Coordination breakdowns in nuclear power plant control rooms: cause identification and behaviour-sequence analysis

Abstract

This study aims to identify the causes of coordination breakdowns among control crews and to understand their coordination-behaviour patterns during emergencies in nuclear power plants (NPPs). On the basis of in-depth interviews with 18 control-crew operators, we identified 25 causes of coordination breakdown related to work processes, personnel, and situation and organisation. In addition, we observed 12 control-crew training sessions that dealt with emergencies and conducted lag-sequential analysis. The levels of coordination effectiveness were evaluated using the proportion of coordination breakdowns and the anticipation ratio. We found that higher-performing teams exhibited more non-random coordination behavioural patterns than did lower-performing teams. Coordination-behaviour patterns specific to the higher-performing teams included adaptive workload management (from senior operators) and proactive seeking performance monitoring (from junior operators). The findings of the study enrich our understanding of the critical factors and processes that influence coordination effectiveness of NPP control crews. Practitioner summary: Causes of coordination breakdowns among control crews of NPPs were identified based on in-depth interviews with control-crew operators, and behavioural-pattern analysis of control crews in 12 training sessions were analysed to reveal the patterns that differentiate higher- and lower-performing teams. The findings of the study enrich our understanding of the critical factors and processes that influence the coordination effectiveness of NPP control crews. Abbreviations: NPP: nuclear power plant; RO: reactor operator; TO: turbine operator; CO: coordinator; SRO: senior reactor operator