The role of risk-informed approaches for advanced reactors in Korea

Abstract

Currently, various types of advanced reactors are being developed in the Republic of Korea, including (1) advanced large power reactors, (2) light water–based small and modular reactors, and (3) Generation IV reactors. While Probabilistic Safety Assessments (PSAs) have been performed for these advanced reactors in Korea, the PSAs were not conducted in detail since they were not regulatory requirements in many cases. However, the role of PSA is changing in Korea nowadays, and qualified PSA models have recently become an essential element in the licensing of operating and new reactors. In addition, PSAs for advanced reactors are essential not only to meet regulatory requirements but also to improve the safety and performance of advanced reactors. It can be said that the success of advanced reactors depends on how their safety and economics can be secured effectively and efficiently. The PSA will play an essential role in this aspect. Various risk-informed approaches (RIAs) based on PSAs are used in many countries worldwide for this purpose. A few issues remain to be resolved for the success of PSAs and RIAs for advanced reactors, such as the development of licensing frameworks for advanced reactors, the reliability assessments of passive safety systems, and so on. In this paper, we introduce the current status of PSAs and RIAs for advanced reactors, including descriptions regarding the characteristics of advanced reactors currently being developed in Korea. We also discuss some important issues to be resolved for the success of RIAs for advanced reactors. We also briefly introduce some research performed to resolve those issues.