A security vulnerability analysis model for dangerous goods transportation by rail – Case study: Chlorine transportation in Texas-Illinois

Abstract Transportation of dangerous goods has always been in the spotlight of terrorist groups with the aim of inflicting severe harm to humans and the environment. The purpose of this paper is to present a security vulnerability analysis approach to find critical areas along railway transportation routes specifically with regard to trains carrying dangerous goods. In this study, ALOHA and ArcGIS software are used for checking the security vulnerabilities and to estimate the population and affected infrastructure due to a malicious attack. Chlorine transportation on the Texas-Illinois rail corridor (in the US) is studied by developing a routing model. The priorities of the infrastructure for the terrorist’s attack are a variety of land use types as sports, educational, commercial, and health centers; religious places; government buildings; airports; parks; and museums. In addition to the infrastructure, the size and the density of the population within the threat zone are main items for the terrorist to plan the attack. With demographic layers in the GIS software, the number of people residing in the study area that are exposed to the attack is identified. A zero-sum game theoretic approach is employed to model the interactions of terrorist and operator's strategies. After running the model, (i) the operator’s route selection probabilities are calculated, and (ii) the terrorist’s target link selection probabilities are also determined. This paper shows that how critical links can be identified for different terrorist purposes, which could be the subject of further security measures.