Office for Nuclear Regulation

Rolls-Royces Submarines Limited’s (RRSL) – Inspection ID: 50428

Executive summary

Date(s) of inspection:

  • August 2022

Aim of inspection

The aim of this inspection is to seek confidence that RRSL has made and implemented adequate arrangements or provisions with respect to Licence Conditions 2, 8, 9 and 16. These licence conditions describe the extent and layout of the nuclear licensed site, the location of hazardous facilities, as well as provisions for the general safety of people on the nuclear licensed site.

Recognising that Rolls-Royce Submarines Limited’s licensed sites are in ‘routine regulatory attention’; ONR does not consider the RRSL sites to be ‘high-hazard nuclear sites’; and LCs 2, 8, 9 and 16 are not ‘cornerstone’ licence conditions, the inspection is to be undertaken concurrently with a separate risk-informed intervention to deliver maximum value from ONR’s site presence.

Subject(s) of inspection

  • LC2 – Marking of the site boundary – Rating: Green
  • LC8 – Warning notices – Rating: Green
  • LC9 – Instructions to persons on the site – Rating: Green
  • LC16 – Site plans, designs and specifications – Rating: Green

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

The intervention was conducted on-site by the ONR nominated site inspector for the Raynesway nuclear licensed sites, supported by an External Hazard specialist inspector, utilising relevant good practice from ONR’s licence condition inspection guides for licence conditions 2, 8, 9 and 16.  The intervention was conducted concurrently with a risk-based flooding response inspection, as it was determined that these licence conditions could be inspected with minimal additional effort on the part of the ONR and RRSL.

RRSL was able to demonstrate that the nuclear licensed site is correctly physically marked, with the boundary inspected and accurately documented on relevant plans and schedules.  Those plans and schedules are updated as necessary as changes are made via due process within the existing nuclear licensed site.  An opportunity was identified to clarify that changes to the nuclear site licensed boundary can only be undertaken through a formal relicensing process (or a licence variation).

I found that on-plant emergency arrangements signage was in place and satisfactory, and this was supported by a suitable register of emergency signage which was demonstrably checked on a regular basis.  The number, location and type of emergency signage is not prescribed by a process but is determined through expert judgement.  No issues with this system were observed at this time.

RRSL’s arrangements for the suitable induction of personnel on to the site were clear and provided a proportionate method for detailing the level of induction required.  The induction process for individuals on the licensed site was acceptable.  Individuals spoken to whilst on the licensed site were able to articulate actions to be taken in an emergency.


In my opinion, RRSL has implemented adequate arrangements for licence conditions 2, 8, 9 and 16, meeting the regulatory expectations set out in the relevant inspection guides.

Based on the sample taken, I rate LC2, 8, 9 and 16 as GREEN.  I have not identified any issues significant enough to warrant raising a regulatory issue.

  • “Relevant good practice generally met, or minor shortfalls identified, when compared with appropriate benchmarks.”
  • “No significant shortfalls identified in the delivery of safety, safeguards or security functions.”