Do hospitals pump oxygen into the air?

No, hospitals do not pump oxygen into the air. Hospitals use HVAC systems to maintain a comfortable temperature and humidity level, as well as to filter out airborne contaminants. The air is circulated through a series of filters to remove dust, pollen, and other particles. The air is then heated or cooled as needed, and humidified or dehumidified to maintain a comfortable environment. Oxygen is not added to the air, as it is already present in the atmosphere.