A type of respiratory protective device that supplies clean, compressed air to the user from an independent air cylinder. SCBAs are used in hazardous environments with oxygen deficiency or high levels of airborne contaminants, such as firefighting, confined space entry, and HAZMAT operations.
SCBAs are classified as:
Open-Circuit SCBA: Uses a compressed air cylinder and releases exhaled air into the environment. Commonly used in firefighting (NIOSH and NFPA 1981 compliant).
Closed-Circuit SCBA (Rebreather): Recirculates exhaled air after CO₂ scrubbing and oxygen replenishment, extending usage time (used in deep-sea diving and industrial applications).
SCBAs must meet certification standards such as NFPA 1981 (firefighting), EN 137 (European industrial use), and ISO 23269 (marine safety).