Development of a new quantification method for a fire PSA

Abstract

For an internal fire analysis, fire scenarios are developed carefully and quantified in a sequential and iterative way in a traditional fire Probabilistic Safety Assessment (PSA). However, there has been no proven explicit method to avoid these iterative quantifications till now. This study presents the Jung's Single Top And Run (JSTAR) method that facilitates a simultaneous single quantification of all fire scenarios. The JSTAR method could be employed at the fire PSA phases of a quantitative screening or detailed analysis. Using the JSTAR method, accurate fire risks of a fault tree that has many negates could be calculated by avoiding the frequent house event propagations of the fire scenario conditions. Furthermore, the proposed JSTAR method is a simple and explicit method to build a single-top external event PSA model for a risk-monitoring system. The JSTAR method could be implemented easily by developing a small automatic conversion tool. Depending on the maintenance policy of a fire PSA model, a single-top fire PSA model that is created by the conversion tool could be maintained permanently or it could be temporarily generated and discarded. The use of the JSTAR method is recommended for all external event PSAs such as an internal flooding risk analysis.