The Nuclear Installations (Prescribed Conditions and Excepted Matter) Regulations 2025
Source: legislation.gov.uk (2025-12-02)

Certain types of nuclear sites are subject to the nuclear third party liability (“NTPL”) regime established by the Nuclear Installations Act 1965 (“the Act”). In the event of a nuclear incident, the NTPL regime channels liability exclusively and strictly to the operator of the site responsible for the incident, however that liability is capped. The NTPL regime also requires operators of sites to have Secretary of State approved financial security arrangements in place to ensure they can meet any claims up to that cap. The Act implements the United Kingdom’s NTPL obligations under the 1960 Paris Convention on Third Party Liability in the Field of Nuclear Energy (the Paris Convention).

Statutory Instruments

2025 No. 1171

NUCLEAR ENERGY

The Nuclear Installations (Prescribed Conditions and Excepted Matter) Regulations 2025

Made

6th November 2025

Laid before Parliament

11th November 2025

Coming into force

2nd December 2025

The Secretary of State makes these Regulations in exercise of the powers conferred by sections 7C(1)(a)(iii) and 26(1) of the Nuclear Installations Act 1965(1 (\"#f00001\")).

In accordance with article 4 of, and Schedule 3 to, the Scotland Act 1998 (Transfer of Functions to the Scottish Ministers etc.) Order 1999(2 (\"#f00002\")), the Secretary of State has consulted the Scottish Ministers.

Citation, commencement and extent

1.—(1) These Regulations may be cited as the Nuclear Installations (Prescribed Conditions and Excepted Matter) Regulations 2025 and come into force on 2nd December 2025.

(2) These Regulations extend to England and Wales, Scotland and Northern Ireland.

Prescribed conditions

2.—(1) The conditions prescribed under section 7C(1)(a)(iii) of the Act are that, during the lifetime of the site—

(a)the effective dose from radiation released from the site to a member of the public off site would be no greater than 1 millisievert in any 12-month period in all reasonably foreseeable circumstances and assuming no protective or mitigating actions are taken (the dose condition);

(b)the risk of criticality occurring on the site is negligible (the criticality condition).

(2) In this regulation—

(a)“Act” means the Nuclear Installations Act 1965;

(b)“effective dose” has the meaning given by section 11H(11) of the Act(3 (\"#f00003\"));

(c)“the lifetime of the site” means the period during which the site is subject to an appropriate permit(4 (\"#f00004\")).

Amendment to the Nuclear Installations (Excepted Matter) Regulations 2017

3.—(1) The Nuclear Installations (Excepted Matter) Regulations 2017(5 (\"#f00005\")) are amended as follows.

(2) In regulation 3 (excepted matter)—

(a)in paragraph (1), for “paragraph (2) or (3)” substitute “paragraph (2), (3) or (4)”;

(b)after paragraph (3) insert—

“(4) The requirement in this paragraph is that the nuclear matter has been disposed of in an installation for the disposal of nuclear matter on an excluded disposal site(6 (\"#f00006\")).”

Vallance

Minister of State

Department for Energy Security and Net Zero

6th November 2025

Explanatory Note

(This note is not part of the Regulations)

Certain types of nuclear sites are subject to the nuclear third party liability (“NTPL”) regime established by the Nuclear Installations Act 1965 (“the Act”). In the event of a nuclear incident, the NTPL regime channels liability exclusively and strictly to the operator of the site responsible for the incident, however that liability is capped. The NTPL regime also requires operators of sites to have Secretary of State approved financial security arrangements in place to ensure they can meet any claims up to that cap. The Act implements the United Kingdom’s NTPL obligations under the 1960 Paris Convention on Third Party Liability in the Field of Nuclear Energy (the Paris Convention).

The 2004 Protocol to Amend the Convention on Nuclear Third Party Liability in the Field of Nuclear Energy (“the Protocol”) came into force on 1st January 2022, adding sites on which installations for the disposal of nuclear matter (“relevant disposal sites”) operate to the types of nuclear site subject to the NTPL regime. The changes were implemented domestically by the Nuclear Installations (Liability for Damage) Order 2016, which came into force on the same day.

However, between the Protocol being agreed and entering into force, the States Parties to the Paris Convention agreed a route for certain relevant disposal sites to be exempt from the NTPL regime when they adopted the 2016 Decision and Recommendation Concerning the Application of the Paris Convention on Third Party Liability in the Field of Nuclear Energy to Nuclear Installations for the Disposal of Certain Types of Low-level Radioactive Waste.

Section 7C of the Act and these Regulations implement the above Decision and Recommendation. Section 7C(1)(a)(i) and (ii) set out two of the necessary conditions (the permit condition and the site history condition) and regulation 2 of these Regulations prescribes two additional conditions (the dose condition and the criticality condition). A site which satisfies all four conditions is eligible to be granted excluded disposal site status, meaning it is no longer a relevant disposal site and is therefore exempt from the NTPL regime.

Regulation 3 amends the Nuclear Installations (Excepted Matter) Regulations 2017 (S.I. 2017/920 (\"http://www.legislation.gov.uk/id/uksi/2017/920\")) so that nuclear matter disposed of in an installation on an excluded disposal site is “excepted matter” for the purposes of the Act. This ensures that, when a site is exempted from the NTPL regime, responsibility does not revert to the operator of the site that the nuclear matter originated from.

A full impact assessment has not been produced for this instrument as no, or no significant, impact on the private, voluntary or public sector is foreseen.

(1)

1965 c. 57 (\"http://www.legislation.gov.uk/id/ukpga/1965/57\"). Section 7C was inserted by section 304 of the Energy Act 2023 (c. 52) (\"http://www.legislation.gov.uk/id/ukpga/2023/52\"). Section 26(1) was amended by section 32 of the Energy Act 1983 (c. 25) (\"http://www.legislation.gov.uk/id/ukpga/1983/25\"), paragraphs 16 and 26 of Schedule 12 to the Energy Act 2013 (c. 32) (\"http://www.legislation.gov.uk/id/ukpga/2013/32\"), sections 302(1) and (3) and 304(1) and (5) of the Energy Act 2023, S.I. 1999/2786 (\"http://www.legislation.gov.uk/id/uksi/1999/2786\") and 2016/562 (\"http://www.legislation.gov.uk/id/uksi/2016/562\"), and is prospectively amended by paragraph 8(1) and (2) of Schedule 22 to the Energy Act 2023. See the definition of “prescribed” in section 26(1) of the Nuclear Installations Act 1965.

(2)

S.I. 1999/1750 (\"http://www.legislation.gov.uk/id/uksi/1999/1750\"), amended by paragraph 30 of Schedule 12 to the Energy Act 2013 and S.I. 2016/562 (\"http://www.legislation.gov.uk/id/uksi/2016/562\"). There are other amending instruments, but none is relevant.

(3)

Section 11H was inserted by S.I. 2016/562 (\"http://www.legislation.gov.uk/id/uksi/2016/562\").

(4)

See the definition of “appropriate permit” in section 26(1) of the Nuclear Installations Act 1965 (c. 57) (\"http://www.legislation.gov.uk/id/ukpga/1965/57\").

(5)

S.I. 2017/920 (\"http://www.legislation.gov.uk/id/uksi/2017/920\").

(6)

See the definitions of “excluded disposal site” and “nuclear matter” in section 26(1) of the Nuclear Installations Act 1965.