Office for Nuclear Regulation

LC17; Manufacturing and Testing Activities - Penetrations (MSC 29)

Executive summary

Purpose of Intervention

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, to ensure that NNB Generation Company (HPC) Ltd (NNB GenCo) is proportionately and adequately developing and implementing its licence condition (LC) compliance arrangements commensurate to the current stage of the project.

Interventions Carried Out by ONR

This one day intervention was undertaken to examine the adequacy of NNB GenCo’s implementation of its LC17 compliance arrangements. The intervention was undertaken in order to gain confidence that the electrical penetration assemblies have been subject to an appropriate manufacturing and test regime, such that they are able to fulfil the safety case requirements associated with the equipment.

LC17 requires the licensee to make and implement adequate quality management arrangements in respect of all matters which may affect safety and the following guidance was utilised:

Explanation of Judgement if Safety System Not Judged to be Adequate

N/A as this was not a safety systems inspection.

Key Findings, Inspector's Opinions and Reasons for Judgements Made

NNB GenCo and its counterparts in Direction Industrielle (DI) provided a clear demonstration of how they manage oversight of the manufacturing and testing of electrical penetration assemblies to ensure that the equipment complies with the specification and is capable of performing its safety related duty.

NNB GenCo provided evidence to show that it has appropriate understanding of manufacturing and test requirements and the role that DI play in ensuring the electrical penetration assemblies are subjected to appropriate tests and the results are acceptable.

ONR observed that NNB GenCo and DI demonstrated a questioning attitude when holding discussions with Mirion.

A number of minor concerns were noted with regard to the status of documentation relevant to the manufacturing and testing of the electrical penetration assemblies, and, at the time of writing this report, it was unclear whether the administrative procedures used to control documentation were appropriate. I will undertake follow up investigations on the adequacy of the administrative controls being applied, as part of my routine interactions with NNB GenCo, and I will provide feedback to relevant ONR personnel. 

I do not consider that the concerns regarding the administration of document control in this instance raises concerns over NNB GenCo’s demonstration of its management of the electrical penetration assembly manufacturing and test process.

Conclusion of Intervention

I judge that overall an inspection rating of GREEN (no formal action) is appropriate for licence condition 17, management systems.  This is because I found NNB GenCo to be compliant with its legal duties with only minor areas for improvement.