They are pressurized with air and the patient breathes oxygen through a built-in system. Multiplace chambers accommodate between four and twenty-four patients. They also are pressurized with air and the patients breathe oxygen through a similar built in system as the dualplace chamber. These chambers are large enough for stretchers, critical care patients, and medical staff. All chambers have the capability of communication with those outside through an intercom system.
Most chambers allow the patient to sleep, watch TV, or listen to music during the session.
There are two primary agencies that oversee the use of hyperbaric oxygen therapy. The American Board of Hyperbaric Medicine certifies physicians as hyperbaricists. These physicians are specially trained in the use of hyperbaric oxygen therapy. The Hyperbaric Oxygen Therapy Committee of the UHMS, developed in 1976, reviews published data regarding hyperbaric oxygen therapy and publishes periodic reports of recommended medical indications for hyperbaric oxygen therapy. The UHMS categorizes diseases by their need for treatment with hyperbaric oxygen therapy.