Development of a quantitative evaluation method for non-technical skills preparedness of operation teams in nuclear power plants to deal with emergency conditions

Many statistical results from safety reports tell that human related errors are the dominant influencing factor on the safe operation of power plants. Fortunately, training operators for the technical and non-technical skills can prevent many types of human errors. In this study, four important non-technical skills in safety critical industries – medical, aviation, and nuclear – were selected to describe behaviors of operation teams in emergency conditions of nuclear power plants (NPPs): communication, leadership, situation awareness, and decision-making skills. Also, preparedness of the non-technical skills was defined, and a quantification method of those skills called NoT-SkiP (Non-Technical Skills Preparedness) was developed to represent ‘how well operation teams are prepared to deal with emergency conditions’ in the non-technical skills aspect by analyzing monitoring-control patterns and a verbal protocol. Two case studies were conducted to validate the method. The first case was applied to Loss of Coolant Accident (LOCA) and Steam Generator Tube Rupture (SGTR) training. Independent variables were scenario, training repetition, and members. Relative values of the NoT-SkiP showed a consistent trend with changing scenarios. However, when training was repeated with the same scenario, NoT-SkiP values of some team were changed. It was supposed that leaders of some teams exerted their knowledge acquired from the previous training and gave up thoroughness of using procedures. When members especially who play a dominant role in teams were changed, values of the NoT-SkiP were significantly changed. Nine teams participated in Interfacing System LOCA (ISLOCA) training; six teams failed to complete the given task, and three teams succeeded. The comparison of NoT-SkiP values of ISLOCA case with Operator Performance Assessment System (OPAS), which mainly check operators’ knowledge and the technical skills, developed by OECD Halden Reactor Project (HRP) gave a plausible reason why teams failed as well as intuitive results on ‘what to be considered in the non-technical skills aspects of teams’ for the next training. The proposed method requires more experiments in order for it to be established on a firm foundation; however, it certainly gives one possible way to supplement existing training strategy in the nuclear industry.

► We selected important non-technical skills for emergency conditions in NPPs.
► We proposed an evaluation method for the selected non-technical skills.
► We conducted two sets of training, 9 experiments each, with real plant operators.
► Teams showed consistent non-technical skills preparedness with changing scenarios.
► Non-technical skills preparedness gives plausible explanations why teams fail tasks.