{
  "url": "https://openlegislation.uk/air-quality-standards-wales-regulations-2010/schedule-4/paragraph-wrapper4n1",
  "json_url": "https://openlegislation.uk/air-quality-standards-wales-regulations-2010/schedule-4/paragraph-wrapper4n1.json",
  "legislation": "wsi/2010/1433",
  "legislation_title": "The Air Quality Standards (Wales) Regulations 2010",
  "legislation_url": "https://openlegislation.uk/air-quality-standards-wales-regulations-2010",
  "path": "schedule/4/paragraph/wrapper4n1",
  "kind": "paragraph",
  "number": null,
  "heading": null,
  "text": "Alert thresholds for sulphur dioxide and nitrogen dioxide\nPollutant\nAlert threshold\nSulphur dioxide\n500 μg/m3\nNitrogen dioxide\n400 μg/m3\nInformation and alert thresholds for ozone\nPurpose\nAveraging period\nThreshold\nInformation\n1 hour\n180 μg/m3\nAlert\n1 hour\n240 μg/m3",
  "extent": "E+W",
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "M",
      "label": "M1",
      "text": "To be measured over three consecutive hours at locations representative of air quality over at least 100 km2 or an entire zone, whichever is smaller."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/wsi/2010/1433/schedule/4/paragraph/wrapper4n1",
    "retrieved_at": "2026-10-28T23:53:41.556554+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."
}