Office for Nuclear Regulation

RRSL – Level 1 Emergency Exercise

Executive summary

Purpose of Intervention

This intervention at the Rolls-Royce Submarines Ltd (RRSL) Nuclear Fuel Production Plant (NFPP) and Neptune Reactor at Raynesway, was undertaken as part of the 2018/19 intervention plan and strategy.

Interventions Carried Out by ONR

This inspection was undertaken to observed and assess the annual demonstration emergency exercise “FOSSA”.

Explanation of Judgement if Safety System Not Judged to be Adequate


Key Findings, Inspector's Opinions and Reasons for Judgements Made

A team of ONR inspectors observed the level 1 demonstration exercise “Fossa”. The aim of the exercise was to demonstrate and test RRSL’s Nuclear Emergency Arrangements in response to an event on the Raynesway site.

ONR inspectors observed examples of good practice in most aspects of the emergency exercise, and judged that RRSL would be effective in responding to a genuine emergency.

Conclusion of Intervention

It is ONR’s opinion that the Level 1 emergency response exercise satisfied the requirements of an adequate demonstration of the implementation of the nuclear emergency arrangements for the Raynesway site, in respect of LC11.  A green rating is therefore considered appropriate.