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...

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...

Breathing (spiration or ventilation) is the rhythmical process of moving air into and out of the lungs to facilitate gas exchange with the internal environment...

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...

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...

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...

A self-contained breathing apparatus (SCBA) is a device worn to provide an autonomous supply of breathable gas in an atmosphere that is immediately dangerous...

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

by breathing gas source: self-contained gas supply, or remotely supplied gas, by breathing circuit type: open, semi-closed, or closed circuit, by gas supply...

due to external causes, when the breathing gas is hypoxic, or internal causes, such as reduced effectiveness of gas transfer in the lungs, reduced capacity...

allow the release of excess inert gases dissolved in their body tissues, which accommodated as a result of breathing at ambient pressures greater than...

sufficient breathing gas to safely return to a place where more breathing gas is available. In almost all cases this will be the surface. Gas planning includes...

odours from breathing gas. active addition System for semi-closed circuit rebreather feed gas addition in which gas is added to the breathing circuit by...

mix breathing gases for diving. gas blending Mixing breathing gases for diving, filling diving cylinders with gas mixes such as nitrox or trimix. gas block...

perfluorocarbon), rather than breathing air, by selecting a liquid that can hold a large amount of oxygen and is capable of CO2 gas exchange. This requires...

Diving rebreather technology may be used where breathing gas supply is limited, or where the breathing gas is specially enriched or contains expensive components...

diving is a mode of underwater diving using equipment supplied with breathing gas through a diver's umbilical from the surface, either from the shore...

single breathing hose from the mouthpiece to the scrubber and counterlung. Gas passes through it in both directions, unlike the one-way breathing loop configuration...

of a breathing gas Breathing gas switch – Changing between breathing gasses of different composition while diving Breathing loop – Breathing gas circuit...

underwater, both during breath-hold dives and while breathing at ambient pressure from a suitable breathing gas supply. It, therefore, includes the range of...

an underwater diver for use as an emergency supply of breathing gas in the event of a primary gas supply failure. A bailout cylinder may be carried by...

passages of a breathing apparatus in which the breathing gas flows in both directions as the user breathes in and out, causing the last exhaled gas to be immediately...

it is also used as a bailout gas. Helium is also useful as a breathing gas diluent to reduce work of breathing of gases, both at high ambient pressures...

gas oxygen supply, positive pressure demand apparatus, or constant flow apparatus using high pressure compressed air. Contamination of the breathing gas...

most common inert gas used in breathing gas for commercial diving is helium. Breathing gas – Gas used for human respiration Industrial gas – Gaseous materials...

water entry, descent, breathing underwater, monitoring the dive profile (depth, time, and decompression status), personal breathing gas management, situational...