Office for Nuclear Regulation

Heysham 1 – Inspection ID: 52866

Date(s) of inspection

  • October 2023

Executive summary

Aim of inspection

To provide regulatory confidence in the implementation of the Heysham 1 Reactor 1 2023 Statutory Outage Intentions Document in relation to Mechanical Engineering.

To provide evidence to inform the ONR decision relating to the issue of a Licence Instrument for a Consent for return to service of Heysham 1 Reactor 1, on completion of the work.

Subject(s) of inspection

  • LC28 – Examination, inspection, maintenance and testing – Rating: Green

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

Site Licence Condition 30 requires EDF Nuclear Generation Limited to periodically shutdown. This is for examination, inspection, maintenance and testing of equipment important to nuclear safety.

This intervention was a Mechanical Engineering Licence Condition 28 compliance inspection. The intervention was at EDF Energy Nuclear Operations Heysham 1 during R1 Outage 027.

This report provides evidence to inform the Office for Nuclear Regulation’s decision regarding the issue of a Licence Instrument for consent to return to service for Heysham 1 Reactor 1. This is in accordance with Licence Condition 30.


Based on my sampling undertaken during this intervention, I consider that EDF NGL has adequately demonstrated its Mechanical Engineering Examination, Maintenance, Inspection and Testing implementation and arrangements

Therefore, during the Heysham 1 Reactor 1 periodic shutdown, I consider the licensee has adequately demonstrated compliance with Licence Condition 28

From my sample of evidence and plant walkdown, I have not identified any issues what would prevent Heysham 1 Reactor 1 from returning to service. I judge that a green inspection rating is appropriate.