Saturation diving is a deep-sea diving specialty that is like no other. It involves living and working deep below the surface for weeks at a time.
Saturation diving, also called Sat diving, is a diving technique that minimizes the risk of decompression sickness. With Sat diving , the diver's blood stream and tissues are saturated with helium or other suitable gas at the pressure of the surrounding water. Because the diver's blood and bodily tissues are saturated at the pressure of the surrounding water, there is no need to decompress between dives allowing a diver to dive in shifts that span for weeks with only needing to decompress one time for the entire tour of duty, which usually lasts for weeks.
“Saturation” refers to the fact that the diver's tissues have absorbed the maximum partial pressure of gas possible for that depth due to the diver being exposed to breathing gas at that pressure for prolonged periods. This is significant because once the tissues become saturated, the time to ascend from depth, to decompress safely, will not increase with further exposure.
In saturation diving, the divers live in a pressurized environment, which can be a saturation system or “saturation spread”, a hyperbaric environment on the surface, or an ambient pressure underwater habitat. This may be maintained for up to several weeks, and they are decompressed to surface pressure only once, at the end of their tour of duty. By limiting the number of decompressions in this way, the risk of decompression sickness is significantly reduced.