Which scenario best describes BLEVE?

• A. Rapid vaporization of a liquid stored under pressure upon release to the atmosphere following major vessel failure due to external heat, leading to an explosion into multiple pieces.
• B. Slow emission of steam from a vent.
• C. A pure hydrocarbon ignition from a static spark.
• D. Foam system failure during operation.

Answer: (A)

BLEVE stands for Boiling Liquid Expanding Vapor Explosion. It occurs when a container holding a liquid at high pressure or elevated temperature is heated by a fire, causing the liquid to flash boil inside the vessel. If the vessel ruptures, the sudden release of pressure and rapid vaporization of the liquid expands violently, producing an explosion and often shattering the container. The scenario describes this exact sequence: a liquid stored under pressure is released after the vessel fails due to external heat, leading to rapid vaporization and an explosion into multiple pieces. It’s not just a slow steam vent, nor ignition from a static spark, nor foam system failure.