Frequency evaluation for domino scenarios triggered by heat radiation exposure

Severe fires may damage process equipment or pipes, leading to accident escalation and domino effect. Several accidents that occurred in the chemical and petrochemical industry presented these features. In order to account for these accident scenarios in conventional Quantitative Risk Analysis (QRA) studies, the more critical step is the availability of reliable models to estimate the probability of escalation given the fire impact mode on industrial equipment. The present contribution was aimed at developing a methodological approach to the assessment of the damage probability of process and storage vessels, identified as escalation targets, with the final aim of quantifying the frequency of accidents triggered by domino effect and the implementation in QRA studies. Efforts were devoted to include in the analysis relevant site-specific factors and to consider the presence of eventual mitigation measures. The developed methodology was applied to a case study dealing with the escalation of a primary fire scenario.