Developing a speed management assessment framework for rural single carriageway roads

The last national advice to local authorities on setting local speed limits was provided in DETR Circular 1/93. This report proposes the revision of this Circular should include a more consistent approach to defining a national speed limit regime, linked to road function and road quality. The approach is based on identifying the speeds at which safety and mobility costs, taken together, are minimised. This is done separately for major and minor rural roads. For each group, the final choice of limit is dependent on accident rate, and on ensuring that environmental and social objectives are considered and that acceptable speeds can be achieved. Setting speed limits should be seen as an integral part of rural safety management, and the procedures proposed encourage engineers to consider improvements to reduce accident rates, and thus allow a higher speed limit to be sustained, as an alternative to reducing speed limits.