102 A Couple of Points to the Discussion about Factors Influencing Human Reliability (PSAM-0065)

Within the last decade of operation of Czech nuclear power plants, human reliability has become a point of significant interest. The Department of Risk and Reliability Analysis of Nuclear research Institute Rez (NRI) has provided various kinds of support in this area.

Somewhat abstract and theoretical approach was typical for human reliability analysis until recently, based on the conclusion that there is too little data for application of common statistical and probabilistic methods, because human behavior is both too complicated and too hard predictable to be described using a couple of statistical parameters only. This situation has partly changed last several years, as soon as it was found that relatively broad human factor related information can be found in plant operation records and mixed with additional knowledge in the mind of experienced plant specialists. Altogether, such information base makes possible to carry out various useful investigative attempts sometimes producing non-trivial results, both qualitative and quantitative, suitable for consequent applications in plant management decision-making activities.

In the paper, several pieces of effort organized within last couple of years in NRI are described with emphasis put upon detailed qualitative and quantitative analysis of factors influencing nuclear power plant staff work, based on analysis of more than one thousand event records taken from forty reactor years of NPP Dukovany operational experience.