PRAAGE: an interactive IBM-PC code for unreliability/aging analysis

The purpose of the PRAAGE code is to investigate the effects of aging on nuclear power plant system reliability using component information as input. It uses probabilistic risk assessment (PRA) with aging analysis to project system unavailability into the future, or by turning off the aging, may be used as a convenient interactive unavailability model for studying system improvements. This computer program serves to assemble the parts of the Aging and Life Extension Assessment Program (ALEAP), consisting of aging results from Nuclear Plant Aging Research testing, aging parameters extracted from several data bases, and studies of generic applicability. ALEAP chose to demonstrate the methodology on a component cooling water (CCW) system which, from previous work, was known to be very important to safety. Indian Point 2 was selected as the demonstration plant because of familiarity with its PRA. The fault tree model of the CCW and the nonaged component failure rates were taken directly from the plant's PRA. These are used in a linear aging model developed by Vesely. The aging parameters used in PRAAGE were obtained from a literature review but will be replaced by more definitive parameters as they are developed