Executive summary
Date(s) of inspection: September 2024
Aim of inspection
This inspection assessed whether the non-computerised safety system (NCSS) V2.0 testbay tickets/non-conformances have been adequately considered and whether learning had been incorporated ahead of the NCSS V2.1 testbay campaign.
The inspection also assessed the adequacy of the processes being implemented at the V2.1 testbay and for ensuring that safety related activities are performed by competent personnel.
The NCSS has been targeted for this intervention due to its nuclear safety significance (Class 2) and that the platform it is built on (UNICORN) is a first of a kind, designed specifically for HPC. The Class 2 NCSS was sampled in favour of the Class 1 non-computerised HVAC system (NCHICS) due to the relative maturity of the testbay programme for the two systems at the time of the inspection.
Subject(s) of inspection
- LC12 - Duly authorised and other suitably qualified and experienced persons - Rating: GREEN
- LC14 - Safety documentation - Rating: GREEN
- LC17 - Management systems - Rating: GREEN
Key findings, inspector's opinions and reasons for judgement made
The non-computerised safety system (NCSS) is being supplied by TechnicAtome (TA). The NCSS version (V) 2.1 will be the final version of the system subjected to full factory acceptance testing (FAT) for handover to Framatome and delivered to site.
The NCSS V2.0 is a de-risking activity and applying lessons learned from the V2.0 campaign provides confidence that the V2.1 test results will be appropriately robust to support the overall safety justification for the Hinkley Point C (HPC) back-up I&C system.
Based on the evidence sampled during this inspection against LCs 12, 17 and 14, I found the arrangements for testing the NCSS at test bay to be appropriate and that prerequisite activities had been adequately implemented.
The inspection reviewed processes and sampled records relating to test bay team personnel qualifications and experience, requirements traceability, ticket and non-conformance report (NCR) process, the control of test bay test configuration, and test results. This sampling, and the associated discussions, provided confidence that the arrangements are comprehensive, robust, well understood and are being followed in practice. Throughout the inspection I observed a good level of knowledge from all staff involved.
I made observations under LC 14 regarding an issue with the validation tool for the generation of check sums used for traceability of the test scenarios and validation reports. Also, a need to formalise the process for the verification of test scenarios used for validation. I have raised regulatory issue RI-12236 to track the commitments for the licensee to address these observations prior to the start of the V2.1 campaign at test bay.
The licensee demonstrated openness and a good knowledge of the system and activities at test bay in response to questions thereby providing regulatory confidence.
Conclusion
Based on the areas sampled, I consider the licensee has implemented adequate arrangements for the production and assessment of safety cases with specific regard to the validation testing of the HPC NCSS V2.0 at test bay.
I judge that an inspection rating of GREEN (no formal action) is appropriate for LC12: duly authorised and other suitably qualified and experienced persons. This is because I am content with the SQEP arrangements in place and the clarification provided regarding those who are SQEP to provide training. In addition, as part of fulfilling their intelligent customer role, an area of good practice is the embedding of NNB and EDF staff at TA.
I judge that an inspection rating of GREEN (no formal action) is appropriate for LC14: safety documentation. I consider there is adequate safety documentation for the validation performed at V2.0. Resolution of the issues identified during the inspection will be required to be addressed ahead of the V2.1 campaign. These will be monitored through the level 4 regulatory issue RI-12236.
I judge that an inspection rating of GREEN (no formal action) is appropriate for LC17: management systems. This is because there are robust processes in place for performing the validation and the management of anomalies identified during the V2.0 campaign.