Activities on component reliability under the OECD Nuclear Energy Agency

The Organisation for Economic Co-operation and Development (OECD) Nuclear Energy Agency has 27 Member countries. Under the auspices of the Nuclear Safety Division are two senior committees dealing with regulatory aspects (CNRA) and technological aspects (CSNI). Under these two committees activities relevant to component reliability are carried out under the three Principal Working Groups (PWGs): PWG-I on operating experience, PWG-3 on integrity of components and structures, and PWG-5 on risk assessment. Although the principal interest of these committees is safety, this inevitably includes component reliability issues. PWGI is concerned with operating experience. It is concerned mainly with the analysis of safety significant incidents, but it undertakes special studies as well. In the area of reliability it has issued a report on the evidence of ageing effects on certain safety-related components. PWGS has activities in fracture mechanics, non-destructive examination and material degradation, as being the three aspects of structural integrity for metal reactor components. It has recently widened its scope to include the ageing of concrete structures and the seismic behaviour of structures. In the area of component reliability, it has organised workshops on pipe leak and break probabilities, and on probabilistic structural integrity analysis. PWG5 considers risk assessment, and as part of this considers the collection of reliability data. It has organised a questionnaire and has held two workshops covering the issue of data collection. This paper provides background on the Agency itself, while focusing on the component reliability activities within NEA carried out mainly through the Committee on the Safety of Nuclear Installations and the groups of technical experts on operating experience, structural integrity, and risk assessment. Principal Working Groups Nos. 1, 3 and 5.