Abstract
Many regulatory bodies worldwide have developed realistic methods for plant assessment with which to monitor the safety of nuclear power plants and to improve public awareness of plant safety. The aim of this study is to focus on risk calculation model using AIMS-PSA software to analyze Risk Achievement Worth (RAW) and Risk Reduction Worth (RRW) for APR1400 Safety Injection System and its contribution to Core Damage Frequency (CDF). This study will provide a quantitative perspective on dominant contributors to risk which will provides help to make changes in input values which is usually calculated at core damage frequency level. To apply the approach, Large LOCA initiating event is considered as it has significant impact on the operability of Safety Injection System (SIS). This study will provide a guideline to determine the appropriate inspection findings to specify any deficiency in licensee performance and identify regulatory issues or inspection findings and correlate them to the SIS basic events to verify their contribution towards CDF. For example, some components might fail due to common cause failure (CCF) or dependent failure in which two or more component faults states exist simultaneously, and have a high contribution to CDF. The result of this research is expected to assist the regulatory body in decision making, provide for more efficient use of resources and direct regulatory policy.
