LARGE TRUCKS IN URBAN AREAS : A SAFETY PROBLEM?

The direct safety effects of increasing the number of large trucks in urban areas are explored. A simple theoretical model of the consequences of mixing trucks with cars is presented. The model, supported by recent detailed data from national in-depth accident investigation programs, indicates that the physical difference of mass between the two types of vehicles necessarily leads to a larger number of fatalities unless there is a concomitant reduction in the probability of such collisions. A comparison of urban and rural truck accident experience shows that the most severe urban accidents occur on urban interstate roads. Therefore, traffic engineers will be challenged by the problems associated with an increased truck population and will need to continue developing ways of reducing the chances of contact between the two types of vehicles in traffic flow.