Decompression

Decompression is the reduction of surrounding pressure or the release of dissolved gases from a material, most commonly discussed in contexts involving high-pressure environments such as diving, aviation, and spaceflight. In biological systems, rapid pressure change can cause gases dissolved under pressure to come out of solution and form bubbles.

In diving, the body absorbs gases, primarily nitrogen, at depth. When a diver ascends, the reduced pressure can cause dissolved nitrogen to form bubbles in tissues and blood, leading to decompression sickness and, in severe cases, arterial gas embolism. Symptoms can include joint and muscle pain, dizziness, fatigue, skin changes, numbness, and cognitive or motor impairment. Risk factors include excessive depth or bottom time, rapid ascent, inadequate decompression stops, dehydration, and individual susceptibility.

Prevention centers on controlled decompression during ascent. This includes following established dive tables or dive computer profiles, performing staged decompression or safety stops, using appropriate breathing gases, and avoiding rapid ascents. Similar pressure-change risks occur in unpressurized or high-altitude aviation and spaceflight; cabin pressurization and supplemental oxygen help mitigate these risks.

Treatment for decompression-related conditions involves prompt hyperbaric recompression therapy to reduce bubble size and improve tissue oxygenation, typically accompanied by 100% oxygen and supportive medical care. Early recognition and treatment improve outcomes and reduce complications.

Outside physiological contexts, decompression also refers to relieving pressure in engineering systems and to restoring data from compressed form in computing. In computing, decompression reconstructs original data using algorithms such as Huffman coding or LZ77, enabling storage or transmission efficiency gains to be realized.