Systems AnalysisPrograms for Hands-on Integrated Reliability Evaluations (SAPHIRE): Technical Reference (NUREG/CR-6952, Volume 2)

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Publication Information

Manuscript Completed: October 2007
Date Published: September 2008

Prepared by:
C. L. Smith, S.T. Wood, W.J. Galyean, J.A. Schroeder
S.T. Beck, M.B. Sattison

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

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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 (PC) running the Microsoft Windows™ operating system. Herein information is provided on the principles used in the construction and operation of Version 6.0 and 7.0 of the SAPHIRE system. This report summarizes the fundamental mathematical concepts of sets and logic, fault trees, and probability. This volume then describes the algorithms used to construct a fault tree and to obtain the minimal cut sets. It gives the formulas used to obtain the probability of the top event from the minimal cut sets, and the formulas for probabilities that apply for various assumptions concerning reparability and mission time. It defines the measures of basic event importance that SAPHIRE can calculate. This volume gives an overview of uncertainty analysis using simple Monte Carlo sampling or Latin Hypercube sampling, and states the algorithms used by this program to generate random basic event probabilities from various distributions. Also covered are enhance capabilities such as seismic analysis, cut set "recovery," end state manipulation, and use of "compound events."

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