A cascaded fuzzy-LOPA risk assessment model applied in natural gas industry

Natural gas plants demand high amount of energy provided through immense fuel gas units that may suffer risk hazards. Implementing a safety management system is the most efficient way of allocating resources for safety. This paper adopts The Layer of Protection Analysis (LOPA) risk Management associated with Fuzzy Logic methodology to prevent or limit industrial accidents. We provide an innovative cascaded fuzzy-LOPA model for certain hazardous scenarios and at different frequencies of occurrence. The introduced model is tested at moderate and high risk levels controlled in its practical limits through the use of Safety Integrity Functions (SIF). Obtained results show how this fuzzy-LOPA achieves better results to maintain the Safety Integrity Level (SIL) rating to acceptable limits.

► A cascaded fuzzy-layer of protection analysis (LOPA) model for SIL assessment was introduced.
► The model can be used to solve the problem of catastrophic failure in natural gas plants.
► The model has proven remarkable advantages in calculating the SIL rating for any SIF in an easy, inexpensive and time saving method.
► Fuzzy based models are reliable and could be readjusted to produce the most accurate and reliable results.