Safety of Motorway Lighting

The safety aspects of motorway lighting and its capacity to prevent nighttime accidents are examined. The analysis is based on a night/day accident rate ratio method to compare the safety benefits of two alternatives to dark motorways: continuous lighting and interchange lighting alone. Various sources of data are used to calculate night/day accident rate ratios, such as traffic volume records, accident databases, and field surveys. Three categories of accidents have been used: fatal and injury accidents, property damage only, and all accidents. The results are similar to those from recent literature. Continuous lighting reduces the overall accident rate by 33 percent (p < .001) in comparison with interchange lighting alone and by 49 percent (p < .05) compared with dark motorways. Furthermore, a breakdown by categories of average daily traffic for these comparisons reveals that accident reductions are still valid regardless of traffic flow.