A self-contained breathing apparatus (SCBA) contains a face mask, air source, pressure regulator, and a carrying harness

 A self-contained breathing apparatus (SCBA) contains a face mask, air source, pressure regulator, and a carrying harness. 

Components

Face mask: A mouthpiece, half mask, or full-face mask that's connected to air supply pipes 

Air source: A tank of compressed air, compressed oxygen, or an oxygen-generating chemical 

Pressure regulator: Regulates the air pressure from the tank 

Carrying harness: A framed harness that holds the air cylinders on the user's back 

Air cylinders: One or two high-pressure tanks that store compressed air or oxygen 

How it works

The components of an SCBA work together to provide a continuous supply of clean air to the user. The SCBA's protective hood covers the user's face and has an eye-covering visor that allows the user to see. 

SCBA use

SCBAs are used by people who work in environments where they need to breathe clean air, such as in firefighting and other high-risk situations