Office for Nuclear Regulation

Hinkley Point C – Inspection ID: 52640

Executive summary

Date(s) of inspection:

  • July 2023

Aim of inspection

In accordance with the Office for Nuclear Regulation’s (ONR’s) Hinkley Point C (HPC) construction inspection plan, ONR performs a series of planned compliance inspections of identified licence conditions (LC) and other applicable legislation, to ensure that NNB Generation Company (HPC) Ltd (NNB GenCo) is meeting its legal requirements.  The purpose of this inspection was to confirm that NNB GenCo has implemented its arrangements for LC 28 (examination, inspection, maintenance and testing) to ensure systems, structures and components are appropriately preserved and maintained prior to handover for the next phase of the project.

The overall purpose of LC 28, is to ensure that all plant which may affect safety, receives regular and systematic examination, inspection, maintenance and testing (EIMT). The purpose of this EIMT is to ensure the nuclear plant remains capable of performing its safety functions, with the required level of reliability.

At this stage of the HPC project, the LC 28 arrangements are to ensure that the plant is adequately looked after and protected so that it is capable of discharging its future nuclear safety function.

Subject(s) of inspection

  • LC 28 – Examination, inspection, maintenance and testing – Rating: GREEN

Key findings, inspector’s opinions and reasons for judgement made

The licensee, NNB GenCo, provided information on the implementation of its arrangements for the preservation and maintenance of systems, structures and components following shipment from the factory, after construction and/or installation. This covered the arrangements for the passing of requirements to contractors, how these are translated into instructions and how those are recorded and controlled.

The use of appropriate information technology (IT) tools such as, Asset Suite 9, is being progressed as a pathfinder for the latter stages of the project. Asset Suite 9 is intended to be the tool to act as a single source of all care and maintenance activities in the future, but is not in place across all contractors at present and information will need to be ported into it at a later date from lagging contractors.

Current activities were judged to be adequate and the progress made by the care and maintenance team was noted. This will be monitored through normal business via routine level 4 interactions.

Organisation for the oversight of care and maintenance through a working group was sampled. The structure of this group was judged to be adequate and its operations will be monitored through normal business.

The walkdown performed showed a good understanding of the need for care and maintenance of installed plant. No significant concerns were observed. However, areas for improvement were identified in terms of foreign materials exclusion and an area of good practice was observed in protection from welding spatter.


For the sample taken, the arrangements for care and maintenance of plant at Hinkley Point C were judged to be adequate. This is in terms of plant awaiting installation, being installed and following installation. Minor observations were made that will be followed up as part of normal business. I judge that this inspection should be rated GREEN (no formal action) against Licence Condition 28: examination, inspection, maintenance and testing.