Executive summary
Date(s) of inspection:
December 2025
Aim of inspection
To assess compliance with the Ionising Radiations Regulations 2017 (IRR17) with regard to dose management, and the control and management of radioactive materials.
In addition, Safeguards and Security arrangements will be assessed in relation to the control and management of radioactive materials and Qualifying Nuclear Material (QNM).
Subject(s) of inspection
- FSE 3 Competence Management - Rating: Green
- FSE 7 Nuclear Material Tracking - Rating: Green
- FSE 9 Material Balance - Rating: Green
- IRR17 - Rating: Green
- NSR19 Reg03 - Declaration of basic technical characteristics - Rating: Green
- NSR19 Reg06 - Accountancy and control of qualifying nuclear material - Rating: Green
- NSR19 Reg07 - Accountancy and control plan - Rating: Green
- SyDP 6.1 - Categorisation for Theft - Rating: Green
- SyDP 6.3 - Physical Protection System Design - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
This was a joint inspection between radiological protection, safeguards and security specialists. The inspection provided suitable time to discuss arrangements with the licensee (NNB GenCo Ltd.) and key contractors, examine appropriate documents, and undertake a site visit to gain continued confidence in the management and control of radioactive material and Qualifying Nuclear Material (QNM).
Radiological Protection
The control of radioactive sources on site was inspected against the relevant requirements of the Ionising Radiations Regulations 2017 (IRR17). Additionally, restriction of exposure to ionising radiation and cooperation between employers was inspected from a radiological protection perspective. The inspection built upon previous inspections related to industrial radiography (as defined in IRR17), to ensure standards are being maintained and any learning is taken forward, particularly as the volume of radiography is planned to increase.
From a radiological protection perspective, I was content that there are suitable arrangements in place for the storage, control and accountancy of radioactive sources. Additionally, I was content that industrial radiography contractors have suitable arrangements in place to restrict exposure of both those undertaking, and those not involved in radiography operations. I therefore rated this intervention GREEN from a radiological protection perspective.
Safeguards
This intervention sought evidence that arrangements implemented at Hinkley Point C (HPC) - owned and operated by NNB GenCo Ltd. - including those relevant to safety and security expectations, were sufficient to demonstrate compliance with – and/or to enable the owners and relevant duty holders in respect of QNM on site to comply with – The Nuclear Safeguards (EU Exit) Regulations 2019 (NSR19) and with ONR’s expectations pursuant to ONR guidance for Nuclear Material Accountancy, Control and Safeguards (ONMACS) [ONR-SAF-FW-001 – Issue 6].
To inform my judgements on the adequacy of the arrangements, I utilised the Safeguards Technical Inspection Guidance (TIG) [SG-INSP-GD-001 – Issue 4]; safeguards expectations as described in ONMACS; and the ONR Organisational culture guide for inspectors [NS-INSP-GD-070 – Issue 3.2].
I visited the HPC site, held discussions with NNB GenCo Ltd. staff with safeguards responsibility, held discussions with staff representing the owners and relevant duty holders in respect of QNM on site, and sampled NNB GenCo Ltd.’s procedures and other documents relevant to the inventories and flows of QNM on site in order to make a judgement as to the sufficiency of the arrangements for safeguards on non-NNB GenCo Ltd.-owned QNM on site.
Based on the evidence I sampled during the course of the inspection, I judged that there were no significant shortfalls identified during the intervention. I judged there to be one minor shortfall against ONR’s expectations pursuant to Material Accountancy and Control Expectations (MACE) 3.3 of ONMACS; specifically, that NNB GenCo Ltd. was not able to provide written evidence of having reviewed the training material and competency assessments of the sampled contractor.
I have opened a Level 4 Regulatory Issue, RI-12887, to address this shortfall. I have also opened Level 4 Regulatory Issue, RI-12885, to address a regulatory observation regarding the status of updates to the Basic Technical Characteristics (BTC) for HPC. I am nonetheless satisfied that NNB GenCo Ltd.’s arrangements as sampled during this intervention were sufficient to meet ONR’s expectations for such. I therefore rated this intervention GREEN for the safeguards purpose.
Security
The security aspect of this planned joint purpose inspection was to assess the adequacy of security arrangements implemented at HPC for determining effective and proportionate Physical Protection Systems (PPS) for the physical protection of radiological sources relevant to the current construction phase of the HPC nuclear power station. This was to be achieved by inspecting the site and facilities’ process for applying categorisation for theft according to the quantities and forms of radioactive sources held and whether they meet the required PPS outcomes following categorisation. The inspection was carried out in response to an increased category of radiological sources, such as Cobalt 60 (Co-60), arriving at HPC site.
The inspection was carried out in accordance with the legal requirements of Regulation 7(1) of the Nuclear Industries Security Regulations (NISR) 2003 (as amended) and the regulatory expectations of the ONR Security Assessment Principles (SyAPs) 2022.
Following the inspection process and the evidence sampled, the existing arrangements implemented on HPC for categorising industrial radiography sources used and stored on site for the risk of theft in order to determine an effective and proportionate PPS for the current radiological source stores (RSS) have been judged to be adequate and regulatory expectations have been met. No regulatory concerns have been identified and no regulatory advice was given. The inspection was therefore rated GREEN from a security perspective.
Conclusion
Upon consideration of the ONR guidance on inspection ratings, I judge that a rating of GREEN (no formal action) is appropriate for this intervention.