There are 2 main types of hyperbaric oxygen therapy, HBOT and mHBOT or "mild" hyperbaric oxygen therapy; more accurately, high pressure and low pressure hyperbaric.
High pressure is generally referred to as high pressure HBOT, hospital grade HBOT, or just HBOT and is designated as above 2 absolute atmospheres. Low pressure hyperbaric oxygen therapy referred to as mild hyperbarics or mHBOT. This is hyperbaric oxygen administered at 1.3 absolute atmospheres. Each type of hyperbaric oxygen therapy has specific indications, advantages and disadvantages. The higher pressures are useful in acute trauma like crush injuries and severe burns. Lower pressures are more effective for chronic systemic illnesses and neurological conditions. Current research and clinical observation is showing that, for many difficult-to-treat medical conditions, mild hyperbaric is proving to be a better tolerated and more effective treatment approach.
Pioneer Valley Hyperbaric offers exclusively mild HBOT, delivered at 1.3 atmospheres.  This type of HBOT is effective for a large number of chronic medical illnesses, and is safe enough to administer in the outpatient office, or even at home without the immediate supervision of a medical professional.