What is the realistic duration of an SCBA air supply compared to its rated duration?

The realistic duration of an SCBA (Self-Contained Breathing Apparatus) air supply is generally much shorter than its rated duration due to several factors that affect air consumption during firefighting operations. The rated duration is based on tests conducted under ideal conditions, such as a low level of exertion and at a constant flow rate.

In real-world scenarios, firefighters face high-stress environments, heavy physical exertion, and often work in extreme heat and difficult conditions. These factors can lead to increased breathing rates and greater air consumption, ultimately reducing the effective time that an SCBA can provide breathable air. Additionally, unforeseen circumstances, such as prolonged exertion or emergency situations, can further shorten the usable air supply.

Thus, while the manufacturer's rating provides a benchmark, the real-life experience often reveals that the actual duration of breathable air can be significantly less than what is indicated. Understanding this disparity is crucial for effective planning and safety during firefighting operations.