The FLO2MAX oxygen mask has three highly sensitive one-way valve systems that deliver exactly the percentage of oxygen the patient requires by simply adjusting the flowmeter - from 30% to 99%. The sequence of the valve opening order starts when the patient makes an inspiratory effort of 1cm H2O/l/sec. causing the oxygen delivery valve to open; the patient inhales. The exhalation valve cracks at about 1.20cm.H2O/l/sec. and exhalation occurs normally.
At times a patient's peak inspiratory flowrate will exceed the flow rate of the supplied oxygen; if that happens the inspiratory valve to atmosphere will open at 1.30cm.H2O/l/sec., allowing supplementary air to match their inspiratory effort and minute volume. If the oxygen supply should cease flowing to the facemask, the patient would breathe normally through the inspiratory valve and exhale through the filter and exhalation valve.
When using a nebulizer with the FLO2MAX the oxygen delivery valve will open upon inspiration allowing the medication to travel to the patient. All excess medication and patient exhalation travels through the HEPA filter and out the exhalation valve, thereby protecting the care giver from unwanted exposure to medication and possible infection.