Carbon monoxide analyzer

Regulatory Measurement of Carbon Monoxide


The NDIR GFC (Non Dispersive InfraRed Gas Filter Correlation) carbon monoxide analyzer CO12M, combines over 25 years of experience in the NDIR CO measurement with an enhanced electronics package and a modular component parts design.

Supplier: Environment SA


  • Temperature-controlled optical bench
  • Automatic pressure compensation
  • User programmable ranges and average times
  • Full remote emulation of the analyzer

The CO sample concentration is determined by measuring the quantity of infrared light the sample gas absorbs as it flows through a multi-cell correlation wheel filled on one side with a reference CO cell (reference beam) and on the other side with an empty cell (the measurement beam). As the wheel turns round, the light beam passes alternatively through the CO cell and the empty cell and then through an interference optical filter before reaching the optical detector. If the sample contains CO, the reference beam will not be attenuated by it because it was already attenuated by the CO of the reference cell.


  • Lower detectable limit (2s): 40 ppb
  • Response time: automatic and programmable (minimum 30 sec)
  • Zero drift: less than 0.5 ppm / 24 h and less than 0.1 ppm / 7 days

Product applications

  • Ambient air monitoring
  • Mobile laboratory
  • Continuous emissions monitoring (CEM) by dilution extraction