A novel methodology assessment to study the performance of the physical protection system for enhancing the security of nuclear and other radioactive materials during transport

Abstract

This paper presents a risk-informed model for securing radioactive materials during transport, integrating a real transport graph to simulate attack probabilities and response effectiveness. The model addresses the potential for adversarial attacks, including theft and sabotage, and evaluates the ability of the Physical Protection System (PPS) to detect, delay, and neutralize threats. Using a real-world transport network, we simulate the most plausible attack paths an adversary might take and assess the success probability of these attacks in relation to key system metrics: detection probability ($P_d$), communication probability ($P_c$), interruption probability ($P_i$), and neutralization probability ($P_n$). The model also considers the arrival time of the response force, as a critical factor influencing the overall security effectiveness. The transport graph represents the network of possible routes, critical locations, and access points, which are used to simulate adversary actions and response dynamics. Each edge in the graph represents a potential attack path, with associated probabilities for adversary success and system response. System effectiveness, $P_e$, is calculated by simulating realistic attack-response scenarios. Results highlight how optimized strategies reduce adversary success while enhancing response efficiency. Case studies demonstrate the model’s utility in securing radioactive materials and improving PPS designs to mitigate theft and sabotage risks.