Crew Situation Awareness, Diagnoses, and Performance in Simulated Nuclear Power Plant Process Disturbances

Research was conducted at the OECD Halden Reactor Project to identify issues in crew performance in complex simulated nuclear power plant scenarios. Eight crews of operators participated in five scenarios, administered over a two or three-day period. Scenarios required either rule-based or knowledge-based problem solving. Several performance parameters were collected, including Situation Awareness (SA), objective performance, rated crew performance, and crew diagnoses. The purpose of this study was to investigate differences in performance measures in knowledge-based and rule-based scenarios. Preliminary data analysis revealed a significant difference in crew SA between the two scenario types: crews in the rule-based scenarios had significantly higher SA then crews in the knowledge-based scenarios. Further investigations were initiated to determine if crews performed differently, in terms of objective performance, rated crew performance, and diagnoses, between the scenario types. Correlations between the various crew performance measurements were calculated to reveal insights into the nature of SA, performance, and diagnoses. The insights into crew performance can be used to design more effective interfaces and operator performance aids, thus contributing to enhanced crew performance and improved plant safety. (authors)