RSAS

This paper reports on the Reactor Safety assessment System (RSAS) which is an expert system being developed by the Idaho National Engineering Laboratory (INEL) and the United States Nuclear Regulatory Commission (NRC) for the NRC Operations Center. RSAS is intended to aid the Reactor Safety Team at the Operations Center to monitor and project core status during an emergency at a licensed nuclear power plant. The foundation of the RSAS knowledge base is a Goal Tree-Success Tree (GTST) model. Critical safety functions appear as upper level goals in the GTST model. Success trees represent the functionality of systems and equipment required to achieve the desired goals. A dependency matrix is utilized to account for functional dependencies among various systems and equipment. RSAS objectives are obtained by the monitoring of the critical safety functions, identification of success path status, and timely provision of vital information