Statox 501 - IR Infrared Gas Detection - Brochure

Infrared gas detection -Theory of operation

Some gases absorb light at a certain wavelength (colour). This absorption band is specific to the gas. The rate of the absorption depends not only on the substance to be detected but also on the number of gas molecules (i. e. the concentration of the gas) This effect can be used to detect gases: The oscillation of the C - H bond in hydrocarbon molecules for instance absorbs light at 3,4 nm.