Abstract
ABSTRACT Probability Safety Assessment (PSA) is a holistic approach to estimate the reliability and safety of a nuclear power plant. PSA has been widely utilized by many nuclear utilities and its impact on the nuclear power plant (NPP) safety is very notable. Over the past few years, Severe Accident Management Guidance (SAMG), which delineates the mitigation actions of core meltdown accidents of NPP, is developed to support operators and staffs in the Technical Support Center (TSC) in dealing with those misfortunes. It can be expected that the implementation of SAMG will lower the risk of NPP operation. The execution of SAMG will lower the containment failure probability and will reduce the amount of radionuclides released to the environment during the accident. The mitigation actions in SAMG are not considered in the conventional Level-2 PSA analysis of PSA. In this study the mitigation actions of SAMG are incorporated into the Level-2 PSA of a Westinghouse three loops Pressurized Water Reactor (PWR). The plant analyzed is Maanshan Nuclear Power Plant of Taiwan Power Company. The purposes of the study are to assess the impact of SAMG on the risk of NPP and to identify the importance measure of these mitigation actions. This thesis summarizes the results of the study.