Modeling Characteristics of an Operational Probabilistic Safety Assessment (PSA)

Conference · Mon Jul 01 04:00:00 EDT 2002

OSTI ID:21070077

Anoba, Richard C ^[1]; Khalil, Yehia ^[2]; Fluehr, III, J J; Kellogg, Richard; Hackerott, Alan ^[3]

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1. Anoba Consulting Services LLC, 36 Solitude Way, Wilmington, Delaware 19808-2029 (United States)
2. Dominion Nuclear Connecticut, Rope Ferry Road Waterford, CT 06385 (United States)
3. Omaha Public Power District, 444 S. 16th St. Mall Omaha, NE 68102-2247 (United States)

Probabilistic Safety Assessments (PSAs) are increasingly being used as a tool for supporting the acceptability of design, procurement, construction, operation, and maintenance activities at nuclear power plants. Since the issuance of Generic Letter 88-20 and subsequent Individual Plant Examinations (IPEs)/Individual Plant Examinations for External Events (IPEEEs), the NRC has issued several Regulatory Guides such as RG 1.182 to describe the use of PSA in risk informed regulation activities. The PSA models developed for the IPEs were typically based on a 'snapshot' of the the risk profile at the nuclear power plant. The IPE models contain implicit assumptions and simplifications that limit the ability to realistically assess current issues. For example, IPE modeling assumptions related to plant configuration limit the ability to perform online equipment out-of-service assessments. The lack of model symmetry results in skewed risk results. IPE model simplifications related to initiating events have resulted in non-conservative estimates of risk impacts when equipment is removed from service. The IPE models also do not explicitly address all external events that are potentially risk significant as equipment is removed from service. (authors)

• Research Organization: The ASME Foundation, Inc., Three Park Avenue, New York, NY 10016-5990 (United States)
• OSTI ID: 21070077
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
DESIGN
HAZARDS
MAINTENANCE
NUCLEAR POWER PLANTS
PROBABILISTIC ESTIMATION
PROCUREMENT
REACTOR OPERATION
REGULATIONS
REGULATORY GUIDES
RISK ASSESSMENT
SIMULATION