Immediately prior to donning SCBA, firefighters should:

Before donning a Self-Contained Breathing Apparatus (SCBA), it is essential for firefighters to check the cylinder gauge to ensure the cylinder is full. This step is crucial because the effectiveness of the SCBA relies on having a sufficient air supply for the duration of the firefighting operation. A full cylinder guarantees that the firefighter can operate safely in environments that may be oxygen-deficient or filled with harmful smoke and gases.

Ensuring that the SCBA is fully charged helps to minimize risks during an emergency response. If the cylinder is not full, it may lead to an early air supply depletion, endangering the firefighter's safety and potentially compromising the incident response. This practice aligns with standard operating procedures to check equipment readiness before use.

Other actions, such as removing gloves, securing helmets, or performing a safety brief, are important in their own right, but they do not carry the same level of immediate impact on the firefighter's safety regarding respiratory protection. The priority in this instance is confirming the air supply is adequate for operation.