Saturation diving is diving for periods long enough to bring all tissues into 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 divers working at great depths must undergo by only decompressing divers once at the end of the diving operation, which may last days to weeks, having them remain under pressure for the whole period. A diver breathing pressurized gas accumulates dissolved inert gas used in the breathing mixture to dilute the oxygen to a non-toxic level in the tissues, which can cause decompression sickness if permitted to come out of solution within the body tissues; hence, returning to the surface safely requires lengthy decompression so that the inert gases can be eliminated via the lungs. Once the dissolved gases in a diver's tissues reach the saturation point, however, decompression time does not increase with further exposure, as no more inert gas is accumulated.
Saturation diver working on the USS Monitor wreck at 70 m (230 ft) depth.
Saturation diver conducts deep sea salvage operations.
Iremis da Vinci at the Albert Dock Basin, Port of Leith. A multi-purpose diving support vessel, built in the Republic of Korea in 2011, and registered at Majuro, Marshall Islands, it is 115.4m long and has a gross tonnage of 8691t.
Tektite I habitat
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 other mixtures of gases, or pure oxygen, are also used in breathing equipment and enclosed habitats. Oxygen is the essential component for any breathing gas. Breathing gases for hyperbaric use have been developed to improve on the performance of ordinary air by reducing the risk of decompression sickness, reducing the duration of decompression, reducing nitrogen narcosis or allowing safer deep diving.
Sailors check breathing devices at sea.
A closed bell used for saturation diving showing emergency gas supply cylinders
2% Heliox storage quad. 2% oxygen by volume is sufficient at pressures exceeding 90 msw.
Electro-galvanic fuel cell as used in a diving rebreather