Modeling of transport risk for hazardous materials

The transport of hazardous materials is an important strategic and tactical decision problem. Risks associated with this activity make transport planning difficult. Although most existing analytical approaches for hazardous materials transport account for risk, there is no agreement among researchers on how to model the associated risks. This paper provides an overview of the prevailing models, and addresses the question ‘Does it matter how we quantify transport risk?’ Our empirical analysis on the US road network suggests that different risk models usually select different ‘optimal’ paths for a hazmat shipment between a given origin–destination pair. Furthermore, the optimal path for one model could perform very poorly under another model. This suggests that researchers and practitioners must pay considerable attention to the modeling of risks in hazardous materials transport.