What does the term “boiling liquid expanding vapor explosion (BLEVE)” refer to?

The term "boiling liquid expanding vapor explosion (BLEVE)" specifically refers to a scenario where a vessel containing a liquefied gas is subjected to heat. This results in the liquid boiling and generating vapor at an increasing pressure. When the pressure exceeds the strength of the containment vessel, it leads to a catastrophic rupture.

When this rupture occurs, the superheated liquid rapidly vaporizes and expands, resulting in a violent explosion. This phenomenon is particularly dangerous because it can lead to both an explosive release of energy and a dispersal of the liquid that can ignite if the conditions are right.

In contrast, the other options describe different types of incidents: a sudden release of pressure can happen in various situations but isn't specific to the BLEVE context, an explosion from a violent chemical reaction pertains to chemical reactivity rather than physical state changes of a liquid, and combustion in open air relates to fires rather than the confined but heated conditions leading to a BLEVE.