The current speed limit for trucks on dutch motorways is violated on a large scale. In order to formulate recommendations for policy measures it is necessary to have insight into the determinants of speed choice of truck drivers. The aim of the present study is to gain insight into the main determinants of habitual speed choice and into the motives that determine the differences in speed choice. Fishbein and ajzen's model of reasoned action has been applied in the present study. The data were collected by means of a mailed questionnaire among a sample of truck drivers and transport companies. The response percentages were respectively 63% and 56%. It appears from the results that most truck drivers drive between 80 and 90 kmh and that only a small group drives over 95 kmh. The intention of driving fast is strongly related to the actual driving speed, with the attitude to speeding and with the subjective norm with respect to speeding. To determine the actual driven speed, the attitude is more important than the subjective norm. The most important consequences that determine the attitude are: driving economically, driving comfortably, driving safely, being fined and keeping the truck in a good condition. The most important reference groups that determine the subjective norm are the police and the employer. The study has provided a good basis for modifying speed behaviour by means of publicity campaigns.
Samenvatting