Decompression theory

Decompression theory is the study and modelling of how the inert gas component of a breathing gas moves from the lungs into body tissues and back out again as a person is exposed to changes in ambient pressure, most importantly during underwater diving and compressed air work but also affecting astronauts, high altitude mountaineers and aircraft passengers exposed to reduced pressure. Gas is taken up and released from tissues in dissolved form, but if pressure is reduced too quickly, dissolved gas can form bubbles in the tissues, causing damage and decompression sickness while also slowing further gas elimination. Decompression models, both deterministic and probabilistic, attempt to predict how gas is eliminated and when bubbles are likely to form, with the aim of producing decompression procedures that are both acceptably safe and practical, generally by ascending fast enough to maintain a strong gradient for gas elimination without provoking symptomatic bubble formation.