further information is being collected on this aspect as well as various design features. It appears that they can be used as an effective alerting device, and there are claims of accident reductions occurring at some locations. A major drawback of rumble devices is the noise they can generate, and for this reason they are not recommended for use in urban areas. Some authorities will not permit their use within 200m of any residential property, but anecdotal evidence suggests that the noise generated can travel much further, depending on local circumstances. It is recommended that rumble devices are constructed in a contrasting colour from the road surface, though not white in order to avoid any confusion with road markings.
These are areas which are usually constructed to form a raised surface but may also be areas in a contrasting colour. They may be sited adjacent to the kerb, either at the near side of the road or at an island. The purpose is to create an appearance of a narrower carriageway in order to inhibit speeds of vehicles, but at the same time allow drivers of larger vehicles to negotiate the feature. As cyclists and motorcyclists may at times be forced to ride across these areas, the regulations stipulate that no vertical face should exceed 6mm. Higher vertical faces could cause them to lose their balance. Materials which incorporate radius or irregular upstands will generally not be affected by this requirement. However, the slope angle of 15( should not be exceeded as this again could cause danger to certain road users. Overrun areas should not be positioned where pedestrians are likely to cross the road. They may be tempted to stand on the overrun area, where they could be at risk from large vehicles negotiating the device. Alternatively, if an irregular surface is used, pedestrians may be influenced to cross at a more dangerous location. In siting overrun areas consideration therefore needs to be given to their relationship to the places where people are likely to cross.
Build out
Seeking the views of those affected by traffic calming schemes is vital in determining the success or failure of any scheme. The regulations require that the police be informed of traffic calming proposals; they have day to day responsibilities for traffic control, and it is essential that they have the opportunity to comment on matters which might affect this. The regulations make it clear that consultation with other organisations is a matter for highway authorities to determine. Some minor work, for example, may require little or no consultation. However, where any traffic calming works will materially affect the movement of traffic, be it pedestrian or vehicular, it is strongly recommended that consultation with road users is carried out.
Works constructed in accordance with the regulations may be paved, lit and landscaped. Not all schemes will necessarily lend themselves to planting. Where appropriate the provision of trees and shrubs can add enormously to the aesthetic value and acceptability of a scheme to the public. Planting must not obscure pedestrians, particularly children, when crossing or playing in the road. Whether or not a particular feature will require additional lighting is a matter for the local highway authority to determine, bearing in mind the conspicuity requirements of these and other regulations.
Many traffic calming schemes are designed to inhibit vehicular access to a road or area. The intention is usually to discourage through vehicles. Entry treatments are often used to create this effect. However, the regulations make it clear that traffic calming measures cannot be used by themselves as a means of prohibiting access to certain vehicle types. Traffic Regulation Orders are required if the intention is to prohibit vehicular access; these can then be complemented on the street by the use of calming.
Within a 20mph Zone the regulations allow roads highway authorities the option of not signing the various prescribed measures. This is similar to the relaxation in the Road Humps (Highways) Regulations 1990. Signing should be provided where a local highway authority considers it appropriate to ensure that the measure operates safely. For areas when are not in 20mph zones, highway authorities should consider whether road users have a clear indication of the correct paths to follow, and if not, to provide suitable signing. If authorities wish to use signs which are not prescribed in the Traffic Signs Regulations and General Directions, they should seek authorisation from the appropriate Department. Authorities may consider signing to be unnecessary where the measure will be conspicuous.
The regulations do not require monitoring to be carried out. However, local authorities will often wish to know how a particular scheme has performed, for example to ascertain whether the objectives of the scheme have been achieved. Such objectives may include accident reduction, lower vehicle speeds, and vehicle diversion. Local highway authorities are therefore advised to consider the need for before and after studies at an early stage to ensure that relevant data can be obtained.
The regulations will assist local authorities to achieve a wider range of objectives in a number of their policies. For example, objectives relating to conservation in historic town centres, improvement of safety and environmental conditions in residential areas, and the improvement of distributor roads which are also shopping centres. In meeting these objectives authorities will need to consider carefully the range of measures to be used in order to match them to the activities in different streets. Schemes which encourage the smooth flow of traffic, at speeds in keeping with the character of the area, and with adequate provision for vulnerable road users, are most likely to achieve these objectives.
The traffic calming regulations are intended to provide for most features not covered by other legislation. Knowledge of traffic calming features is still being gained. The Department does not wish to inhibit the use of innovative designs. All highway authorities have a duty of care to ensure as far as reasonably possible that the designs are safe. Procedures exist which enable the Department to be able to specially authorise features which do not conform to measures prescribed by existing regulations, both for vertical and horizontal deflections. The Department encourages local highway authorities to seek special authorisation of innovative measures where appropriate. Traffic Advisory Leaflet 3/93 provides further information on this.
A - Technical:
Traffic Policy Division
Room C10/13A
2 Marsham Street
London SW1P 3B
Tel: 0171-276 6299
B - Administrative:
Traffic Policy Division
Room C10/12
Marsham Street
London SW1P 3EB
Tel: 0171-276 6287
Traffic Calming Act 1992. HMSO, ISBN 0-10-543092-7
£1.45
Highways (Traffic Calming) Regulations 1993 (SI 1993 1849)
HMSO. £1.10
Highways Act 1980. HMSO, ISBN 0 10 546680 8 £16.30
Traffic Signs Regulations and General Directions 1981 as
amended, HMSO
Highways (Road Humps) Regulations 1990 (SI 1990 No 703, and
SI 1990 No 1500) HMSO £1.70 and £0.55
Traffic Advisory Leaflet 1/87 - Measures to Control Traffic
for the Benefit of Residents, Pedestrians and Cyclists -
Available free from contact B above
Traffic Advisory Leaflet 2/90 - Speed Control Humps -
Available free from contact B above
Traffic Advisory Leaflet 3/93 - Traffic Calming Special
Authorisations - Available free from contact B above
DOT Circular Roads 2/93, The Highways (Traffic Calming)
Regulations 1993
The Traffic Advisory Unit (TAU) is a multi-disciplinary group working within the Traffic Policy Division in the Department of Transport. TAU seeks to promote the most effective traffic management and parking techniques for the benefit, safety and convenience of all road users.
TAU sponsors a wide range of research into traffic management issues, much of it undertaken by the Transport Research Laboratory.
Enquiries, and requests for unpriced TAU publications
to:
Traffic Policy Division, Great Minster House, 76 Marsham
Street, London, SW1P 4DR.