Hazmat transport: a comparison among routing strategies

A way to reduce the risk imposed by the transportation of hazardous materials is represented by routing, that is by the selection of alternative less risky paths in respect to those usually chosen by truck drivers. In this paper the full version of a routing model named OPTIPATH is presented. OPTIPATH solves the routing problem offering to the decision maker a wide set of different optimisation strategies, with the possibility of satisfying side constraints and optionally including the compliance with risk acceptability criteria; the model formulation is that of a multi-commodity network flow problem with global arc capacities, having the mathematical form of an integer programming problem with linear constraints. The OPTIPATH methodology has been developed in the context of Chemical-Process- and Transportation- Quantified Risk Analysis (QRA); it’s characterized by the fact that the definition of the arc attributes is heavily drawn on the risk indexes traditionally adopted in QRA. The OPTIPATH model has been integrated in a working GIS-based Decision Support System (DSS) called TRAT4-GIS, functioning on a desktop personal computer. In this paper first the theoretical fundamentals of OPTIPATH are described in detail; then a case study application to an Italian real-life routing scenario is outlined, extensively discussing results to show the main features of the model.