Fuzzy LOPA for the evaluation of accident scenarios and risk reduction measures in suppler manner

Abstract

The analysis and evaluation of risks by the LOPA method requires the presence of certain data and information on the various risk evaluation parameters such as, the frequencies of initiating events, the probabilities failures of the security barriers and also probability of ignition .This data is generally obtained from the history of the system analyzed. In the absence or lack of data on the state of the system, other sources such as databases and expert judgment are used. Despite the fact that the choice of data is made while respecting the adaptation of this data to the system studied, based on its history and on similar systems having the same mode of operation, it seems important to emphasize the fact that imperfections are not properly taken into account. Linked to the data used by the various risk analysis methods including the LOPA method, the results are always uncertain and imprecise. To address such a problem, we use the "fuzzy LOPA" approach. As a case study, we used an operational industrial system which is a heater H-101.