1995

Lehtinen, Esko

The fundamental principle in the safety technology of nuclear power is embodied in the strategy of defence in depth. The defence lines of the strategy, completed with a PSA logic model and structure, are considered to provide an appropriate framework for identification and structuring of the operational safety performance areas for nuclear power plants. Once these areas are identified the safety indicators can be defined. Based on this approach a concept of safety indicator system was outlined. About one hundred indicator specifications have been collected, refined and related to the performance areas. The specifications enable the utilities and authorities to check the coverage of their indicators set from the operational safety point of view and select or refine indicators for testing and routine use. Finally various statistical approaches and methods for using indicators in performance evaluation are presented.