United States Nuclear Regulatory Commission - Protecting People and the Environment

International Common-Cause Failures

The purpose of the International Common-Cause Data Exchange (ICDE) Project is to allow multiple countries to collaborate and exchange Common-Cause Failure (CCF) data to enhance the quality of risk analyses that include CCF modeling. Because CCF events are typically rare events, most countries do not experience enough CCF events to perform meaningful analyses. Data combined from several countries, however, yields sufficient data for more rigorous analyses.

The objectives of the ICDE Project are the following:

  • To collect and analyze CCF events in the long term so as to better understand such events, their causes, and their prevention
  • To generate qualitative insights into the root causes of CCF events, which can then be used to derive approaches or mechanisms for their prevention or for mitigating their consequences
  • To establish a mechanism for the efficient feedback of experience gained on CCF phenomena, including the development of defenses against their occurrence, such as indicators for risk based inspections

The ICDE project participants developed the following coding guidelines:

The ICDE has issued CCF summary insight reports for the following equipment classes:

The qualitative insights gained from the analysis of CCF events are made available by reports that are distributed without restrictions. It is not the aim of those reports to provide direct access to the CCF raw data recorded in the ICDE databank. The confidentiality of the data is a prerequisite of operating the project. The ICDE database is accessible only to those members of the ICDE Project Working Group who have actually contributed data to the databank. Database requirements are specified by the members of the ICDE Project and are fixed in guidelines. Each member with an access to the ICDE database is free in using the collected data. It is assumed that the data will be used by the members in the context of PSA/PRA reviews and application.

Page Last Reviewed/Updated Thursday, July 21, 2016