A brief introduction to decompression chambers for diving.

A decompression chamber (or pressure chamber) is an essential piece of equipment that helps divers perform saturation diving, and it also serves as a crucial treatment for decompression sickness. When divers descend to great depths, they may suffer from decompression sickness—commonly known as "diver's disease" or "caisson disease"—due to changes in pressure. This condition typically arises when the ambient pressure around the body drops rapidly, causing the body’s tissues to become saturated with nitrogen. Decompression sickness is both a diving hazard and a barotrauma. Below, we’ll briefly introduce how a decompression chamber works.

According to Henry's law, when the pressure of a gas above a liquid decreases, the amount of gas dissolved in the liquid also decreases. An example that illustrates this law is when you open a bottle or can of soft drink—gas immediately escapes from it, and bubbles appear in the liquid. This release of carbon dioxide occurs because the pressure inside the container drops to atmospheric pressure.

The function of a decompression chamber for scuba diving is similar to that of... The “opened cola” is repressurized to prevent bubble formation, and then slowly depressurized within a safe range without generating excessive bubbles, allowing the gas to escape gradually.

To ensure safe diving, it is essential to control the ascent rate, ascend slowly, and allow sufficient time for the body to eliminate gases, thereby reducing the risk of decompression sickness. Diving decompression chambers are typically used for dives exceeding the no-decompression limits. A 40-meter dive may require decompression times that far exceed the actual duration of the dive itself. A dive lasting more than ten minutes at a depth of 100 meters could necessitate decompression periods lasting up to six hours.

In saturation diving, divers remain in a high-pressure environment for extended periods, during which the inert gas components in the breathing gases absorbed by various tissues throughout the body reach a state of complete saturation. Between successive dives, divers must remain in the same high-pressure environment. A decompression chamber (or pressurized chamber) can provide them with both a high-pressure working environment and living quarters. Before completing all underwater operations, divers are allowed to perform only one decompression procedure.