{
  "url": "https://openlegislation.uk/dark-smoke-permitted-periods-regulations-1958/regulation-3",
  "json_url": "https://openlegislation.uk/dark-smoke-permitted-periods-regulations-1958/regulation-3.json",
  "legislation": "uksi/1958/498",
  "legislation_title": "The Dark Smoke (Permitted Periods) Regulations 1958",
  "legislation_url": "https://openlegislation.uk/dark-smoke-permitted-periods-regulations-1958",
  "path": "regulation/3",
  "kind": "regulation",
  "number": "3",
  "heading": null,
  "text": "(1) Subject to the provisions of these regulations, emissions of dark smoke from any chimney for not longer than 10 minutes in the aggregate in any period of 8 hours, or, if soot-blowing is carried out within any such period, for not longer than 14 minutes in the aggregate in that period, shall be left out of account for the purposes of section 1 of the Act of 1956.\n(2) The said periods of 10 minutes and 14 minutes shall be increased in the case of a chimney serving 2 furnaces to 18 minutes and 25 minutes respectively, in the case of a chimney serving 3 furnaces to 24 minutes and 34 minutes respectively, and in the case of a chimney serving 4 or more furnaces to 29 minutes and 41 minutes respectively.",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/uksi/1958/498/regulation/3",
    "retrieved_at": "2026-10-30T01:03:34.826575+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."
}