{
  "url": "https://openlegislation.uk/ionising-radiations-regulations-2017/schedule-7/part-2",
  "json_url": "https://openlegislation.uk/ionising-radiations-regulations-2017/schedule-7/part-2.json",
  "legislation": "uksi/2017/1075",
  "legislation_title": "The Ionising Radiations Regulations 2017",
  "legislation_url": "https://openlegislation.uk/ionising-radiations-regulations-2017",
  "path": "schedule/7/part/2",
  "kind": "part",
  "number": "2",
  "heading": "Table of naturally occurring radionuclides (which are not processed for their radioactive, fissile or fertile properties)",
  "text": "Values for exemption from notification and registration for naturally occurring radionuclides in solid materials (which are not processed for their radioactive, fissile or fertile properties), which apply whether or not the radionuclide is in secular equilibrium with its progeny\n1 Potassium salts in quantities less than 1,000kg are exempt.\n1\n2\n3\n4\nRadionuclide name, symbol, isotope\nConcentration for: Notification (any amount of radioactive material); Registration (amounts of radioactive material that exceed 1,000kg)\nQuantity for Notification\nConcentration for Registration (amounts of radioactive material that do not exceed 1,000kg)\nRegulation 5(1) and Schedule 1, paragraph 1(a); regulation 6(2)(f)\nRegulation 5(1) and Schedule 1, paragraph 1(b)\nRegulation 6(2)(e)\n(Bq/g)\n(Bq)\n(Bq/g)\nK-401\n10\n106\n102\nRb-87\n1\n107\n104\nPb-210+\n1\n104\n10\nPo-210\n1\n104\n10\nRa-226+\n1\n104\n10\nRa-228+\n1\n105\n10\nTh-228+\n1\n104\n1\nTh-232 sec\n1\n103\n1\nU-238 sec\n1\n103\n1\nNote\nNuclides carrying the suffix “+” in the above table represent parent nuclides and their progeny as listed in the table below. The dose contributions of those progeny are taken into account in the dose calculation (thus requiring only the exemption level of the parent radionuclide to be considered).\nList of parent nuclides and their progeny as referred to in the Note above\nParent radionuclide\nProgeny\nPb-210\nBi-210, Po-210\nRa-226\nRn-222, Po-218, Pb-214, Bi-214, Po-214, Pb-210, Bi-210, Po-210\nRa-228\nAc-228\nTh-228\nRa-224, Rn-220, Po-216, Pb-212, Bi-212, Tl-208, Po-212",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/uksi/2017/1075/schedule/7/part/2",
    "retrieved_at": "2026-10-28T23:06:45.309431+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."
}