Identifying key performance shaping factors in digital main control rooms of nuclear power plants: A risk-based approach

Various human reliability analysis (HRA) methods use performance shaping factors (PSFs) to model operator performance. The tendency in HRA is to increase the number of PSFs. However, using many PSFs may negatively affect the quality of HRA outcomes. An elite-set PSF model with key PSFs is lacking. We therefore suggest a risk-based approach for identifying the key PSFs by ranking their risks to operator performance. In this approach, we elicit nuclear power plant (NPP) operators' perceptions of the frequency and impact of PSF indicators in main control rooms (MCRs), quantify the perceived risk scores of PSFs by multiplying their perceived frequency and impact, and classify PSF risk levels according to the suggested PSF risk matrix. Licensed operators (N = 33) from a digital NPP MCR participated in our survey. The top-ranked PSFs in terms of perceived risk score and the PSFs at the High Risk level were identified as the key PSFs from the surveyed NPP MCR. A comparison with other studies indicates that the importance of these key PSFs has been previously recognized, implying that the risk-based approach can yield meaningful results for ranking and identifying the key PSFs.