Dealing with uncertainty in effect analysis of test strategies on safety instrumented system performance

摘要

In this paper, we have attempted to show the effect of test strategies on the performance of safety instrumented system (SIS) in a fuzzy parameter environment. Two types of test strategies are considered: simultaneous and staggered tests. As a relevant parameters of SIS, common cause failure factor and diagnostic coverage (DC) rate are modeled by triangular fuzzy numbers and are injected into the fuzzy Markov model to calculate the fuzzy PFD of SIS. Sensitivity analysis is carried out to show the effect of fuzzy beta and DC variation on average fuzzy PFD of the SIS. An application case focused on a high integrity pressure protection system is carried out.