Office for Nuclear Regulation

Hunterston B – Inspection ID: 51011

Executive summary

Date(s) of inspection:

  • February 2023

Aim of inspection

To confirm adequate implementation of LC7

Subject(s) of inspection

  • LC 07 – Incidents on the site – Rating: Green

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

I carried out an inspection of the implementation, at Hunterston B, of the arrangements for LC 7 ‘incidents on site’ and other associated EDF organisational learning (OL) processes.  The inspection examined the adequacy of personnel to support the OL processes and sampled reporting, categorisation, investigation and corrective actions taken in response to events.  The inspection confirmed that adequate personnel continue to support the OL process and a sample of events confirmed that events are appropriately categorised and investigated.  Some areas for improvement were identified; particularly a greater degree of learning could be extracted from some events and consideration of extent of condition for some defects and faults.  Overall I was satisfied with the level of oversight and priority given to completion of corrective actions by the station review board.

I noted that the station is dependent upon the fleet performance improvement team to deliver some aspects of the organisational learning process including access to the Organisational Learning Portal (OLP).   Continued access to the EDF OLP, post transfer of the station to Magnox, is potentially challenged by the ‘clean break’ guiding principle defined in the transfer blueprint.  This therefore will be particular focus of ONR’s assessment of Magnox’s application to manage the Hunterston B licensed site.


I was satisfied with the implementation of the LC 7 arrangements for organisational learning at Hunterston B.  I therefore rated the inspection Green (no formal action).