{
  "url": "https://openlegislation.uk/air-quality-standards-wales-regulations-2007/regulation-2",
  "json_url": "https://openlegislation.uk/air-quality-standards-wales-regulations-2007/regulation-2.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/2",
  "kind": "regulation",
  "number": "2",
  "heading": "Definitions",
  "text": "(1) In these Regulations—\n“action plan” (“cynllun gweithredu”) means an action plan required by regulation 11;\n“agglomeration” (“crynhoad”) has the meaning given in regulation 5(2);\n“air quality standards” (“safonau ansawdd aer”) means limit values, target values and long-term objectives;\n“alert threshold” (trothwy rhybuddio”) means an alert threshold set out in Schedule 3;\n“ambient air” (“aer amgylchynol”) means outdoor air in the troposphere, excluding work places;\n“assessment” (“asesu”) means any method used to measure, calculate, predict or estimate the concentration of a pollutant;\n“attainment date” (dyddiad cyrhaeddiad”) means a date by which—\n(a) a limit value is required to be attained; or\n(b) a target value should be attained, insofar as this is possible;\n“concentration” (“crynodiad”) means—\n(a) for pollutants other than Group B pollutants, the concentration of the relevant pollutant in ambient air; or\n(b) for Group B pollutants, the total content of the relevant pollutant in the PM10 fraction in ambient air,\nand, in both cases, a reference to a concentration is to a concentration assessed by the National Assembly in accordance with these Regulations;\n“Group A pollutants” (“llygryddion Grŵp A”) means benzene, carbon monoxide, lead, nitrogen dioxide and oxides of nitrogen, PM10 and sulphur dioxide;\n“Group B pollutants” (“llygryddion Grŵp B”) means arsenic, benzo(a)pyrene, cadmium and nickel and their compounds;\n“improvement plan” (“cynllun gwella”) means an improvement plan required by regulation 8;\n“information threshold” (“trothwy gwybodaeth”) means the information threshold set out in Part 2 of Schedule 3;\n“limit value” (“gwerth terfyn”) means a maximum permitted concentration of a Group A pollutant set out in Part 1 of Schedule 1;\n“long-term objective” (“amcan hirdymor”) means a maximum concentration of ozone set out in Part 4 of Schedule 1;\n“margin of tolerance” (“ffin goddefaint”) means an amount specified in Part 2 of Schedule 1 by which a limit value may be exceeded;\n“oxides of nitrogen” (ocsidau nitrogen”) means the sum of nitric oxide and nitrogen dioxide added as parts per billion and expressed as nitrogen dioxide in microgrammes per cubic metre;\n“ozone precursor substances” (rhagsylweddau osôn”) means substances which contribute to the formation of ground level ozone, as referred to by regulation 18(1);\n“PM2·5” means particulate matter which passes through a size-selective inlet with a 50% efficiency cut-off at 2.5μm aerodynamic diameter;\n“PM10” means particulate matter which passes through a size-selective inlet with a 50% efficiency cut-off at 10μm aerodynamic diameter, in relation to which, in the case of assessments of Group B pollutants, the inlet is defined in EN 12341;\n“pollutant” (“llygrydd”) means—\n(a) any Group A pollutant;\n(b) any Group B pollutant;\n(c) ozone; or\n(d) any pollutant to which Part 3 of these Regulations applies;\n“polycyclic aromatic hydrocarbons” (“hydrocarbonau aromatig polysyclig”) means—\n(a) those compounds listed at regulation 19(2); and\n(b) any other polycyclic aromatic hydrocarbons the National Assembly chooses to monitor under regulation 19(1)(b);\n“rural background station” (“gorsaf cefndir gwledig”) is to be interpreted in accordance with Part 3 of Schedule 5;\n“target value” (“gwerth targed”) means a maximum concentration of a Group B pollutant as set out in Part 3 of Schedule 1 or ozone as set out in Part 4 of that Schedule; and\n“zone” (“parth”) means one of the parts of the territory into which the National Assembly has divided Wales under regulation 5(1) for the purposes of Part 2 of these Regulations; and references to a zone, unless the context indicates otherwise, include an agglomeration.\n(2) Other words and expressions used in these Regulations have the same meaning as in the following Directives—\n(a) Council Directive 96/62/EC on ambient air quality assessment and management;\n(b) Council Directive 1999/30/EC relating to limit values for sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter and lead in ambient air;\n(c) Directive 2000/69/EC of the European Parliament and of the Council relating to limit values for benzene and carbon monoxide in ambient air;\n(d) Directive 2002/3/EC of the European Parliament and of the Council relating to ozone in ambient air; and\n(e) Directive 2004/107/EC of the European Parliament and of the Council relating to arsenic, cadmium, mercury, nickel and polycyclic aromatic hydrocarbons in ambient air.",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "footnote",
      "label": "f1",
      "text": "OJ No L 296, 21.11.96, p.55."
    },
    {
      "type": "footnote",
      "label": "f2",
      "text": "OJ No L 163, 29.06.99, p.41."
    },
    {
      "type": "footnote",
      "label": "f3",
      "text": "OJ No L 313, 13.12.00, p.12."
    },
    {
      "type": "footnote",
      "label": "f4",
      "text": "OJ No L 67, 09.03.02, p.14."
    },
    {
      "type": "footnote",
      "label": "f5",
      "text": "OJ No L 23, 26.01.05, p.3."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/wsi/2007/717/regulation/2",
    "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."
}