A
self-contained breathing apparatus, or
SCBA, sometimes referred to as a
compressed air breathing apparatus (CABA), or simply
breathing apparatus (BA), is a device worn by
rescue workers,
firefighters, and others to provide breathable air in an "Immediately Dangerous to Life or Health" atmosphere (
IDLH). When not used underwater, they are sometimes called
industrial breathing sets. The term "self-contained" means that the breathing set is not dependent on a remote supply (e.g., through a long hose). If designed for use under water, it is called
SCUBA (self-contained
underwater breathing apparatus).