Abstract
The author refers to Americe.n research on the relation between street 1 ghting and traffic accidents. A high percentage of accidents are due to failure to see, for one reareason or another. The street lighting must be regarded as a tool, made use of by the driver- to enable him to detect objects. Reaction time and "shock period" differ from one individual to another and depend on circumstances, but their importance is much reduced where everything is clearly visible. The nervous strain of driving is reduced by good street lighting and the glare from approaching vehicles in diminished.