Samenvatting
In Switzerland the proportion of night accidents is on average 30%. Regarding the traffic concentration during the night the risk for an accident in particular in rural areas is very high. For decreasing this risk street lighting is one of the best solutions. The level of average luminance is an important factor. In the night the traffic safety increase when the street lighting increases. The luminance seems to be the best at 5 to 6 cd/m2.