Common-cause-failure (CCF) events can significantly impact the availability of safety systems of nuclear power plants. For this reason, the International Common Cause Failure Data Exchange (ICDE) project was initiated by several countries in 1994. In 1997, the Committee on the Safety of Nuclear Installations (CSNI) formally approved the carrying out of this project
within the OECD/NEA framework.
This report documents a study performed on a set of ICDE events related to switching devices and circuits breakers (CBs). The events studied here had been collected in the ICDE database. Organisations from Canada, Finland, France, Germany, Spain, Sweden, United Kingdom and United States contributed to the exchange. The ICDE Project is unique in that it collects and analyses large amounts of data from different countries to draw conclusions about common cause failures. One-hundred and four (104) ICDE events, exhibiting at least some degree of dependency, and spanning a period from 1983 through 2004, were examined in the study.