Open-Path UV & FTIR DOAS Systems

OPSIS Open-path SystemOPSIS 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.

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  • OPSIS Monitoring Services

  • Fence-line Monitoring

  • OPSIS Open-Path DOAS

  • Annual Calibration

  • Benzene Fence-line Monitoring at Refineries

  • OPSIS DOAS in Swansea, by Enviro Technology