🔥 SELF-CONTAINED BREATHING APPARATUS (SCBA) • A Self-Contained Breathing Apparatus permits firefighters to operate safely in atmospheres that cannot support life, including: – Immediately Dangerous to Life and Health (IDLH) conditions – Oxygen-deficient atmospheres (below 19.5% O₂) – Smoke-filled, toxic, superheated, or contaminated air • SCBA is also used when the air is unsafe, irritating, or uncomfortable (heat, smoke, particulates, off-gassing chemicals). ⸻ Composition of SCBA Air Compresse