System reliability: an example of nuclear reactor system analysis

This paper presents an overview of the three reliability investigations of a 900 MWe reactor residual heat removal system. Following a description of the system and its functions, the main procedures used in operational reliability analysis, based on the analysis of occurrence records, are covered. The second part of the investigations covers predicted reliability, involving the use of the Markov method. It will be noted that the two types of analysis are in good agreement, the probability of system loss after two months' operation being of the order of 10-1. Additional investigation data are also given. (author)