Novices as models of expert operators: Evidence from the NRC Human Performance Test Facility

Abstract

Humans are integral to the safe operation of a nuclear power plant (NPP). Following the Three Mile Island accident in 1979, the United States Nuclear Regulatory Commission (NRC) began focusing on incorporating good human factors engineering design principles in regulation and emphasizing the importance of adequate training of plant operations staff. As part of this focus, NRC amended its regulations to require facility licensees to have simulation facilities for use in administering NRC operating tests and licensed operator requalification training (52 FR 9460). Since then, the simulator has become an important tool for operator training and license examinations. As technology develops, new designs and technology becomes available to the nuclear power community. The staff of NRC is responsible for reviewing and determining the acceptability of new designs to ensure they support safe plant operations. Since the human operator is vital to NPP safety, NRC must understand the potential impact of new designs on human performance to support sound regulatory decisions (Hughes, D’Agostino, & Reinerman-Jones, 2017). Despite the importance of human performance in plant safety, much of the basis for current NRC Human Factors Engineering guidance is from other domains (e.g., aviation, defense), qualitative data from operational experiences in NPPs, and limited empirical studies in a nuclear environment (Hughes & D’Agostino, 2016). To close this data gap, NRC launched the Human Performance Test Facility (HPFT) project to explore the impact of new designs, technologies, and concepts of operations on human performance using generic simulator platforms.One of the challenges for conducting human performance research in the nuclear domain is access to trained operators. Without sufficient sample size, it is difficult to perform analyses with adequate statistical power and draw substantial conclusions. To overcome the participant access challenge NRC partnered with the University of Central Florida (UCF) and use college students as a proxy for expert operators to study the impact of traditional and new Main Control Room (MCR) designs, technologies, and concepts of operations on performance of common NPP tasks and physiological and subjective workload. This approach follows the principle of “equal but different”. This means that students experienced simplified versions of complex tasks and the system user interface.This paper will review data collected from three experiments and summarize the evidence revealed by using novices as models of expert operators in the nuclear domain. Across the experiments novices and expert operators interact with touchscreen or desktop versions of an NPP MCR interface. Performance and workload were examined. Additionally, the studies sought to validate the methodology of the “equal but different” principle. Taken together the studies revealed that the “equal but different” method induced comparable cognitive demands in students and experts. This means that student novices can stand in for expert operators to help identify workload-related safety concerns in the nuclear domain. Future research will extend this approach to other MCR technologies, such as automation and novel control room configurations. Further, the method developed in the HPTF can be applied in other domains where access to experts is limited.