Paramagnetic oxygen analysis

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Paramagnetic oxygen analysis is a way of obtaining fast, accurate oxygen measurements by using magnetic fields. Oxygen, unlike most gases, is attracted to strong magnetic fields.

The analyzer typically consists of a focused magnetic field, two nitrogen-filled glass spheres in a dumbbell configuration, and a precision optical system consisting of a light source, photodiode and amplifier circuit. As gas moves through the magnetic field, it is attracted to the strongest part, causing the dumbbell to rotate. The current required to keep the dumbbell in its original state is directly proportional to the partial pressure of oxygen and is represented electronically in percent oxygen.^[1]