M. Bell et al. (eds.), Security and Environmental Sustainability of Multimodal Transport, 23 Risk Averse Routing of Hazardous Materials with Scheduled Delays Chiara BERSANI 1* , Riccardo MINCIARDI 1 , Angela Maria TOMASONI 1,2 , Roberto SACILE 1 1 DIST, Department of Communication, Computer and System Sciences, University of Genova, Italy 2 MINES Paris Tech – ARMINES, Ecole des Mines de Paris, CRC, Centre for Research on Risk and Crises, Sophia Antipolis, France Abstract The term “risk-averse” in the routing of hazardous material is used for problems whose objective is to find the best and safest routes to connect various origin-destination (OD) pairs, taking into account the objective of minimizing either the maximum risk or the maximum exposure. In recent works, it has been demonstrated that for repeated shipments, where the accident probabilities over the various links in the network are unknown, the safest strategy is generally based on the use of a multiple routes for each OD pair. In this work, it is shown that further improvements can be made through scheduling the deliveries, that is, spreading the risk both in space and in time. The scheduling is particularly relevant when the vulnerability of the network is time-dependent. Keywords: Hazardous material transport, risk averse routing, link exposure, game theory, decision support system Introduction The increasing need for sustainable freight transportation taking into account economic, environmental, and risk aspects, requires models which enhance the overall transport planning process. As far as hazardous material (hazmat) transport is concerned, current decision making tools do not significantly differ from traditional planning tools for general freight, in that they compute and recommend the routes based mainly on the economical factors (distances covered and transport costs). However, from a sustainable transport viewpoint, the best route choice may also depend on risk and safety aspects which are often in conflict with economic efficiency. In addition, hazmat transport risk lacks a worldwide accepted definition. Even though several recent scientific papers discuss this issue [1–5], further work is required to agree a standard definition. It must be also noted that events with __________ * Corresponding Author: Chiara Bersani, DIST, Department of Communication Computer and System Sciences, University of Genova, Italy, University of Genova, via Opera Pia 13, 16145 Genova, Italy; E-mail: chiara.bersani@unige.it DOI 10.1007/978-90-481-8563-4_2, © Springer Science + Business Media B.V. 2010