Monitoring emissions to air, land and water (MCERTS)

If your business produces potentially harmful emissions and you’re an environmental permit holder you must use the Monitoring Certification Scheme (MCERTS).

You may need an environmental permit if your business activities produce emissions that could pollute the air, water or land. The permit sets out how to monitor your emissions.

Check if you need an environmental permit.

MCERTS is the Environment Agency’s Monitoring Certification Scheme for environmental permit holders. The documents on this page provide a framework for your business to meet the Environment Agency’s quality requirements for emissions monitoring.

MCERTS is used to approve people, instruments and laboratories.

Contact the Environment Agency if you need any help.

Environment Agency

PO Box 544

S60 1BY


Monday to Friday, 8am to 6pm 0370 8506 506

From outside the UK +44 1709 389 201

Find an MCERTS accredited laboratory.

Find a list of MCERTS certified instruments and products.

Download the Method Implementation Documents (MIDs) for stack emission monitoring.

Operator monitoring assessment (OMA)

Your environmental permit sets out requirements for self-monitoring of emissions to air or discharges water. The Environment Agency checks these requirements using OMA.

Find out how to prepare for your assessment for either emissions to air or discharges to water.

Water and flow monitoring performance standards and test procedures

MCERTS for flow monitoring, water monitoring equipment and accreditation of laboratories that analyse water samples.

Stack emissions monitoring performance standards and test procedures

Ambient air monitoring performance standards

MCERTS certification of equipment that monitors pollution in the ambient air.

Soil monitoring performance standards

Find out how to submit chemical test data on potentially contaminated soils to the Environment Agency.

Data must meet quality requirements set out in the MCERTS standard.

You can submit results from on-site testing using rapid measurement techniques. You must back up these results with suitable MCERTS accredited laboratory analyses.

You must also provide evidence of appropriate quality control and calibration procedures.

Environmental data management software

How to develop, validate and maintain software used for processing data from emissions monitoring.

Monitoring guides

Technical guidance notes and regulatory monitoring quick guides.

Published 7 April 2014
Last updated 14 June 2024 + show all updates
  1. Added 'MCERTS: performance standard for long-term samplers of carbon dioxide' to 'Stack emissions monitoring performance standards and test procedures'.

  2. Added 'Monitoring stack emissions: standards for continuous monitoring and sampling' to the 'Monitoring guides' section.

  3. Added a link to 'MCERTS: performance standards and test procedures for event duration monitors'.

  4. Added the document 'MCERTS: requirements for installing and using event duration monitors'.

  5. Added links to 'MCERTS performance standards for ambient monitoring equipment' and 'MCERTS: performance standards for low risk plant monitors'.

  6. Added a link to new guidance - 'MCERTS: performance standards and test procedures for event duration monitors'.

  7. Added the updated guidance 'Monitoring stack emissions: measurement locations' and removed the document this is replacing, 'M1 sampling requirements for stack emission monitoring'.

  8. Added the updated version of Minimum requirements for self-monitoring of flow: MCERTS performance standard.

  9. Added the latest version of 'MCERTS personnel competency standard manual stack emissions monitoring'.

  10. Added 'MCERTS for stack emissions monitoring equipment at industrial installations' to the collection. This replaces the older guidance 'MCERTS: performance standards for continuous emission monitoring systems (CEMs) and transportable CEMs' and 'MCERTS: performance standards and test procedures for automated dust arrestment plant monitors' - these have been withdrawn.

  11. Added 4 new guidance documents that were previously part of M18. Monitoring discharges to water: guidance on selecting a monitoring approach, Monitoring discharges to water: CEN and ISO monitoring methods, Monitoring discharges to water: alternative monitoring methods, Monitoring discharges to water: analytical quality control charts.

  12. Amended to include the updated guidance on monitoring stack emissions to air (formerly M2).

  13. New document 'M5 Monitoring of stack gas emissions from medium combustion plants and specified generators' added under the list of monitoring guides.

  14. Added link to: 'MCERTS: performance standard for laboratories testing samples from stack emissions monitoring' and 'M9: environmental monitoring of bioaerosols at regulated facilities'.

  15. Text added to clarify quality requirements for chemical test data on potentially contaminated soils.

  16. Added link to MCERTS: manual stack emissions monitoring, guide 11.

  17. First published.