Office for Nuclear Regulation

Sellafield – Inspection ID: IIS-50661

Executive summary

Date(s) of inspection:

  • November 2022

Aim of inspection

In accordance with the Office for Nuclear Regulation’s (ONR’s) Sellafield Strategy, each year ONR performs a series of planned compliance inspections of selected licence conditions, targeted at those facilities with significant importance to nuclear safety. One such inspection was undertaken to assess the National Nuclear Laboratory’s compliance with Sellafield Limited’s corporate arrangements for Licence Condition 12 (Duly authorised and other suitably qualified and experience persons) and 26 (Control and Supervision of Operations) on 8 and 9 November 2022.

Subject(s) of inspection

  • LC 12 – Duly authorised and other suitably qualified and experienced persons – RAG rating:  Green
  • LC 26 – Control and supervision of operations – RAG rating:  Green

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

This inspection consists of discussions with NNL staff, review of records and observation of the Plant Operations Control Centre (POCC) daily meeting, a subsequent setting to work briefing and an operational activity pre-job briefing.

For LC12, I sampled the training records and assessment pack of the duty DAPs in Area 200, 400 and 500. I was content that the DAPs were all in date with their required training. I discussed with the training manager the various stages of the DAP assessment and sampled relevant documents; I noted that NNL required the DAP candidates to undertake 15 training modules and be assessed by a suitable panel at the end of each module before appointment by NNL and endorsement by the Operations Control Manager (OCM). I consider NNL’s DAP appointment process suitably challenging and robust. I tested safety case knowledge, plant condition understanding, duties of control and supervision of the Area 400 DAP. From the discussions, I was content that the DAP had a good understanding of the plant operational safety case and her role and was able to discharge her responsibilities effectively.

For LC26, I attended the daily POCC, observed the subsequent setting to work for Area 400 and 500, and observed an operational activity in Area 400 starting from pre-job briefing. For the POCC, I was content that the duty DAP presented a good overview of the status of the plant and confirmed with other DAPs on the tasks for the day. I noted that the nuclear safety dashboard (NSD) highlighted conditions and outages of the plant in amber; however, no indications of the status of the open Plant Modification Proposals (PMPs) or open Conservative Decision Making (CDM) / Operational Decision Making (ODM) actions were provided. I provided regulatory advice for NNL to consider incorporating these into the NSD. Notwithstanding this, I consider the POCC was delivered effectively.

I noted that the subsequent setting to work for Area 400 and 500 clearly identified the task supervisor and team members for each task and their SQEP status was verifiable from the SQEP sheet on the information board. I was content that NNL had adequate control in setting to work.

I observed the pre-job briefing for metallography in Area 400 which required a high level of control and supervision due to the risks entailed in the job. I noted that the task supervisor delivered a very effective pre-job briefing engaging and challenging the operators’ understanding of the hazards, risks and mitigations associated with the task. I consider it a good practice to ensure safe delivery of the work by focussing the minds of the team members on safety.

I sampled NNL’s assurance plan for periodic task observation and reviewed two relevant observation records. I noted that the records clearly identified positives and negatives associated with the tasks and recommended relevant actions. However, there appeared to be a lack of tracking of the close out of actions, for which I provided regulatory advice.


On the basis of the evidence sampled at the time of the inspection, I judge that, on balance, NNL Central Lab has adequately implemented Sellafield Limited’s arrangements for LC 12 and 26. Noting the ONR guidance on inspection ratings, it is my opinion that an inspection rating of Green (no formal action) is appropriate.