On the Inclusion of Organizational and Managerial Influences in Probabilistic Safety Assessments of Nuclear Power Plants

This work identifies several characteristics of management quality and investigates possible ways of including organizational and managerial influences into Probabilistic Safety Assessment (PSA). It is concluded that the current PSA methodology can be improved in at least three ways: by reevaluating the frequency of the “other” category of failure scenarios, which is currently assumed negligible; by reassessing probability distributions of the parameters (failure rates, human error rates, and so forth) to include organizational and managerial factors; and by assessing correlations among these parameters. We also point out that the “safety culture” of the nuclear power industry is closely tied to its specific technology. Only through a thorough understanding of the licensee’s knowledge of the response of plant systems and the potential consequences of accident sequences can one assign a proper measure to the importance of organization and management to plant safety.