{
  "url": "https://openlegislation.uk/control-of-major-accident-hazards-regulations-1999/schedule-1/part-5/paragraph-4",
  "json_url": "https://openlegislation.uk/control-of-major-accident-hazards-regulations-1999/schedule-1/part-5/paragraph-4.json",
  "legislation": "uksi/1999/743",
  "legislation_title": "The Control of Major Accident Hazards Regulations 1999",
  "legislation_url": "https://openlegislation.uk/control-of-major-accident-hazards-regulations-1999",
  "path": "schedule/1/part/5/paragraph/4",
  "kind": "paragraph",
  "number": "4",
  "heading": null,
  "text": "The addition of dangerous substances to determine the quantity present at an establishment shall be carried out according to the following rule:—\nif the sum\nq1Q+q2Q+q3Q+q4Q+q5Q+...>1 where\nqx the quantity of dangerous substances x (or category of dangerous substances) falling within Parts 2 or 3 of this Schedule,\nQ the relevant threshold quantity from Parts 2 or 3,\nthen the establishment is covered by the relevant requirements of these Regulations.\nThis rule will apply for the following circumstances—\n(a) for substances and preparations appearing in Part 2 at quantities less than their individual qualifying quantity present with substances having the same classification from Part 3, and the addition of substances and preparations with the same classification from Part 3;\n(b) for the addition of categories 1, 2 and 9 present at an establishment together;\n(c) for the addition of categories 3, 4, 5, 6, 7a, 7b and 8, present at an establishment together.",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [
    {
      "type": "words inserted",
      "affecting": "uksi/2014/162",
      "affecting_title": "The Heavy Fuel Oil (Amendment) Regulations 2014"
    },
    {
      "type": "substituted",
      "affecting": "uksi/2005/1088",
      "affecting_title": "The Control of Major Accident Hazards (Amendment) Regulations 2005"
    }
  ],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/uksi/1999/743/schedule/1/part/5/paragraph/4",
    "retrieved_at": "2026-10-29T10:55:56.898069+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."
}