{
  "url": "https://openlegislation.uk/air-quality-limit-values-wales-regulations-2001/schedule-1/paragraph-1.1",
  "json_url": "https://openlegislation.uk/air-quality-limit-values-wales-regulations-2001/schedule-1/paragraph-1.1.json",
  "legislation": "wsi/2001/2683",
  "legislation_title": "The Air Quality Limit Values (Wales) Regulations 2001",
  "legislation_url": "https://openlegislation.uk/air-quality-limit-values-wales-regulations-2001",
  "path": "schedule/1/paragraph/1.1",
  "kind": "paragraph",
  "number": "1.1",
  "heading": "Limit values for sulphur dioxide",
  "text": "Averaging Period\nLimit value\nMargin of tolerance\nDate by which limit value is to be met\n1 Hourly limit value for the protection of human health\n1 hour\n350 μg/m3, not to be exceeded more than 24 times a calendar year\n150 μg/m3 (43%) on 19 July 1999, reducing on 1 January 2001 and every 12 months thereafter by equal annual percentages to reach 0% by 1 January 2005\n1 January 2005\n2 Daily limit value for the protection of human health\n24 hours\n125 μg/m3, not to be exceeded more than 3 times a calendar year\nNone\n1 January 2005\n3 Limit value for the protection of ecosystems\nCalendar year and winter (1 October to 31 March)\n20 μg/m3\nNone\n19 July 2001",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "footnote",
      "label": "f1",
      "text": "The figures for Margins of Tolerance for each of the relevant pollutants given in this Schedule are calculated from those given in Annex 1 of Directive 99/30/EC. This gave a figure above the limit value for each relevant pollutant, reducing by equal annual percentages from the date of entry into force of that Directive in 1999."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/wsi/2001/2683/schedule/1/paragraph/1.1",
    "retrieved_at": "2026-10-29T00:15:58.976500+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."
}