Uncontrolled decompression

An uncontrolled decompression is an undesired drop in the pressure of a sealed system, such as a pressurised aircraft cabin or hyperbaric chamber, that typically results from human error, structural failure, or impact, causing the pressurised vessel to vent into its surroundings or fail to pressurize at all.

Such decompression may be classed as explosive, rapid, or slow:

• Explosive decompression (ED) is violent and too fast for air to escape safely from the lungs and other air-filled cavities in the body such as the sinuses and eustachian tubes, typically resulting in severe to fatal barotrauma.
• Rapid decompression may be slow enough to allow cavities to vent but may still cause serious barotrauma or discomfort.
• Slow or gradual decompression occurs so slowly that it may not be sensed before hypoxia sets in.