Development of cyber risk analysis framework for core computational system of TRIGA reactor using graded approach

Among digital transformation, the TRIGA reactors highlighted the necessity to evaluate vulnerabilities and countermeasures of its I&C system against cyber threats because of its linkage to the reactor core. The objective of this study was to develop the cyber risk analysis framework for the TRIGA reactor using the graded approach based on the IAEA Technical Guidance. The series of TRIGA reactor cyber assessment framework were suggested with the methodologies from nuclear power plants and related industries that used the core computational system. The framework practice was implemented in the actual TRIGA reactor in Thailand. The equipment of the reactor protection system and reactor regulating system in the I&C system was considered as assets weakness to quantify cyber risk. Countermeasures were suggested to secure the system and realize the vulnerabilities due to insider threats, inactive network monitoring, and no strong physical protection levels for decreasing the cyber risk in the country.