Office for Nuclear Regulation

Category: Sizewell B – EDF Energy Nuclear Generation Ltd

Sizewell B – Project Assessment Report (PAR): PR-01033

November 14, 2023 -


Sizewell B – Inspection ID: 52755

October 17, 2023 - Executive summary Date(s) of inspection: July 2023 Aim of inspection ONR raised RI-11069, following the July 2022 extreme ambient temperature (EAT) event. The closure strategy for RI-11069 includes undertaking inspection activities to assess the adequacy of EDF NGL’s arrangements for managing risks from EAT. Inspections are an essential element of ONR’s interventions on nuclear licensed sites. […]


Sizewell B – Inspection ID: 52804

August 14, 2023 - Executive summary Date(s) of inspection: June 2023 Aim of inspection Observation of the annual level 1 demonstration exercise to confirm that Sizewell B’s emergency arrangements remain effective. Subject(s) of inspection LC 11 – Emergency arrangements – Rating: GREEN Key findings, inspector’s opinions and reasons for judgement made ONR observed and assessed the level 1 emergency […]


Licensee representatives gather for CNI-themed inspection engagement day

May 19, 2023 - The next CNI themed inspection focuses on climate change


Sizewell B – Inspection ID: 52073

May 16, 2023 - Executive summary Date(s) of inspection: March 2023 Aim of inspection To meet the requirements of the Sizewell Statutory Outage Project as defined in the ONR Outage Inspection Plan. To provide regulatory confidence in relation to RP and compliance with Ionising Radiations Regulations 2017 (IRR’17). To inform the ONR decision relating to the issue of a […]


Sizewell B – Inspection ID: 52090

May 9, 2023 - Executive summary Date(s) of inspection: February 2023 Aim of inspection ​​​​​​​This report records the findings of an intervention visit to the Sizewell B Nuclear Power Station during the 2023 periodic shutdown. The intervention was undertaken to confirm the adequacy of the work conducted by the licensee, EDF Energy Nuclear Generation Limited (NGL), to comply with […]


Sizewell B – Inspection ID: 52158

April 28, 2023 - Executive summary Date(s) of inspection: March 2023 Aim of inspection Purpose To support ONR’s permissioning of Sizewell B return to service from RO18, ONR chemistry inspectors are seeking to conduct an inspection of significant chemistry related outage activities and off-load chemistry control. Approach The inspection will seek to sample safety relevant systems where there is […]


Sizewell B – Inspection ID: 52177

April 28, 2023 - Executive summary Date(s) of inspection: March 2023 Aim of inspection This inspection will consider aspects of the Sizewell B (SZB) refuelling outage (RO) 18 activities undertaken. This was a planned intervention and part of the 2022/2023 ONR integrated intervention strategy for operating reactors. Subject(s) of inspection LC 28 – Examination, inspection, maintenance and testing – […]


Sizewell B – Inspection ID: 51250

April 28, 2023 - Executive summary Date(s) of inspection: March 2023 Aim of inspection The aim of this intervention was to undertake a planned licence condition (LC) compliance inspection of LC 8 (warning notices) at Sizewell B. This inspection was undertaken as part of a series of planned inspections described in the Integrated Intervention Strategy for Sizewell B. Subject(s) […]


Sizewell B – Inspection ID: 51251

April 28, 2023 - Executive summary Date(s) of inspection: March 2023 Aim of inspection The aim of this intervention was to undertake a planned licence condition (LC) compliance inspection of LC 9 (instructions to persons on the site) at Sizewell B. This inspection was undertaken as part of a series of planned inspections described in the Integrated Intervention Strategy […]