{
  "url": "https://openlegislation.uk/eu-decision-2004-470/annex/division-3/division-1",
  "json_url": "https://openlegislation.uk/eu-decision-2004-470/annex/division-3/division-1.json",
  "legislation": "eudn/2004/470",
  "legislation_title": "Commission Decision of 29 April 2004 concerning guidance on a provisional reference method for the sampling and measurement of PM2.5 (notified under document number C(2004) 1713) (Text with EEA relevance) (2004/470/EC)",
  "legislation_url": "https://openlegislation.uk/eu-decision-2004-470",
  "path": "annex/division/3/division/1",
  "kind": "division",
  "number": null,
  "heading": "Regarding the measurement method:",
  "text": "The mandate given by the Commission to CEN specified that the measurement method to be standardised is based on the gravimetric determination of the PM2.5 mass fraction of particulate matter collected on a filter under ambient conditions. Other methods, such as the beta ray attenuation method and the tapered element oscillating microbalance (TEOM), are currently tested for equivalence with the gravimetric method by CEN WG15.",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eudn/2004/470/annex/division/3/division/1",
    "retrieved_at": "2026-11-01T15:18:12.040498+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}