PSA-LOPA. A novel method for physical security risk analysis based on layers of protection analysis

Physical security risk analysis represents a fundamental tool to evaluate the threats regarding an organization and it can be divided into distinct groups, represented by: qualitative, semi-quantitative, quantitative, and mixed. The method of analysis is very important because it also allows to measure the increase in the level of security following the improvements of planned activities to step-up the levels of protection of a given site. In our case, the Layers of Protection Analysis (LOPA) method, initially structured and developed for industrial plants safety (such as chemical industry), has been revised and adapted to the physical security risk, providing interesting and useful results. The purpose of this paper is to illustrate a novel method for physical security risk analysis based on LOPA that represents a general tool for any kind of organization.