Office for Nuclear Regulation

Rolls-Royce Submarines Limited – Inspection ID: 52074

Executive summary

Date(s) of inspection:

  • February 2023

Aim of inspection

The visit was organised by the Office for Nuclear Regulation (ONR) as part of the Competent Authority (CA) and forms part of the annual intervention programme agreed with the facility, under the Control of Major Accident Hazards Regulations 2015 (COMAH).

The inspection was undertaken to provide regulatory confidence in the management of conventional health and safety hazards present at Rolls Royce Submarines Limited (RRSL). Namely, Control of Major Accident Hazards Regulations 2015.​​​​​​​

Subject(s) of inspection

  • COMAH – Control of Major Accident Hazards Regulations 2015 – rating: Green

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

Regulatory judgement was based on determining compliance with the COMAH Regulations 2015, the Health and Safety at Work etc. Act 1974, Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) and The Electricity at Work Regulations 1989.

CA judged notable progression regarding COMAH emergency preparedness and response has been observed, including examples of good practice. The dutyholder has demonstrated plans for ongoing development to improve major incident control and mitigation.

To underpin future work, CA recommended development of a COMAH major accident scenario overview and will track completion of a through a level 4 regulatory issue.

ONR judged that RRSL appeared to adequately control and manage electrical safety. There were some minor issues identified which RRSL either addressed immediately or undertook to clarify/address.


An inspection rating of Green, no formal action has been assigned to this intervention. This is based on dutyholder development plans, emergency response provision and electrical safety standards observed.