Understanding individualistic response patterns when assessing expert operators on nuclear power plant control tasks.

Area of Science:

• Human Factors and Ergonomics
• Nuclear Engineering
• Cognitive Psychology

Background:

• Nuclear power plant (NPP) operations require highly skilled reactor operators (ROs).
• Assessing operator performance and workload in safety-critical domains is crucial.
• Existing research often seeks generalizable findings, potentially overlooking individual differences.

Purpose of the Study:

• To evaluate the performance and response strategies of highly practiced individuals in a simulated NPP control task.
• To identify diagnostic and predictive measures of operator performance capacity.
• To explore the individual-specific nature of performance-workload associations in expert operators.

Main Methods:

• Three highly practiced participants performed simulated NPP control tasks.
• Collected subjective, physiological, and objective performance measures.
• Analyzed response strategies, accuracy, and response times across sub-tasks.

Main Results:

• Observed ceiling effects in performance accuracy, indicating experts reached maximum capability.
• Each participant employed unique response strategies for different sub-tasks.
• Maximized accuracy was associated with increased response times, suggesting a speed-accuracy trade-off.
• Performance-workload associations were found to be operator- and task-specific.

Conclusions:

• Expert operator performance in NPP control is characterized by individual strategies and trade-offs.
• Standardized assessments may be insufficient; an idiographic approach focusing on individual operators is necessary.
• Findings have implications for training, assessment, and safety in safety-critical operational domains.