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Control room operating crews are a crucial component in maintaining the safety of nuclear power plants. The primary support to operators during disturbances or emergencies are numerous emergency operating procedures. Further support is provided by reoccurring crew training in which the crews practice on handling anticipated disturbances in full-scale simulators. Due to the complexity of nuclear power plants and the small number of previous accidents to learn from, every possible accident scenario cannot be covered by the procedures and hence not trained on in the simulator. This raises the question of how operators can be prepared and able to cope with unexpected events by other means. This thesis investigates the possibilities of operating crews to act flexibly in situations where stable responses in the form of prescribed actions sequences from procedures cannot be applied. The study is based on the safety research paradigm of resilience engineering and the four cornerstones of resilience; learning, monitoring, anticipating, and responding (Hollnagel, 2011). The meaning and applicability of the resilience cornerstones were examined by interviewing a domain expert at the time employed by the OECD Halden Reactor Project. Subsequently, eight semi-structured interviews with operator training personnel at a Swedish nuclear power plant provided the main data of this study. This study shows that the resilience cornerstones were applicable to the work of nuclear power plant crews during emergency operations. In addition, the study provides findings regarding which artefacts (e.g. procedures) or crew characteristics (e.g. ways of communicating) support the cornerstone functions. The base thesis is that procedures always shall be used, but in situations where an operator perceives that no procedure is applicable, the crew have an opportunity to discuss the problem to come up with some other solution, i.e. act flexibly. Some trainers argued that the room for flexibility is there when needed, but it is not as certain how much flexibility and what kind of flexibility the operators are given. However, it does not seem like the flexibility, or lack of flexibility, given to operators is in itself the most problematic issue in the preparation of crews for unexpected events. Instead, this study identified several other problems of training and everyday work that could negatively affect crews’ capability to handle unexpected events. On the other hand, the trainers highlighted communication and teamwork to be important when the unexpected strikes and that much focus have been shifted towards such issues in training. Hence this can be claimed to be an important contribution given by the training today in successfully handling unforeseen events. |
