On comparing PRA results with operating experience

Abstract A procedure is presented for quantifying the consistency between probabilistic risk assessment (PRA) results and corresponding plant-specific operating data not considered in the PRA. The method, which is easily implemented in practice, is based on the use of Bayes p -values for the predictive probability that the observed data would have been produced from the PRA results in conjunction with an assumed binomial or Poisson sampling distribution. Uncertainties in both the PRA results and the operating data are considered. The method is used to quantify the consistency between PRA results and operating data for high-pressure coolant injection system unreliabilities at 11 US commercial boiling water reactors.