A Cause-Defense Approach to the Understanding and Analysis of Common Cause Failures

Technical Report · Thu Mar 01 00:00:00 EST 1990

DOI:https://doi.org/10.2172/6976104· OSTI ID:6976104

Paula, Henrique M. ^[1]; Campbell, David J. ^[1]; Parry, Gareth W. ^[2]; Mitchell, Donald B. ^[3]; Rasmuson, Dale M. ^[4]

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1. JBF Associates, Knoxville, TN (United States)
2. NUS Corp., Gaithersburg, MD (United States)
3. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
4. US Nuclear Regulatory Commission (NRC), Washington, DC (United States). Div. of Systems Research

For improved reliability and safety, nuclear power plants are designed with redundant safety systems, many of which also have redundant trains of equipment within the system. However, the very high reliability theoretically achievable through the use of redundancy is often compromised by single events that can individually render redundant components unavailable (common cause failure (CCF) events). As evidenced by the results of probabilistic risk assessments (PRAs) and by historical experience with nuclear power plant operations, CCF events are usually major contributors to the risk posed by nuclear power plant operation. Thus, it is important that PRAs recognize the potential for CCF events and realistically account for CCF contributions to system unavailability and plant risk. Much progress has been made over the years in the area of CCF analysis, including the development of both qualitative analysis methods. Until now, however, CCF methodologies have not explicitly and systematically accounted for the impact of plant-specific defenses, such as design features and operational and maintenance policies, in place to reduce the likelihood of failure occurrences at nuclear power plants. Recognizing the importance of this issue, the NRC has funded a research effort that has focused on developing the cause-defense methodology for CCF analysis and prevention. This report presents the results of this research. Specifically, this report discusses the development of (1) procedures for identifying the potential for CCF events at individual nuclear power plants and (2) cause-defense matrices for analysis of CCF events. Also, new concepts and more precise definitions are introduced to enhance CCF terminology and interpretation of historical event data. Contains 35 refs., 8 figs., 32 tabs.

• Research Organization: US Nuclear Regulatory Commission (NRC), Washington, DC (United States). Div. of Systems Research; Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); JBF Associates, Knoxville, TN (United States); NUS Corp., Gaithersburg, MD (United States)
• Sponsoring Organization: USNRC
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 6976104
• Report Number(s): NUREG/CR-5460; SAND-89-2368; ON: TI90009346
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
NUCLEAR POWER PLANTS
FAILURE MODE ANALYSIS
DOCUMENTATION
INSPECTION
MATHEMATICAL MODELS
MEASURING METHODS
QUALITY CONTROL
REACTOR COMPONENTS
REACTOR MAINTENANCE
REACTOR OPERATION
REACTOR SAFETY
RISK ASSESSMENT
STRUCTURAL MODELS
SURVEILLANCE
TECHNOLOGY ASSESSMENT
CONTROL
MAINTENANCE
NUCLEAR FACILITIES
OPERATION
POWER PLANTS
SAFETY
SYSTEM FAILURE ANALYSIS
SYSTEMS ANALYSIS
THERMAL POWER PLANTS
220900* - Nuclear Reactor Technology- Reactor Safety
210000 - Nuclear Power Plants