A medical device is attached to a medical piping system and operates upon medical gases to perform a specific function. Medical gases include medical air, medical vacuum, oxygen, carbon dioxide, nitrogen, and nitrous oxide. Outlets for medical gasses are not classified as medical devices, they are classified as Valves. Cylinders/Tanks for medical gasses are not classified as medical devices, they are classified at Tanks. See IFC4 definition of _IfcMedicalDevice_ for more information.
Breathing air plant is a medical device that provides air purified to a level safe to breath, composed of an air compressor and air treatment line.