The impact of street lighting on night-time road casualties

An investigation into the impact of street lighting on night-time road casualties was carried out in order to provide highway authorities with a robust methodology for preparing cost benefit analyses of new, and refurbishment or replacement of old road lighting schemes, in relation to safety benefits. Significant changes in the efficiency of modern lighting, developments in vehicle design and increases in traffic levels mean that current UK guidance may require updating. Information from local authorities in Great Britain and the national road accident database was used in the study. Night time accident data were studied and correlated with the lighting system in use, in order to determine the relationships among the presence of lighting and the frequency or severity of accidents on different classes of road. The findings of the study to date show that there are many interacting variables affecting accident rates, making the separation of the effect of street lighting difficult. The analysis carried out shows an apparent benefit in accident savings due to lighting, but confidence in the size of the benefit is low and should be improved when the study is completed.