IMPROVED DIRECTION SIGNS AND THE BENEFITS FOR ROAD USERS

The work reported in this paper tries to quantify the effect that direction signs have on driver's route choice. Data from the Gloucestershire and Avon study are used together with information from the existing directional signs and analysed in a special suite of computer programs - signpost'. The programs were developed to select place-names that should appear on direction and confirmatory signs conforming to a minimum cost route. Signs developed by the use of signpost' are compared with existing signs and methods of identifying inconsistencies are discussed. It was found that in the Gloucestershire and Avon area, an average of 7 place names per intersection, and 1 directional change every 20 intersections needed changing. Although over 75 per cent of the drivers interviewed claimed that they took the quickest or shortest route, analysis showed that about 50 per cent achieved their stated objective, while 86 per cent followed the logically signposted route. Cost benefits of changing signs could be high in terms of time and fuel savings. There is a 40 per cent chance that the annual rate of return on a single investment of found22 M could be returned in 2 days saving. Results suggest that there are substantial savings to be made by improving the accuracy and consistency of signing. (TRRL)