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SAPHIRE is a probabilistic risk and reliability assessment software tool. SAPHIRE stands for Systems Analysis Programs for Hands-on Integrated Reliability Evaluations. The system was developed by the U.S. Nuclear Regulatory Commission (NRC)

Development began in the mid-1980s when the NRC began exploring two notions: 1) that probabilistic risk assessment (PRA) information could be displayed and manipulated using the emerging microcomputer technology of the day and 2) the rapid advancement of PRA technology required a relatively inexpensive and readily available platform for teaching PRA concepts to students.

The history of SAPHIRE:

1987 Version 1 of the code called IRRAS (now known as SAPHIRE) introduced an innovative way to draw, edit, and analyze graphical fault trees.

1989 Version 2 is released incorporating the ability to draw, edit, and analyze graphical event trees.

1990 Analysis improvements to IRRAS led to the release of Version 4 and the formation of the IRRAS Users Group.

1992 Creation of 32-bit IRRAS, Version 5, resulted in an order-of-magnitude decrease in analysis time. New features included: end state analysis; fire, flood, and seismic modules; rule-base cut set processing; and rule-based fault tree to event tree linking.

1997 SAPHIRE for Windows, version 6.x, is released. Use of a Windows user-inferface makes SAPHIRE easy to learn. The new "plug-in" feature allows analysts to expand on the built-in probability calculations.

1999 SAPHIRE for Windows, version 7.x, is released. Enhancements are made to the event tree "linking rules" and to the use of dual language capability inside the SAPHIRE database.