Examination of security risk analysis for hypothetical small modular reactor by using a fuzzy bayesian network

Abstract

Small and modular reactor (SMR) has several features that are designed to improve the safety and security of the plant. However, the decrease in size and smaller facilities may cause undesirable consequences once a security incident happen. Therefore, the SMR security system should satisfy both the need of security integrity and cost-effectiveness. This paper suggests a new approach in designing and evaluating the hypothetical SMR facility physical protection design. A fuzzy-bayesian network has been developed to model the SMR characteristics and cost-effective allocation of security measures. This method is selected to overcome the uncertainty due to the lack of information on conceptual SMR facility design. Case study then developed to evaluate the plant’s reliability against security threats and compare security cost of different scenario. The result shows that SMR physical protection system gave better security risk value compared to the large nuclear power plant under the assumed conditions. The proposed methodology has shown to be able to identify the most effective physical protection system to be established in a SMR facility. Based on the results, recommendations regarding the optimal physical protection system design to strengthen SMR security were proposed. These methods and case study have implications in suggesting new security protection measures, improved SMR physical protection system evaluation model, and a cost evaluation tool to evaluate the SMR security implementation strategy.