All ozone generators change only a small fraction of the oxygen into ozone. The factors that determine the ratio of oxygen to ozone ratio are the strength of the plasma/corona field, the flow rate of oxygen, the frequency of the plasma/corona field, ambient temperature and efficiency of the plasma/corona cell.That is why you see therapeutic machines being rated as ug (micrograms, or molecular weight of the ozone produced) per millilitre of oxygen/ozone mixture. This measurement is also called gamma.
Air and water ozonators on the other hand are usually measured in mg( again, molecular weight of the ozone produced) per hour.
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