[2D01-08] PRA Method 2

[2D01] Proposal to use a DQFM result to set a truncation value for minimal cutsets

*SHOTA SOGA¹, Eishiro Higo¹, Hiromichi Miura¹ (1. CRIEPI)

Keywords:Probabilistic Risk Assessment, DQFM method, Minimal cutset, Truncation value

In fault tree (FT) analysis, it is common to set a truncation value for minimal cut sets (MCS) evaluation to limit the number of generated MCSs. However, a truncation value is set in ad-hoc manner for each fault tree because it is not possible to obtain an appropriate truncation value prior to evaluation. This process is costly and needs to be improved because it is necessary to set a truncation value repeatedly until an appropriate truncation value is reached. In this study, we propose an approach to evaluate FTs and obtain truncation values using the Direct Quantification of a Fault tree Method (DQFM). In addition, a variance reduction method is considered to reduce the number of DQFM trials.