Solutions for Industry

ET has been designing, installing and supporting high quality Continuous Emissions Monitoring systems since 1983.

Our philosophy for CEMS remains unchanged to this day:- to supply CEMS that are of high quality, offer high reliability, are internationally approved and most importantly deliver maximum customer value and benefits, including the minimum of operator maintenance and lowest cost of long-term ownership.

At the heart of our CEM system is Opsis DOAS cross-duct technology. DOAS (Differential Optical Absorption Spectroscopy) is an optical, cross-duct, multi-gas measurement technology that measures stack gases directly without any contact as they pass through the stack. It is a true non-contact, nonextractive measurement based on the differential optical absorption of gas molecules in the UV, visible and IR wavelengths.

You can view Opsis videos on a whole range of applications on the Opsis Play page of their website.

By virtue of the fact that Opsis DOAS measures over a wide range of wavelengths, a corresponding wide range of organic and inorganic gases can be measured including NO, NO2 (direct), SO2, CO, CO2, HF, HCl, NH3, H2O, H2S, VOC’s, TOC and specific Aldehydes, Amines and VOC’s.

The system therefore can be easily tailored for almost any CEM and Process Control application and due to it’s non-contact, non-extractive principle of operation, requires the absolute minimum of operator involvement or maintenance.


Watch the video The Opsis System 400 explained - one system, three solutions.

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