Which of the following should be checked regularly on an SCBA?

Regularly checking the tank pressure on a Self-Contained Breathing Apparatus (SCBA) is crucial for ensuring the safety of the firefighter. The tank pressure indicates how much breathable air is available to the user. Maintaining adequate pressure is vital because if the pressure drops below a certain threshold, the SCBA may not provide enough air during an emergency response, potentially leading to a life-threatening situation.

The SCBA needs to be functional and reliable, with the pressure gauge serving as a direct indicator of air availability. Firefighters must be familiar with the range of operating pressures, which allows them to monitor the air supply and replace or refill the tank as necessary before it becomes an issue.

The other options are also important components of SCBA maintenance but do not need to be checked as frequently as tank pressure. For instance, while air quality and oxygen concentration are crucial for the overall effectiveness of the SCBA and the health of firefighters, the pressure gauge provides immediate feedback on the operational readiness of the SCBA during use. Transformer function is not relevant to SCBA operation, making it less pertinent in this context.