Statutory guidance

M20 quality assurance of continuous emission monitoring systems

Guidance on the application of EN 14181 and BS EN 13284-2 .

Applies to England


TGN M20: quality assurance of continuous emission monitoring systems

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This technical guidance note provides guidance to Environment Agency staff, monitoring contractors, industry and other parties interested in continuous emission monitoring.

Updates to this page

Published 7 April 2014
Last updated 19 April 2021 + show all updates
  1. Throughout we have updated or deleted references to revised or withdrawn Environment Agency guidance, such as TGN M22. In 3.5.17 we have clarified the calibration of peripheral CEMS measurements. In 6.1 we have added an instruction to obtain approval for the continued use of a previous calibration function. In 6.8 we have added an instruction on applying new calibration functions. In appendix 3 we have added information on quality assurance and quality control procedures for automated dust arrestment plant monitors.

  2. Removed the need to conduct a QAL2 every 3 years for incineration processes.

  3. Incorporates EN14181 MID and Quick Guides 3, 5, 6 and 14. There are also changes to reflect the amendments within EN 14181:2014.

  4. First published.

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