{
  "url": "https://openlegislation.uk/air-quality-standards-wales-regulations-2007/regulation-20",
  "json_url": "https://openlegislation.uk/air-quality-standards-wales-regulations-2007/regulation-20.json",
  "legislation": "wsi/2007/717",
  "legislation_title": "The Air Quality Standards (Wales) Regulations 2007",
  "legislation_url": "https://openlegislation.uk/air-quality-standards-wales-regulations-2007",
  "path": "regulation/20",
  "kind": "regulation",
  "number": "20",
  "heading": "Background monitoring",
  "text": "(1) The National Assembly must, in accordance with paragraphs (3) and (4), install and operate background sampling points to provide the measurements required by paragraph (2).\n(2) The measurements required by this regulation are indicative measurements of—\n(a) concentrations of—\n(i) Group B pollutants,\n(ii) polycyclic aromatic hydrocarbons, and\n(iii) total gaseous mercury as defined in paragraph (6);\nand\n(b) total deposition of—\n(i) Group B pollutants within the PM10 fraction,\n(ii) polycyclic aromatic hydrocarbons, and\n(iii) mercury.\n(3) For the purposes of paragraphs (1) and (2), the National Assembly must ensure that—\n(a) at least one sampling point is installed for every 100,000 km2; and\n(b) each sampling point is located in accordance with Parts 2, 4 and 5 of Schedule 5.\n(4) Regulation 16(2) and (3) applies to the measurements required by this regulation.\n(5) The National Assembly may—\n(a) in addition to the indicative measurements required by paragraph (2), take further indicative measurements relating specifically to particulate and gaseous divalent mercury from the sampling points required to be installed by paragraph (1); and\n(b) coordinate any measurements taken under this regulation with the European Monitoring and Evaluation of Pollutants monitoring strategy and measurement programme.\n(6) For the purpose of paragraph (2)(a)(iii), “total gaseous mercury” (“mercwri nwyol llwyr”) means—\n(a) elemental mercury vapour (Hg0); and\n(b) reactive gaseous mercury.",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/wsi/2007/717/regulation/20",
    "retrieved_at": "2026-10-29T00:01:33.213395+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."
}