Executive summary
Date(s) of inspection:
August 2025
Aim of inspection
The focus of this intervention is on restriction of exposure, contingency arrangements, control of designated areas and radioactive source management associated with industrial radiography and the use of gamma radiography sources, especially the use of Co60 on the primary circuit welds, and compliance with the Ionising Radiations Regulations 2017.
The intervention is to gain continued confidence that arrangements are in place to restrict exposure and access into designated areas of those not involved in radiography operations, and there are suitable arrangements for the storage and accountancy of the radiography sources.
The intervention will also consider any radiography related event investigations undertaken and how the recommendations have been implemented.
Keys areas to be examined:
- Radiography operations site notifications and awareness – sharing of barrier plans.
- Review of the radiation risk assessments (RAMS) following learning from primary circuit radiography operations.
- Review of contingency plans following primary circuit radiography operations, and continued training.
- Observation of the control of the radiography designated area – searching, monitoring, signage and restriction of access.
- Review of dose monitoring and trending.
Subject(s) of inspection
- IRR17 - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
The inspection provided suitable time to discuss arrangements with NNB GenCo and key contractors, examine appropriate documents, and undertake a site visit to gain continued confidence in primary circuit radiography activities utilising Ir192 and Co60 gamma radiography sources, and that arrangements are in place to restrict exposure to as low as reasonably practicable (ALARP).
Additionally, contingency arrangements and radioactive source management associated the primary circuit radiography was also reviewed.
NNB GenCo do not undertake industrial radiography themselves, with the inspection focussed on the arrangements of the industrial radiography contractors undertaking this work.
The inspection built upon previous inspections related to industrial radiography, and in particular primary circuit radiography, to ensure standards are being maintained and any learning is incorporated into the appropriate risk assessments and method statements.
I was content that the industrial radiography contractors have suitable arrangements in place to restrict exposure of both those undertaking, and those not involved in the primary circuit radiography operations. Suitable contingency arrangements are in place, and these have been demonstrated, and will be further exercised before each session of primary circuit gamma radiography is undertaken.
A small number of observations were made, both positive and some requiring attention.
A number of actions were agreed at the time, and these will be followed up via normal regulatory interactions.
Conclusion
I judged that, on the basis of evidence sampled at the time of this inspection, compliance with IRR17 was demonstrated, and that doses associated with primary circuit radiography remain ALARP. An inspection rating of Green (no formal action) is appropriate.