Research on the interrelation between Illuminance at intersections and the reduction in traffic accidents

摘要

One recent apparent trend in increasing traffic accidents in Japan is the increase in night-time accidents. To address this problem, various traffic safety measures have been introduced aimed at safer road traffic environments. Among these measures, road lighting, in particular 'local lighting', has been introduced in increasing numbers as a counter-measure against night-time accidents. However, in terms of the number of fatal accidents by road profile, the 'at intersection' accounts for the largest portion of the fatalities. Therefore, more effective intersection lighting measures must be studied. This paper discusses the illuminance levels expected for intersection lighting from the viewpoint of traffic accident reduction and reports the results. The means used were a review of accident data and statistical analysis before and after the introduction of accident counter-measures. It was learned that an average road surface illuminance at intersections maintained at 20 lux or higher, can provide an effective accident countermeasure, and that an average road surface illuminance of 30 lux can further develop a statistically significant reduction in traffic accidents.