When a firefighter's low pressure alarm sounds, what percentage of air is left in the tank?

The low pressure alarm on a firefighter's SCBA (Self-Contained Breathing Apparatus) is designed to alert the firefighter when the air supply in the tank is nearing depletion. In many SCBA systems, the low pressure alarm generally activates when there is approximately 25% of the total air supply remaining in the tank. This is a critical safety feature intended to give firefighters ample warning to exit hazardous environments before their air supply is critically low.

This percentage is based on standard operating procedures within the firefighting community, ensuring that firefighters can monitor their air supply effectively and make safe decisions during operations. Understanding this function emphasizes the importance of situational awareness and managing resources while working in potentially dangerous situations.