Hyperbaric oxygen (HBO) therapy is performed in a hyperbaric chamber. The patient enters the chamber on a gurney, the door is closed and 100 percent oxygen begins to flow into the chamber. The chamber is pressurized gradually over 10 to 15 minutes. The patient breathes the pure oxygen for approximately 90 minutes, depending on the condition being treated. The hyperbaric chamber is equipped with an intercom system that allows the patient to communicate with physicians and staff while in the chamber. The patient can also watch television, listen to the radio or simply relax and sleep during treatment. After the prescribed treatment time, the flow of oxygen is stopped and the chamber is decompressed.