Hazard assessment of major accidents triggered by intentional acts of interference

A growing attention was devoted in the last years to the analysis of the risk deriving from external hazard factors, as natural events and intentional acts of interference (as terrorist attacks), in industrial sites where relevant quantities of dangerous substances are stored or handled. In the case of intentional acts of interference, the methods used to assess the related hazard have focused mostly on “security” rather than on “safety”. In this paper, a new procedure for the assessment of the hazard posed by malicious acts of interference is presented. The procedure aims to the evaluation of the expected consequences of malicious acts of interference, in terms of release rates and damage distances, with an approach based on the further development of conventional techniques used in quantitative risk assessment. The method developed was applied to a case study in order to understand its potentialities and the results that may be obtained.