NOX Stack Gas Monitor

Chemiluminescence has long been recognized as the best practical analytical method for NOx detection at parts per billion level and with little or no interference from other pollutant gases. A sample containing nitric oxide is mixed with a large quantity of ozone. The nitric oxide reacts with the ozone to produce nitrogen dioxide in excited state. These excited molecules relaxes to ground state by emitting light in the region 600-2800nm which is measured using a photomultiplier Tube. The amount of light produced is proportional to the amount of nitric oxide in the sample.