OPSIS AQM systems measure multiple gases in real time over an open path. Using the DOAS (Differential Optical Absorption Spectroscopy) technique, the system is non-contact, with fast response.

One system can be configured to monitor NO, NO2, SO2, O3, BTX, NH3, CO, CO2, HF, H2O, CH4, Hg, HCl, among other gaseous compounds.

A basic system includes an analyser, an emitter/receiver set, and an optical fibre cable.

The system has been tested and approved by U.S. EPA, Chinese EPA, and TÜV according to EN 15267, and a range of other international authorities