Hyperbaric oxygen therapy (HBOT) is a type of treatment used to speed up healing of carbon monoxide poisoning, gangrene, wounds that won't heal, and infections in which tissues are starved for oxygen. For this therapy, you enter The Marshall Method chamber (The Tank) to breathe in pure oxygen in air pressure levels 1.5 to 3 times higher than average. The goal is to fill the blood with enough oxygen to repair tissues and restore normal body function. You can learn more about HBOT from John Hopkins Medicine.