# The Ionising Radiations Regulations 2017, Part 2: Table of naturally occurring radionuclides (which are not processed for their radioactive, fissile or fertile properties)


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
1 Potassium salts in quantities less than 1,000kg are exempt.
1
2
3
4
Radionuclide name, symbol, isotope
Concentration for: Notification (any amount of radioactive material); Registration (amounts of radioactive material that exceed 1,000kg)
Quantity for Notification
Concentration for Registration (amounts of radioactive material that do not exceed 1,000kg)
Regulation 5(1) and Schedule 1, paragraph 1(a); regulation 6(2)(f)
Regulation 5(1) and Schedule 1, paragraph 1(b)
Regulation 6(2)(e)
(Bq/g)
(Bq)
(Bq/g)
K-401
10
106
102
Rb-87
1
107
104
Pb-210+
1
104
10
Po-210
1
104
10
Ra-226+
1
104
10
Ra-228+
1
105
10
Th-228+
1
104
1
Th-232 sec
1
103
1
U-238 sec
1
103
1
Note
Nuclides 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).
List of parent nuclides and their progeny as referred to in the Note above
Parent radionuclide
Progeny
Pb-210
Bi-210, Po-210
Ra-226
Rn-222, Po-218, Pb-214, Bi-214, Po-214, Pb-210, Bi-210, Po-210
Ra-228
Ac-228
Th-228
Ra-224, Rn-220, Po-216, Pb-212, Bi-212, Tl-208, Po-212

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Source: https://www.legislation.gov.uk/uksi/2017/1075/schedule/7/part/2 (the official version)
Page: https://openlegislation.uk/ionising-radiations-regulations-2017/schedule-7/part-2
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.