What is the primary concern when dealing with pressurized cylinders in a fire situation?

The primary concern when dealing with pressurized cylinders in a fire situation is the potential for a BLEVE, or Boiling Liquid Expanding Vapor Explosion. This phenomenon occurs when a pressurized cylinder becomes heated, leading to an increase in the temperature and pressure of the contents. If the heat continues unchecked, the cylinder can rupture violently, resulting in an explosive release of gas and a significant fireball.

BLEVE is particularly dangerous because the explosion can propel the cylinder over a distance, posing risks to life and property far beyond the immediate area of the fire. Addressing this risk involves several considerations, including cooling the cylinder to prevent overheating, maintaining a safe distance, and establishing exclusion zones.

The effectiveness of firefighting efforts and safety measures generally hinges on understanding and mitigating this risk, making it a paramount concern in emergency response scenarios involving pressurized cylinders.