Uncontrolled Decompression

Uncontrolled decompression is an unplanned drop in the pressure of a sealed system, such as an aircraft cabin, and typically results from human error, material fatigue, engineering failure, or impact, causing a pressure vessel to vent into its lower-pressure surroundings or fail to pressurize at all.

Such decompression may be classed as Explosive, Rapid or Slow:

• Explosive decompression (ED) is violent, the decompression being too fast for air to safely escape from the lungs.
• Rapid decompression, while still fast, is slow enough to allow the lungs to vent.
• Slow or gradual decompression occurs so slowly that it may not be sensed before hypoxia sets in.