Cross-stack UV & FTIR DOAS Systems

OPSIS Cross-stack SystemOPSIS CEM systems measure multiple emissions or process gases in real time in situ. 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, H2S, NH3, CO, CO2, HF, H2O, CH4, Hg, HCl, Cl2, ClO2, CS2, Phenol, Formaldehyde, 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 TÜV and MCERTS according to EN 15267, and a range of other international authorities.

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  • Kemira Chemicals

    Demands from the authorities led the Swedish chemical producer Kemira Chemicals to install their first OPSIS system in 1988. Over the years, they have installed another five monitoring paths for measurement of SO2 and NOx.

    “The system just continues to run…”

    Read the full case here »