Proceedings of the ICDE workshop on qualitative and quantitative use of ICDE data

Common-cause-failure (CCF) events can significantly impact the availability of safety systems of nuclear power plants. In recognition of this, CCF data are systematically being collected and analysed in several countries, e.g. in Germany, France, Sweden and the United States A serious obstacle to the use of national qualitative and quantitative data collections by other countries is that the criteria and interpretations applied in the collection and analysis of events and data differ among the various countries. A further impediment is that descriptions of reported events and their root causes, which are important to the assessment of the events, are usually written in the native language of the countries where the events were observed. Preparation for ICDE project was initiated in August of 1994. Swedish and US Nuclear Power Inspectorates (SKI and NRC) identified the need to establish an international project aiming at collection and analysis of CCF data for key components of the main safety systems at for world's nuclear power plants and further exchange of these data between participating countries. Since April 1998, the OECD/NEA has formally operated the project. The Phase II with an agreement period 2000-2002 will be continued with a new phase. The agreement for the phase III covers the period 2002-2005. As for the end of phase II data collection, analysis and exchange have been performed for centrifugal pumps, diesel generators, motor-operated valves, safety and relief valves, check valves and batteries. Final reports for centrifugal pump, diesel generators motor-operated valves and safety relief valves have been developed. Member countries, which formed the ICDE Working Group under the Phase II Agreement of OECD/NEA and the organisations representing them in the project group, were as of 2001: Canada - AECB, Finland - STUK, France - IPSN, Germany - GRS, Spain - CSN, Sweden - SKI, Switzerland - HSK, United Kingdom - NII, United States - NRC. The objective with the ICDE activity is to provide a framework for a multinational co-operation in order to: - generate qualitative insights on root causes of CCF events that can be used to derive provisions for preventing CCF events, or for mitigating their consequences, should they occur; - establish an international working group on a long term basis which will collect and analyse CCF events; - generate the framework for efficient experience feedback on CCF phenomena and on defence against CCF. Closely related to the ICDE project, a workshop was organised by the Committee on the Safety of Nuclear Installations (CSNI) of the OECD Nuclear Energy Agency (NEA) in June 2001 in Stockholm. The idea was to discuss the qualitative and quantitative insights gained in collecting and using CCF data. The workshop was hosted by the Swedish Nuclear Power Inspectorate SKI, and it gathered a large audience of researchers, regulators and industry representatives. The findings of the discussions and the papers of the workshop are presented in these proceedings