A breathing gas is a mixture of gaseous chemical elements and compounds used for respiration. Air is the most common and only natural breathing gas, but...

Trimix is a breathing gas consisting of oxygen, helium and nitrogen and is used in deep commercial diving, during the deep phase of dives carried out...

surface-supplied diving is that breathing gas is supplied from the surface, either from a specialised diving compressor, high-pressure gas storage cylinders, or...

occupant. Breathing apparatus may be classified by type in several ways: by breathing gas source: self-contained gas supply, remotely supplied gas, or purified...

equilibrium with the partial pressures of the inert components of the breathing gas used. It is a diving mode that reduces the number of decompressions...

Hydrox, a gas mixture of hydrogen and oxygen, is occasionally used as an experimental breathing gas in very deep diving. It allows divers to descend several...

open-circuit breathing apparatus, where the exhaled gas is discharged directly into the environment. The purpose is to extend the breathing endurance of...

just scuba, is any breathing apparatus that is entirely carried by an underwater diver and provides the diver with breathing gas at the ambient pressure...

Work of breathing (WOB) is the energy expended to inhale and exhale a breathing gas. It is usually expressed as work per unit volume, for example, joules/litre...

underwater diving whereby divers use breathing equipment that is completely independent of a surface breathing gas supply, and therefore has a limited...