The Ionising Radiations Regulations 2017

Regulations 2(4), 6(2)and Schedule 1

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	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)
(1) Potassium salts in quantities less than 1,000kg are exempt.
K-40(1)	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