{
  "url": "https://openlegislation.uk/clean-air-act-1956-repealed-2781993/section-21",
  "json_url": "https://openlegislation.uk/clean-air-act-1956-repealed-2781993/section-21.json",
  "legislation": "ukpga/Eliz2/4-5/52",
  "legislation_title": "Clean Air Act 1956 (repealed 27.8.1993)",
  "legislation_url": "https://openlegislation.uk/clean-air-act-1956-repealed-2781993",
  "path": "section/21",
  "kind": "section",
  "number": "21",
  "heading": "Exemption for purposes of investigations and research.",
  "text": "(1) If the local authority are satisfied, on the application of any person interested, that it is expedient so to do for the purpose of enabling investigations or research relevant to the problem of the pollution of the air to be carried out without rendering the applicant liable to proceedings brought under or by virtue of any of the under-mentioned provisions of this Act , the Clean Air Act 1968 or the Environmental Protection Act 1990 the local authority may by notice in writing given to the applicant exempt, wholly or to a limited extent,—\n(a) any chimney from the operation of sections 1, 11, 16 and 19 of this Act and section 2 of the Clean Air 1968 and Part III of the Environmental Protection Act 1990;\n(b) any furnace, boiler or industrial plant from the operation of section 3(1) of this Act;\n(c) any premises from the operation of section 1 of the said Act of 1968;\n(d) any furnace from the operation of sections 6 and 7 of this Act and section 3 of that Act;\n(e) the acquisition or sale of any fuel specified in the notice from the operation of section 9 of that Act,\nin each case subject to such conditions, if any, and for such period as may be specified in the notice.\n(2) Any person who has applied to the local authority for an exemption under this section may, if he is dissatisfied with the decision of the authority on the application, appeal to the Minister and the Minister may, if he thinks fit, by notice in writing given to the applicant and the local authority, give any exemption which the authority might have given or vary the terms of any exemption which they have given.",
  "extent": "E+W+S",
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "F",
      "label": "F1",
      "text": "Words substituted by Clean Air Act 1968 (c. 62), s. 14(1), Sch. 1 para. 6"
    },
    {
      "type": "F",
      "label": "F2",
      "text": "Words substituted by Environmental Protection Act 1990 (c. 43, SIF 46:4), s. 162(1), Sch. 15 para. 7(3)(a)"
    },
    {
      "type": "F",
      "label": "F3",
      "text": "S. 21(1)(a)–(e) substituted for s. 21(1)(a)–(c) by Clean Air Act 1968 (c. 62), Sch. 1 para. 6"
    },
    {
      "type": "F",
      "label": "F4",
      "text": "Words inserted by Environmental Protection Act 1990 (c. 43, SIF 46:4), s. 162(1), Sch. 15 para. 7(3)(b)"
    },
    {
      "type": "M",
      "label": "M1",
      "text": "1968 c. 62."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/ukpga/Eliz2/4-5/52/section/21",
    "retrieved_at": "2026-10-29T11:14:34.346401+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."
}