The SCBA air cylinder has a capacity of how many cubic feet?

The correct choice identifies that the SCBA (Self-Contained Breathing Apparatus) air cylinder has a capacity of 66 cubic feet. This capacity is significant as it determines the duration for which the firefighter can operate while using the SCBA under various conditions.

Having a cylinder capacity of 66 cubic feet allows a firefighter to have a sufficient air supply for a certain period, which is crucial during fire emergencies where access to breathable air is compromised. Firefighters rely on this specific air volume to perform their duties effectively and safely, particularly in hazardous environments where smoke and toxic fumes are present.

The other options may reflect various sizes of air cylinders that are not typically used in standard SCBA configurations for firefighting and rescue operations. Understanding the specifications of SCBA equipment, such as the air cylinder capacity, is essential for ensuring the safety and efficiency of firefighting tasks.