Which factor is most commonly cited as the cause of a BLEVE?

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Multiple Choice

Which factor is most commonly cited as the cause of a BLEVE?

When a vessel holding a liquid under pressure is heated, the liquid wants to boil and expand. If there isn’t enough vapor space inside, the expanding gas and liquid increase the internal pressure until the tank fails catastrophically, producing a BLEVE. The most commonly cited cause is overfilling the tank, which leaves little headspace for the vapor to occupy as it heats, so the pressure rises rapidly and the vessel can rupture violently. Relief devices help by venting excess pressure, which is why their activation would reduce BLEVE risk. Cooling the upper portions with water is a firefighting measure to slow heat input and prevent rapid pressure rise. Flames contacting the tank shell adds heat and can contribute to the problem, but it isn’t the primary, most-cited cause.

When a vessel holding a liquid under pressure is heated, the liquid wants to boil and expand. If there isn’t enough vapor space inside, the expanding gas and liquid increase the internal pressure until the tank fails catastrophically, producing a BLEVE. The most commonly cited cause is overfilling the tank, which leaves little headspace for the vapor to occupy as it heats, so the pressure rises rapidly and the vessel can rupture violently.

Relief devices help by venting excess pressure, which is why their activation would reduce BLEVE risk. Cooling the upper portions with water is a firefighting measure to slow heat input and prevent rapid pressure rise. Flames contacting the tank shell adds heat and can contribute to the problem, but it isn’t the primary, most-cited cause.

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