Heat does not have to be present for a BLEVE to occur. If the vessel contains non-flammable liquid (such as a steam boiler), a BLEVE will occur, but the vapors will not ignite.
Whether or not a fire occurs is contingent on if the liquid inside of the tank is flammable. If the vessel can no longer contain the pressure inside of the sealed tank due to the high temperatures, it will mechanically fail, causing the explosion. Hazmat basics: 10 straightforward answers for firefighter responseĪ BLEVE is a boiling liquid expanding vapor explosion, which occurs when the pressurized liquid inside a vessel, such as a propane tank, reaches temperatures higher than that liquid’s boiling point.