Office for Nuclear Regulation

ONR compliance inspection: commissioning of Dry Fuel Store Process

Executive summary

Purpose of intervention

This Office for Nuclear Regulation (ONR) inspection was carried out to support ONR’s assessment and permissioning of EDF Energy Nuclear Generation Ltd (NGL) Sizewell B Dry Fuel Store project.  It focused on the adequacy of testing and commissioning arrangements for equipment and operations in support of Dry Fuel Store processing.

Interventions Carried Out by ONR

This inspection targeted a range of Nuclear Site Licence Conditions (LC) that are linked into commissioning activities:

Explanation of Judgement if Safety System Not Judged to be Adequate

This was not a planned Safety System Inspection and so no judgement was made.

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

Based on my inspection observations and findings I consider the Dry Fuel Store Commissioning Team is complying with Site’s LC 21: Commissioning Arrangements.  This is established by the production of a Commissioning Strategy and Paper of Principle setting out the Commissioning Team’s approach for conduct testing and commissioning activities that I found to have been fully implemented given equipment testing schedules and my review of test findings.  A Test Matrix, showing safety case claims for equipment and testing / commissioning activities and confirming safety functionality, had been produced which I consider demonstrates good practice.

The Dry Fuel Store Testing and Commissioning Panel is established and I found is working to the required standards based on my inspection of meeting minutes.  I identified one minor issue with the setting of roles and responsibilities for Test Team members which had not been formally implemented through written documentation.

I consider testing and commissioning work is being conducted in a safe and structured manner with testing procedures and draft operating instructions in place.  Test Team Leaders were considered to be suitably qualified and experienced persons based on my observations of tasks and informal discussions held during this inspection.  Tasks were adequately controlled and supervised by Test Team Leaders with desktop reviews undertaken in preparation of setting to work; pre-job briefs before work commenced; and monitoring of work during testing.  In my review of evidence files some Test Team Leaders did not have the length of work experience required in the Site’s LC 21 arrangements for this role.  This finding was discussed with the Dry Fuel Store Commissioning Manager who satisfied me that where this requirement had not been met he had held informal interviews with these individuals to satisfy himself that they were capable for this role.

Training packages for both commissioning and operational phases have been developed, although NGL specific training was lagging behind programme.  Roll out of training for commissioning team members was also identified as behind programme although efforts were being made to accelerate training delivery.

Conclusion of Intervention

I consider the inspection outcomes from this intervention were positive with a number of examples of good practice identified.  Expectations set in ONR guidance had been met and exceeded in some individual areas dealing with commissioning documentation.


No recommendations were identified from this inspection.