Requirements on Human Factors Methods for Evaluating Safety in Future Nuclear Power Plant Control Rooms

There is an on-going process of modernisation of Swedish nuclear power plants, and also new plants are being built around the world. When control rooms are modified it is highly significant to maintain safe operation of the plant. Therefore it is important to evaluate the control room from a human factors perspective.The purpose of this study was to provide input to assess the suitability of present human factors methods to evaluate if future Swedish nuclear control rooms support safe operation. The aim was to suggest requirements that human factors evaluation methods must fulfill to be useful in this matter. The requirements were based on presumptive usability problems important to attend to, which were found from an interview study regarding future control room changes with seven professionals from the Swedish nuclear business.The resulting requirements on human factors evaluation methods found were: an ability to evaluate cooperation within the shift team, operator workload and the design and use of digital operating procedures; an ability to identify usability problems that may lower operator situation awareness, inconsistencies between operator interfaces, work tasks that create extreme levels in mental workload, inefficient and/or conflicting work tasks, information and control devices necessary for various work tasks and users, usability problems connected automation, and inconsistencies between the operators’ mental model of the system and the system itself.To conclude, the requirements set on human factors methods for evaluation of safety in control rooms can be used to assess if existing human factors evaluation methods are appropriate. This in turn will give input to study if and how the existing methods can be improved