{
  "url": "https://openlegislation.uk/air-quality-regulations-1997/schedule",
  "json_url": "https://openlegislation.uk/air-quality-regulations-1997/schedule.json",
  "legislation": "uksi/1997/3043",
  "legislation_title": "The Air Quality Regulations 1997",
  "legislation_url": "https://openlegislation.uk/air-quality-regulations-1997",
  "path": "schedule",
  "kind": "schedule",
  "number": null,
  "heading": "AIR QUALITY OBJECTIVES",
  "text": "TABLE\nSubstance\nAir Quality Objective levels\nBenzene\n5 ppb or less, when expressed as a running annual mean\n1,3-Butadiene\n1 ppb or less, when expressed as a running annual mean\nCarbon Monoxide\n10 ppm or less, when expressed as a running 8 hour mean\nLead\n0.5 micrograms per cubic metre or less, when expressed as an annual mean\nNitrogen Dioxide\n150 ppb or less, when expressed as an hourly mean, and 21 ppb or less, when expressed as an annual mean\nPM10\n50 micrograms per cubic metre or less, when expressed as the 99th percentile of daily maximum running 24 hour means\nSulphur Dioxide\n100 ppb or less, when expressed as the 99.9th percentile of 15 minute means",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/uksi/1997/3043/schedule",
    "retrieved_at": "2026-10-29T11:40:04.923689+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."
}