Fire as a primary event of accident domino sequences: The case of BLEVE

• Fire is the prevailing first event in BLEVE domino accidents.
• With flames engulfment or impingement on a vessel, a BLEVE can occur at any moment.
• In BLEVE accidents, TTF can vary from less than 1 min to more than 1 h.
• Fireproofing and PSV can increase TTF but do not guarantee avoiding the BLEVE.

The domino sequences found in major accidents have been analyzed for a large set of cases (330); the first event triggering the domino effect was an explosion or a fire, both with approximately the same contribution; the same proportion has been found when all domino effect steps were considered. Although fire effects usually reach a distance much shorter than those of an explosion, as fire is the most frequent major accident it is often found as the first step of domino sequences. This is especially true in the case of BLEVEs. Both in fixed plants and in the transportation of hazardous materials, in the event of a fire, if flames affect a vessel and the fireproofing layer has been damaged, a BLEVE can occur at any moment. 127 BLEVE accidents involving domino effect have been analyzed. It has been found that fire is significantly more frequent than explosion, both in triggering the domino effect sequence and in intermediate steps. The time to failure can range from 1 min or even less up to several hours, an aspect that should be very important for the management of the emergency. A set of conclusions are inferred from this survey.