Page:UK Traffic Signs Manual - Chapter 3 Regulatory Signs. 2008 (Second Impression 2008).pdf/41

Rh 626.2A Maximum weight of vehicle on bridge

"78T" may be varied to "3T", "7.5T", "70T", "73T", "26T" or "33T". "BRIDGE" may be varied to "ROAD"

627.1 Exemption for unladen vehicles

May be used only in combination with diagram 626.2A

The sign to diagram 629 is used to give effect to an order prohibiting all vehicles exceeding the indicated width from being driven along a road. The order may be imposed to prevent entry to roads physically incapable of accommodating larger vehicles or to protect the environment by preventing unnecessary intrusion by large vehicles. In the latter case a physical feature might need to be installed to enforce it. Provision might be needed to permit buses to use the road and also to permit access. Where buses are excluded from an environmental width or length limit, it might sometimes be preferable to impose a lorry ban with signs to diagram 622.1A (see paras 5.15 to 5.19) unless there are other large vehicles that are to be prohibited from using the road.

The maximum width permitted, in imperial units, should be 6 inches less than the narrowest part of the road, rounded to the nearest 6 inches downwards. If this narrow part is long and not straight it might be necessary to increase the clearance to allow for long vehicle overhang at bends. If the limit is introduced for environmental reasons, a width of 6ft 6 in is frequently used, as this excludes most lorries.

The sign to diagram 629A is a combined metric and imperial version of the width limit sign. In order to maintain equivalent legibility, it is one step larger in size than diagram 629 (see Appendix A). It may be used in place of the imperial-only version, but metric units alone must not be used. It is recommended that