Optimal test interval modeling of the nuclear safety system using the inherent unavailability and human error

Abstract

In the current system availability analysis, a system is assumed to return to an as-good-as-new state after test or repair by considering the human error and the unavailability on demand. But a synthetic modeling approach has not been adequately developed for a redundant system. In this paper, constant unavailability due to human error and inherent unavailability, caused by inherent undetectability is introduced for a system optimal test interval analysis. Constant unavailability, makes it possible to determine a rational optimal test interval for a redundant component system. The results show that the optimal test interval in a redundant component system mainly depends on the constant unavailability. A practical test interval of a redundant system can be obtained with the modeling used in the present analysis.