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These recommendations are not based on any regulatory requirements, but on gathered knowledge and  experiences collected from many Continuous Emissions Monitorning CEM operators. Each day perform this quick review of available information on the status of the CEM system so you can determine if anything needs immediate attention, attention sometime today or no attention at all.


  1. Each day, find the reports which are generated automatically overnight. Look these reports over and respond as needed. These reports typically include:

    1. A “Calibration Detail Report” showing the results from this morning’s daily calibration check. Any monitor which shows that it failed its calibration requires immediate attention. Any monitor which shows that the calibration results were at or above the maintenance limits, requires attention and possible adjustment sometime today, before your shift ends. Remember, if an adjustment is made, a follow up  hands off” successful calibration check is required by CEM regulations.
    2. An “Average Data Report” showing the measured hourly averages for the data from the monitors from yesterday.
    3. A second “Average Data Report” showing the derived (calculated) hourly values  from yesterday.
    4. A “Process Now History” report, which documents any error encountered when the various Process Now sequence ran earlier today.
    5. Other reports might be generated as well, showing extended averages (3-hour, 24-hour, 30-day, etc.) or year to date totals, or the results of other calculations.
    6. If your system has an opacity monitor, then the system should also generate an “Opacity Matrix Report”, which lists all the 6-minute average from the previous day.
    7. If your unit started up within the past 24 hours, verify the system performed a calibration check on all the monitors within the 8-hour startup grace period. This includes a weekly integrity check if you are operating a Hg CEMS.
  2. A few times per week, review the status of the CEM system with the control room operator and see if there are any CEM system alarms up and present.

  3. On Thursday or Friday, make a trip to the shelter and make sure everything looks good. Look over the air clean up system and make sure it’s in good shape. Double check the pressure in the calibration bottles and make sure there > 500 psi to get the calibration checks through Monday.

For questions, suggestions, or for a general chat, do not hesitate to contact me.

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Jon Konings

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