NARSTO Measurement Methods Compendium CO Methods

1. CO

   1. Non-Dispersive Infrared Photometry (NDIR) - (FRM)
      1. Basis: Infrared light from a conventional source passes through two parallel cells. The reference cell contains a gas that will not absorb the radiation. The sample cell is continuously pumped with ambient air. The CO in the sample cell will absorb radiation at ~4.6 µm. The difference in the intensities of the light beams passing through the cells is used to determine the concentration of CO.
      2. Range: 0-100 ppmv
      3. Minimum Detection Level: 0.1-0.4 ppmv
      4. Operating Temperature: Relatively independent of normal ambient air temperature changes.
      5. Known Interference: Water vapor and CO₂
      6. Notes of Interest: There are two major varieties of NDIR analyzers: Luft-type detector and Gas-Filter Correlation (GFC) monitors. GFC monitors are smaller, eliminate interference from CO₂, and greatly reduce water vapor interference.
      7. Instrument - Manufacturer:
         1. Advanced Pollution Instrumentation, Inc. Model 300 CO Analyzer - Advanced Pollution Instrumentation, Inc.
         2. Beckman Model 866 CO Monitoring System - Beckman Coulter.
         3. Bendix/Combustion Engineering Model 8501-5CA CO Analyzer - Bendix Corporation (refer to ABB Process Analytics)
         4. Dasibi Model 3003 and 3008 CO Analyzers - Dasibi Environmental Corp.
         5. Environnement S.A. Model CO11M CO Analyzer - Environnement S.A. Inc. (refer to Thermo Environmental Instruments Inc.)
         6. MSA/LIRA Model 202S CO Analyzer System - Mine Safety Appliances Company
         7. Thermo Electron/Thermo Environmental Instruments Models 48 and 48C - Thermo Environmental Instruments Inc.
      8. References:

For definitions of method description terms see the Annotated Method Description Outline and Definitions.

For more information on FRM/FEM instrumentation, visit the AMTIC Designated Methods -- CO.