Systems AnalysisPrograms for Hands-on Integrated Reliability Evaluations (SAPHIRE): GEM Manual (NUREG/CR-6952, Volume 5)

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Publication Information

Manuscript Completed: October 2007
Date Published:
September 2008

Prepared by:
C.L. Smith, J. Schroeder, S.T. Beck

Idaho National Laboratory
Battelle Energy Alliance
Idaho Falls, ID 83415

D. O'Neal, NRC Project Manager

Prepared for:
Office of Nuclear Regulatory Research
U. S. Nuclear Regulatory Commission
Washington, DC 20555-0001

NRC Job Code N6203

Availability Notice


The Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) is a software application developed for performing a complete probabilistic risk assessment (PRA) using a personal computer running the Microsoft Windows™ operating system. SAPHIRE is primarily funded by the U.S. Nuclear Regulatory Commission (NRC) and developed by the Idaho National Laboratory (INL). The INL's primary role in this project is that of software developer and tester. Using the SAPHIRE analysis engine and relational database is a complementary program called GEM. GEM has been designed to simplify using existing PRA analysis for activities such as the NRC's Accident Sequence Precursor program. In this report, the theoretical framework behind GEM-type calculations are discussed in addition to providing guidance and examples for performing evaluations when using the GEM software. As part of this analysis framework, the two types of GEM analysis are outlined, specifically initiating event (where an initiator occurs) and condition (where a component is failed for some length of time) assessments.

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