{
  "url": "https://openlegislation.uk/control-of-substances-hazardous-to-health-regulations-1994/schedule-1",
  "json_url": "https://openlegislation.uk/control-of-substances-hazardous-to-health-regulations-1994/schedule-1.json",
  "legislation": "uksi/1994/3246",
  "legislation_title": "The Control of Substances Hazardous to Health Regulations 1994",
  "legislation_url": "https://openlegislation.uk/control-of-substances-hazardous-to-health-regulations-1994",
  "path": "schedule/1",
  "kind": "schedule",
  "number": "1",
  "heading": "LIST OF SUBSTANCES ASSIGNED MAXIMUM EXPOSURE LIMITS",
  "text": "The maximum exposure limits of the dusts included in the list below refer to the total inhalable dust fraction, unless otherwise stated.\nReference periods\nLong-term maximum exposure limit (8-hour TWA reference period)\nShort-term maximum exposure limit (15-minute reference period)\nSubstance\nFormula\nppm\nmg m−3\nppm\nmg m−3\n° In addition to the maximum exposure limit specified above man-made mineral fibre is also subject to a maximum exposure limit of 2 fibres ml−1, 8-hour TWA, when measured or calculated by a method approved by the Health and Safety Commission.\n* Limit relates to cyclohexane soluble material.\n# In addition to the maximum exposure limit specified above vinyl chloride is also subject to an overriding annual exposure limit of 3 ppm.\nAcrylamide\nCH2=CHCONH2\n—\n0.3\n—\n—\nAcrylonitrile\nCH2=CHCN\n2\n4\n—\n—\nArsenic & compounds except arsine (as As)\nAs\n—\n0.1\n—\n—\nBenzene\nC6H6\n5\n16\n—\n—\nBeryllium and beryllium compounds (as Be)\nBe\n—\n0.002\nBis (chloromethyl) ether\nC1CH2OCH2C1\n0.001\n0.005\n—\n—\nButa-1, 3-diene\nCH2=CHCH=CH2\n10\n22\n—\n—\n2-Butoxyethanol\nC4H9OCH2CH2OH\n25\n120\n—\n—\nCadmium & cadmium compounds, except cadmium oxide fume, cadmium sulphide and cadmium sulphide pigments (as Cd)\nCd\n—\n0.025\n—\n—\nCadmium oxide fume (as Cd)\nCdO\n—\n0.025\n—\n0.05\nCadmium sulphide and cadmium sulphide pigments (respirable dust as Cd)\nCdS\n—\n0.04\n—\n—\nCarbon disulphide\nCS2\n10\n30\n—\n—\nChromium (VI) compounds (as Cr)\nCr\n—\n0.05\n—\n—\nCobalt and cobalt compounds (as Co)\nCo\n—\n0.1\n—\n—\n1,2-Dibromoethane (Ethylene dibromide)\nBrCH2CH2Br\n0.5\n4\n—\n—\n1,2-Dichloroethane (Ethylene dichloride)\nC1CH2CH2C1\n5\n20\n—\n—\nDichloromethane\nCH2C12\n100\n350\n300\n1050\n2,2'-Dichloro-4,4'-methylene dianiline (mboca)\nCH2(C6H3C1NH2)2\n—\n0.005\n—\n—\n1-Chloro-2,3-epoxypropane (Epichlorohydrin)\n0.5\n2\n1.5\n6\n2-Ethoxyethanol\nC2H5OCH2CH2OH\n10\n37\n—\n—\n2-Ethoxyethyl acetate\nC2H5OCH2CH2OOCCH3\n10\n54\n—\n—\nEthylene oxide\n5\n10\n—\n—\nFormaldehyde\nHCHO\n2\n2.5\n2\n2.5\nGrain dust\n—\n10\n—\n—\nHydrogen cyanide\nHCN\n—\n—\n10\n10\nIsocyanates, all (as-NCO)\n—\n0.02\n—\n0.07\nMan-made mineral fibre\n—\n5\n—\n—\n2-Methoxyethanol\nCH3OCH2CH2OH\n5\n16\n—\n—\n2-Methoxyethyl acetate\nCH3COOCH2CH2OCH3\n5\n24\n—\n—\n4, 4'-Methylenedianiline\nCH2(C6H4NH2)2\n0.01\n0.08\n—\n—\nNickel and its inorganic compounds (except nickel carbonyl):\nNi\nwater-soluble nickel compounds (as Ni)\n—\n0.1\n—\n—\nnickel and water-insoluble nickel compounds (as Ni)\n—\n0.5\n—\n—\n2-Nitropropane\nCH3CH(NO2)CH3\n5\n18\n—\n—\nRubber process dust\n—\n6\n—\n—\nRubber fume\n—\n0.6\n—\n—\nSilica, respirable crystalline\nSiO2\n—\n0.4\n—\n—\nStyrene\nC6H5CH=CH2\n100\n420\n250\n1050\n1, 1, 1-Trichloroethane\nCH3CC13\n350\n1900\n450\n2450\nTrichloroethylene\nCC12=CHC1\n100\n535\n150\n802\nVinyl chloridea\nCH2=CHC1\n7\n—\n—\n—\nVinylidene chloride\nCH2=CC12\n10\n40\n—\n—\nWood dust (hard wood)\n—\n5\n—\n—",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "footnote",
      "label": "f1",
      "text": "° In addition to the maximum exposure limit specified above man-made mineral fibre is also subject to a maximum exposure limit of 2 fibres ml−1, 8-hour TWA, when measured or calculated by a method approved by the Health and Safety Commission."
    },
    {
      "type": "footnote",
      "label": "f2",
      "text": "* Limit relates to cyclohexane soluble material."
    },
    {
      "type": "footnote",
      "label": "f3",
      "text": "# In addition to the maximum exposure limit specified above vinyl chloride is also subject to an overriding annual exposure limit of 3 ppm."
    }
  ],
  "outstanding_effects": [
    {
      "type": "substituted",
      "affecting": "uksi/1996/3138",
      "affecting_title": "The Control of Substances Hazardous to Health (Amendment) Regulations 1996"
    },
    {
      "type": "amended",
      "affecting": "uksi/1998/1357",
      "affecting_title": "The Control of Substances Hazardous to Health (Amendment) Regulations 1998"
    }
  ],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/uksi/1994/3246/schedule/1",
    "retrieved_at": "2026-10-29T13:20:00.945543+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."
}