Multi-objective programming approach for routing hazardous materials

This paper examines the systemwide routing of hazardous materials as a means of reducing the threat to the population residing along the links of an entire transportation network. A multi-objective decision-making model is used for the mathematical formulation of the routing problem. The proposed model includes the following objectives: (1) Minimization of risk; (2) minimization of risk of special population categories; (3) minimization of travel time; and (4) minimization of property damages. A capacitated and a noncapacitated version of the multi-objective routing problem are presented. A hypothetical network is used to display the applicability of the proposed model. For the example under consideration it is shown that the imposition of capacity constraints on the links of the network tends to distribute the risk in an equitable manner while it increases the total risk by 35%.