The EXM400 is an extractive online gas analysers dedicated to continuous emission monitoring (CEM). It covers applications like DeNOx systems on power plants, generators, chemical plants, petro-chemical plants, or biogas reactors.

The EXM400 is based on UV spectroscopy that brings a higher sensitivity and stability  than infra-red systems and also gives the possibility to measure several gases simultaneously, example: NH3, SO2, NO.

A high selectivity is achieved by a fast Fourier transform (FFT) on the absorbance spectrum for all the gases having a periodic structure like NH3, SO2, CS2 and others.

All the internal gas circuit is heated at 190°C to admit directly hot and humid combustion gas.

There is no risk of interference with H2O, CO, CO2 or CH4 as all theses gases have no absorbance on the UV range.