{
  "url": "https://openlegislation.uk/air-quality-ozone-wales-regulations-2003/schedule-2/part-I",
  "json_url": "https://openlegislation.uk/air-quality-ozone-wales-regulations-2003/schedule-2/part-I.json",
  "legislation": "wsi/2003/1848",
  "legislation_title": "The Air Quality (Ozone) (Wales) Regulations 2003",
  "legislation_url": "https://openlegislation.uk/air-quality-ozone-wales-regulations-2003",
  "path": "schedule/2/part/I",
  "kind": "part",
  "number": "I",
  "heading": "Macroscale siting",
  "text": "Type of station\nObjective of measurement\nRepresentativeness\nMacroscale siting criteria\n(a)sampling points should also, where possible, be representative of similar locations not in their immediate vicinity.\nFor rural and rural background stations, consideration should be given, where appropriate, to co-ordination with the monitoring requirements of Commission Regulation (EC) No. 1091/94 concerning protection of the Community’s forests against atmospheric pollution.\nUrban\nProtection of human health: to assess the exposure of the urban population to ozone, i.e. where the population density and ozone concentration are relatively high and representative of the exposure of the general population.\nA few km2.\nAway from the influence of local emission such as traffic, petrol stations etc.;\nvented locations where well-mixed levels can be measured;\nlocations such as residential and commercial areas of cities, parks (away from the trees), big streets or squares with very little or no traffic, open areas characteristic of education, sports or recreation facilities.\nSuburban\nProtection of human health and vegetation: To assess the exposure of the population and vegetation located in the outskirts of the agglomeration, where the highest ozone levels, to which the population and vegetation is likely to be directly or indirectly exposed, occur.\nSome tens of km2\nAt a certain distance from the area of maximum emissions downwind following the main wind directions during conditions favourable to ozone formation;\nwhere population, sensitive crops or natural ecosystems located in the outer fringe of an agglomeration are exposed to high ozone levels;\nwhere appropriate, some suburban stations also upwind of the area of maximum emissions, in order to determine the regional background levels of ozone.\nRural\nProtection of human health and vegetation: To assess the exposure of population, crops and natural ecosystems to sub-regional scale ozone concentrations.\nSub-regional levels (a few km2)\nStations can be located in small settlement and/or areas with natural ecosystems, forests or crops;\nrepresentative for ozone away from the influence of immediate local emissions such as industrial installations and roads;\nat open area sites, but not on higher mountain-tops.\nRural background\nProtection of vegetation and human health: To assess the exposure of crops and natural ecosystems to regional-scale ozone concentrations as well as exposure of the populations.\nRegional/national/ continental levels (1,000 to 10,000km2)\nStation located in areas with lower population density, e.g. with natural ecosystems, forests, far removed from urban and industrial areas and away from local emissions;\navoid locations which are subject to locally enhanced formation of near-ground inversion conditions, also summits of higher mountains;\ncoastal sites with pronounced diurnal wind cycles of local character are not recommended.",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "footnote",
      "label": "f1",
      "text": "(a)sampling points should also, where possible, be representative of similar locations not in their immediate vicinity."
    },
    {
      "type": "footnote",
      "label": "f2",
      "text": "OJ L 125, 18.5.1994, p1."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/wsi/2003/1848/schedule/2/part/I",
    "retrieved_at": "2026-10-29T00:10:44.777755+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."
}