Determination of input data for probabilistic safety assessment / Die Gewinnung von Eingabedaten für probabilistische Sicherheitsanalysen

Abstract

The application of probabilistic safety assessment in decision processes depends to a great extent on the quality of the input data. The plant specific acquisition of these data must be performed in a way which allows a reliable prediction of system failures in the future. Comfortable computer tools are available to facilitate data processing and to make use of data that are already available via the computerized plant information system. The correct classification of failure occurrences with respect to the PSA relevant failure modes requires thorough evaluation of all information available in maintenance records, test reports, and licensing event reports. The flow of information relevant to future data acquisition must be properly organized. The application of generic common cause failure data requires careful evaluation of the underlying failure causes and of the level of defence achieved in the plant under consideration to prevent too pessimistic analysis results