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TELEDYNE ELECTRONIC TECHNOLOGIES
Analytical Instruments
SECTION NINE EFFECT OF
HUMIDITY
Humidity does not directly affect the accuracy of the sensor's measurement. However, when a
nebuliser or other device is used to increase moisture levels in gas mixtures, the moisture actually
dilutes the mixture. This dilution effect decreases the oxygen concentr ation.
For example, if an 80% oxygen gas mixture is humidified to satur ation at room temperature, the
resulting gas mixture will contain only 77.5% oxygen. Your TED 191 Portable Oxygen Monitor
accurately measures decreases in the oxygen concentration due to the dilution effects of moisture
added to gas mixtures.
As with all oxygen sensors, excessive condensation on the sensing surface will block the diffusion
of oxygen to the sensor, rendering it inoperative. It is recomm ended that the sensor be installed on
the dry side of the breathing circuit at all times.
Water condensate on the exposed cable contacts at the rear of the sensor m ay affect the oxygen
reading and should be removed by shaking out the condensed water and allowing the sens or to
air dry.