Which of the following describes a SCBA's full operational capacity?

The description of a SCBA's full operational capacity refers specifically to its ability to function effectively under high-pressure conditions. SCBAs, or Self-Contained Breathing Apparatus, are designed to provide breathable air to firefighters in environments that are immediately dangerous to life or health. The standard pressure at which many SCBAs operate is often around 4500 psi, with some newer models being capable of being pressurized up to 5500 psi. This higher pressure allows for a greater volume of air, extending the duration for which a firefighter can operate in hazardous conditions.

The capacity to filter air is not characteristic of SCBAs; instead, they supply clean, breathable air from a tank. While the effective operational time of 30 minutes is relevant, it is dependent on the pressure in the tank and the user's consumption rate rather than being a direct descriptor of capacity itself. Hence, the ability of a SCBA to be pressurized up to 5500 psi is a more accurate reflection of its operational capacity, reflecting its design to support long-duration use in emergencies.