Layers of Protection Analysis Using Possibility Theory
نویسندگان
چکیده
An important issue faced by risk analysts is how to deal with uncertainties associated with accident scenarios. In industry, one often uses single values derived from historical data or literature to estimate events probability or their frequency. However, both dynamic environments of systems and the need to consider rare component failures may make unrealistic this kind of data. In this paper, uncertainty encountered in Layers Of Protection Analysis (LOPA) is considered in the framework of possibility theory. Data provided by reliability databases and/or experts judgments are represented by fuzzy quantities (possibilit ies). The fuzzy outcome frequency is calculated by extended multip licat ion using αcuts method. The fuzzy outcome is compared to a scenario risk tolerance criteria and the required reduction is obtained by resolving a possibilistic decision-making problem under necessity constraint. In order to validate the proposed model, a case study concerning the protection layers of an operational heater is carried out.
منابع مشابه
جدول ارزیابی ایمنی مخازن شارژ آمونیاک با استفاده از روش آنالیز لایههای حفاظتی فازی
Introduction: Risk assessment of hazardous processes is the priority of risk management. Layer of protection analysis (LOPA) is one of the most popular methods used for risk assessment. Due to the insufficient information or uncertainty in failure rates (PFD) of protective layers, risk assessment based on the conventional LOPA can result in error in calculations. In this study, we tried to use ...
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