Human performance contribution to risk in nuclear power operating events

This paper presents results of a study of the contributions of human performance to risk in operating events at commercial nuclear power plants. The Nuclear Regulatory Commission (NRC) sponsored the study, which was performed by the Idaho National Engineering and Environmental Laboratory (INEEL). The NRC Accident Sequence Precursor (ASP) Program and the Human Performance Events Database (HPED) were used to identify safety significant events in which human performance was a major contributor to risk. Conditional core damage probabilities (CCDPs) were calculated for these events using Systems Analysis Programs for Hands-on Integrated Reliability Evaluation (SAPHIRE) software and Standardized Plant Analysis Risk (SPAR) models. The results showed that human performance contributed significantly to the analyzed events.