Personal Protective Equipment and Self-Contained Breathing Apparatus
The ensemble
Structural firefighting PPE includes helmet with eye protection, hood, coat and pants with moisture barrier and thermal liner, gloves, and boots, tested to NFPA 1971; SCBA is tested to NFPA 1982. Know what each piece does: the moisture barrier stops liquids, the thermal liner insulates, the outer shell resists abrasion and flame. No PPE is a pass for entering an IDLH atmosphere - SCBA is mandatory there.
SCBA components and use
Identify cylinder (2216, 3000, or 4500 psi), regulator with bypass and purge, facepiece, harness with integrated PASS device, low-air alarm, and end-of-service-time indicator. The low-air alarm sounds around one-third of capacity remaining. The bypass is a last resort for regulator failure, not a way to stretch air. Cylinders require hydrostatic testing at intervals (commonly every five years for composite). Doffing and donning skills matter: the usual benchmark is one minute for the complete ensemble plus one minute for SCBA.
Air management and traps
A 30-minute-rated cylinder does not give 30 minutes of work - capacity is rated at a fixed breathing rate, and exertion, stress, and cold all increase consumption. Manage air with a point of no return based on task, exit distance, and team status. The classic traps: choosing to remove the facepiece for communication or comfort, misreading the low-air alarm as an equipment failure, and using the bypass to purge routinely. Facial hair that breaks the seal, and eyewear that interferes with the mask, are disqualifying.
Rule of thumb
Before entry, ask: is my air enough to reach the objective, complete the task, and exit with a reserve? If the reserve is in doubt, the answer is no.