A BLEVE is best described as

• A. A large chemical burn
• B. A slow venting of vapor
• C. A rapid pressure increase in a confined vessel that results in a sudden release of pressure as the vessel ruptures
• D. An explosive gas mixture with no pressure change

Answer: (C)

A BLEVE occurs when a container holding a pressurized, heated liquid is forced to fail. The liquid inside boils and builds very high pressure while the vessel remains intact, so the vessel is driven toward rupture. When the container finally gives way, all that stored energy—high-pressure vapor and boiling liquid—escapes rapidly, creating a violent release that can be explosive and often accompanied by a fireball. This describes a rapid pressure increase in a confined vessel that results in a sudden release of pressure as the vessel ruptures, which is exactly what the option states. The other descriptions miss the mechanism: a chemical burn implies a reaction on contact rather than internal pressure buildup; slow venting describes a gradual release, not a catastrophic rupture; and an explosive gas mixture with no pressure change ignores the critical buildup and sudden rupture that define a BLEVE.