MODELING OF SAFETY MEASURE EFFECTS AND RISK COMPENSATION

A model is proposed for the description of effects of safety measures introduced into a road transport system. The model explains the motive s of road users' risk compensation towards the measures, and indicates when behavioural adaptation is likely to take place and its effects o n road safety programmes. At its core the model has the notion that wh en a transport system is changed by engineering safety measures, road users do not respond only in the direction towards safety improvement but respond, in general, with three possible ways of behavioural adapt ations, one of them towards more risk taking. Supported by illustrativ e examples, it also suggests that due to risk compensation, engineerin g safety measures alone are usually not sufficient, and, hopefully, ca refully designed motivational safety measures can give us chances to m odify road users' behaviour to make traffic safer.