Oxygen window in diving decompression

Oxygen window in diving decompression refers to the physiological phenomenon that allows divers to safely ascend from depth without suffering from decompression sickness. This concept is a crucial part of decompression theory and practice, and is used in the planning and execution of decompression stops during a dive.

Physiology

The oxygen window is created by the difference in partial pressures of oxygen and nitrogen in the body. When a diver breathes air at depth, the increased pressure causes more nitrogen to dissolve in the body tissues. However, the body metabolizes oxygen at a constant rate, creating a "window" of pressure that is not filled by nitrogen. This window is the difference between the partial pressure of oxygen in the arterial blood and the oxygen pressure in the tissues.

Application in Diving

In diving decompression, the oxygen window is used to allow divers to ascend safely. By breathing pure oxygen at a decompression stop, the diver can increase the size of the oxygen window, allowing more nitrogen to be off-gassed from the tissues without increasing the risk of decompression sickness. This technique is commonly used in technical diving and commercial diving, where divers often spend extended periods at depth.

Decompression Models

Decompression models, such as the Bühlmann decompression algorithm, take the oxygen window into account when calculating decompression stops. These models use complex mathematical formulas to predict the rate of nitrogen off-gassing from the tissues, and adjust the length and depth of decompression stops accordingly.

Safety Considerations

While the oxygen window is a useful tool in decompression planning, it is not without risks. Breathing pure oxygen at depth can lead to oxygen toxicity, a potentially fatal condition. Therefore, divers must be properly trained in the use of oxygen in decompression and must monitor their oxygen exposure closely.

See Also

• Decompression (diving)
• Oxygen toxicity
• Technical diving