Change of https://www.gov.uk/government/publications/monitoring-discharges-to-water-cen-and-iso-monitoring-methods

Change description : 2026-09-17 13:18:00: Updated the entry for ‘Perfluoroalkyl and polyfluoroalkyl substances (PFAS)’ in line with BS ISO 21675. [Guidance and regulation]

Showing diff : 2026-09-08 14:41:01.177593990 +00:00..2026-09-17 12:18:29.674757786 +00:00

Guidance

Monitoring discharges to water: CEN and ISO monitoring methods

Formerly part of M18, index of CEN and ISO monitoring methods for monitoring discharges to water.

From:
Environment Agency
Published:
11 June 2020
Last updated:
817 September 2026 — See all updates

Applies to England

Documents

Monitoring discharges to water: CEN and ISO monitoring methods

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Details

The methods in this document are international standards recommended by regulation.

Updates to this page

Published 11 June 2020
Last updated 817 September 2026 — Show all updates

  1. Updated the entry for 'Perfluoroalkyl and polyfluoroalkyl substances (PFAS)' in line with BS ISO 21675.

  2. A standard for polyfluoroalkyl substances (PFAS) has been added in place of the standard for Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA)

  3. New standards added for biochemical oxygen demand (BOD), cyanide, nitrogen (total), total organic carbon, organochlorine pesticides, polycyclic aromatic hydrocarbons, short-chain polychlorinated alkanes, and volatile organic carbons. Those for BOD and nitrogen (total) supersede previous versions.

  4. First published.

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Update history

2026-09-17 13:18
Updated the entry for ‘Perfluoroalkyl and polyfluoroalkyl substances (PFAS)’ in line with BS ISO 21675.

2026-09-08 15:40
A standard for polyfluoroalkyl substances (PFAS) has been added in place of the standard for Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA)

2023-01-18 14:04
New standards added for biochemical oxygen demand (BOD), cyanide, nitrogen (total), total organic carbon, organochlorine pesticides, polycyclic aromatic hydrocarbons, short-chain polychlorinated alkanes, and volatile organic carbons. Those for BOD and nitrogen (total) supersede previous versions.