Office for Nuclear Regulation

Sizewell B - LC22 and LC26 inspections

Executive summary

Purpose of Intervention

The purpose of this intervention was to undertake licence condition (LC) compliance inspections at EDF Energy Nuclear Generation Limited’s (NGL) Sizewell B Power Station, in line with the ONR’s Operational Facilities Division intervention strategy. The intervention was carried out by the ONR site inspector, supported by a number of specialist inspectors.

Interventions Carried Out by ONR

We performed two inspections to evaluate compliance with Licence Condition 22 (LC22) – Modifications or experiments on existing plant and Licence Condition 26 (LC26) – Control and Supervision of Operations. 

This intervention record also captures the findings from the Sizewell B’s Annual Review of Safety Security and Environment, which was conducted on the 12 February 2019 attended by the ONR delivery lead for operating reactors and inspectors from the Environment Agency.

The intervention was performed in line with ONR's guidance requirements (as described in our technical inspection guides) in the areas inspected.

Explanation of Judgement if Safety System Not Judged to be Adequate

Not applicable – no system based inspections were completed during this intervention.

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

LC26 – Control and Supervision of Operations

Our inspection of control and supervision, focused on the standards of control room alarm management at Sizewell B and involved inspectors observing activities in the main control room, discussions with staff and examination of data. We concluded that the standards of alarm response, shift handover and briefing were consistent with relevant good practice. We judged that a Green inspection rating was appropriate against LC26. A minor area for improvement was noted against NGL’s corporate arrangements for Alarm Management. NGL agreed to review these arrangements and implement improvements if necessary. This commitment will be managed via an entry on the ONR issues database.

LC22 – Modifications or experiments on existing plant

We selected a number of modifications that have changed status within the last twelve months for sample inspection, focusing on the implementation, return to service of plant and closeout of modifications. We confirmed that documentation for the implementation, return to service of plant and closeout of the modification had been prepared in accordance with NGL’s arrangements. We judge these documents had been subject to review and approval by competent staff consistent with ONR’s expectations for LC22.  We judged that, on the basis of the modifications and urgent modifications sampled, modifications are being appropriately categorised at Sizewell B. We judged that a Green inspection rating was appropriate against LC22. 

Annual Review of Safety, Security and Environment

At the Annual Review of Safety and Security, the station provided a comprehensive review of the station’s performance over the past 12 months and improvements implemented over that period.  The station lead team also explained the key focus areas within the station business plan over the coming period. ONR acknowledged the safety and security improvements which have been implemented on the station.

Conclusion of Intervention

There are no findings from this intervention that could significantly undermine nuclear safety. At present, no additional regulatory action is needed over and above the planned interventions at Sizewell B Power Station.