Stationary source emissions. Determination of the mass concentration of carbon monoxide (CO). Reference method: non-dispersive infrared spectrometry Air pollution, Air, Quality, Stationary, Emission, Emission measurement, Chemical analysis & testing, Determination of content, Carbon monoxide, Pollutant gases, Combustion products, Concentration (chemical), Gas analysis, Flues, Chimneys, Incineration (waste), Sampling methods, Infrared spectrophotometry, Gas analyzers, Spectroscopy