Executive summary
Date(s) of inspection:
September 2025
Aim of inspection
The NRS Dungeness A site has been selected for an IRR17 Public Exposure inspection because the current radiation doses (2024) to the most exposed member of the public (in this case direct shine dose to workers on the adjacent EDF Dungeness B site) are above the ONR Basic Safety Objective (BS0) 20 micro sieverts per annum, Safety Assessment Principle (SAP). The Ionising Radiations Regulations 2017 (IRR17) Regulation 12(3) introduces a duty on employers to estimate doses to members of the public, in addition to the duty to restrict exposures under Regulation 9.
Subject(s) of inspection
- IRR17 - Rating: GREEN
Key findings, inspector's opinions and reasons for judgement made
The purpose of this inspection was to evaluate Nuclear Restoration Services Ltd’s arrangements at Dungeness A for complying with the Ionising Radiation Regulations 2017, Regulations 9 and 12, Restriction of Exposure and Dose Limitation, specifically in regard to members of the public.
The inspection included consideration of Nuclear Restoration Services Ltd’s written arrangements, examination of the TLDs placed at the perimeter fence, inspection of external shielding structures and interviews with staff.
The inspection was undertaken and rated against published guidance on regulatory expectations, as set out in IRR17 ACoP and Guidance (L121). Based on the evidence sampled at the time of the intervention against Nuclear Restoration Services Ltd Dungeness A’s arrangements, ONR judged that Nuclear Restoration Services Ltd demonstrated adequate compliance with the Ionising Radiation Regulations 2017 Reg 9 and 12.
Conclusion
I noted that all the weather resistant cases for the dosimeters at the survey point locations were in adequate condition.
I saw that a number of shielding structures including moveable A frames and concrete block work are in place around the B106 an B134 areas to reduce off-site radiation shine.
I noted that the background dose rate for the NRS DNA was obtained from off-site measurements. I consider this an adequate method to obtain the representative background radiation dose for the annual return.
I noted that the site only records gamma direct shine dose rates. The site should undertake neutron dose assessment at the site perimeter to aid assessing dose rates to the most representative person, which is appropriate for the radiations from this site. I have raised a regulatory issue for this matter (RI-12797).
Overall, I am satisfied that public exposure due to direct radiation exposure from the site is reduced to as low as reasonably practicable.
I judged NRS DNA implementation of IRR17 Regulation 12 (3) arrangements to be adequate to reduce doses to the public from the site operations in the areas inspected and I assign a rating of GREEN.