{
  "url": "https://openlegislation.uk/eu-directive-2013-59/annex-II",
  "json_url": "https://openlegislation.uk/eu-directive-2013-59/annex-II.json",
  "legislation": "eudr/2013/59",
  "legislation_title": "Council Directive 2013/59/Euratom of 5 December 2013 laying down basic safety standards for protection against the dangers arising from exposure to ionising radiation, and repealing Directives 89/618/Euratom, 90/641/Euratom, 96/29/Euratom, 97/43/Euratom and 2003/122/Euratom",
  "legislation_url": "https://openlegislation.uk/eu-directive-2013-59",
  "path": "annex/II",
  "kind": "annex",
  "number": "II",
  "heading": "Radiation and tissue weighting factors as referred to in points (25) and (33) of Article 4",
  "text": "A.\nRadiation weighting factors\nNote: All values relate to the radiation incident on the body or, for internal radiation sources, emitted from the incorporated radionuclide(s).\nRadiation type\nwR\nPhotons\n1\nElectrons and muons\n1\nProtons and charged pions\n2\nAlpha particles, fission fragments, heavy ions\n20\nNeutrons, En < 1 MeV\n2,5 + 18,2 e - ln En 2 ∕ 6\nNeutrons, 1 MeV ≤ En ≤ 50 MeV\n5,0 + 17,0 e - ln 2 En 2 ∕ 6\nNeutrons, En > 50 MeV\n2,5 + 3,25 e - ln 0,04 En 2 ∕ 6\nB.\nTissue weighting factors\nThe wT for the remainder tissues (0,12) applies to the arithmetic mean dose of the 13 organs and tissues for each sex listed below. Remainder tissues: adrenals, extrathoracic (ET) region, gall bladder, heart, kidneys, lymphatic nodes, muscle, oral mucosa, pancreas, prostate (male), small intestine, spleen, thymus, uterus/cervix (female).\nTissue\nwT\nBone-marrow (red)\n0,12\nColon\n0,12\nLung\n0,12\nStomach\n0,12\nBreast\n0,12\nRemainder tissues\n0,12\nGonads\n0,08\nBladder\n0,04\nOesophagus\n0,04\nLiver\n0,04\nThyroid\n0,04\nBone surface\n0,01\nBrain\n0,01\nSalivary glands\n0,01\nSkin\n0,01",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "footnote",
      "label": "f1",
      "text": "The wT for the remainder tissues (0,12) applies to the arithmetic mean dose of the 13 organs and tissues for each sex listed below. Remainder tissues: adrenals, extrathoracic (ET) region, gall bladder, heart, kidneys, lymphatic nodes, muscle, oral mucosa, pancreas, prostate (male), small intestine, spleen, thymus, uterus/cervix (female)."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eudr/2013/59/annex/II",
    "retrieved_at": "2026-11-01T15:21:50.860989+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."
}