An example of quantification of the increase of risk level due to attacks terroristic in the transportation of dangerous goods

In this work, in order to evaluate the risk associated with the transport of dangerous goods including scenarios caused by terrorist attacks, attention has been focused on an urban area. The study has been applied to the downtown of Messina, located in Sicily. The territory of Sicily is characterised by a high concentration of chemical plants, mainly petrochemical and refineries, and thus is an area with a great risk of industrial accidents; in addition to this there are several natural risk sources. Petrochemical and refinery plants process about 50·106 t/yr of oil. This causes an over-production compared to the regional needs, and therefore a large part of these substances is exported; thus the region is characterised by an inflow of raw materials and an outflow of final products. As a consequence there are urban areas subject to an intense traffic of hazardous materials and safety cannot be ensured. The paper focuses attention on the application of the quantitative risk analysis to the case study, in order to evaluate the risk associated with the transport of dangerous goods including scenarios caused by terrorist attacks in an urban area. A complete inventory of dangerous substances was the basis of a complete risk analysis. The study has been applied to the case study focusing attention on two types of incidental events, explosions and toxic dispersions. The work has permitted the quantification of the increase of the risk level associated with terrorist attacks in the transportation of dangerous goods using an appropriate approach and then the damage areas have identified. The proposed approach will allow the definition of appropriate emergency procedure for this kind of event and protection measures for potential targets.