Office for Nuclear Regulation

Remote inspection of Licence Conditions 23, 24, 26

Executive summary

Purpose of Intervention

This intervention, conducted at the Rolls-Royce Submarines Limited (RRSL) Raynesway licensed site, was undertaken as part of the 2020 / 21 Integrated Intervention Strategy (IIS) plan and propulsion sub-division strategy.

Interventions Carried Out by ONR

This inspection examined RRSL’s arrangements for, and subsequent implementation of, Licence Condition (LC) 23 operating rules (ORs), LC 24 operating instructions and LC 26 control and supervision of operations.  It focussed on operations that may affect safety ongoing in the Product Assembly Building (PAB).  PAB is undergoing inactive commissioning with no current nuclear hazard to workers or the public.  The inspection is being undertaken to gain confidence that RRSL has and is implementing arrangements which will meet regulatory expectations for LC 23, LC 24 and LC 26 prior to first nuclear operations of the facility.

Improvement Notice ONR-IN-20-02 was served on RRSL in May 2020 following a contravention of LC 23(3) in the Dreadnought Production Facility (DPF).  I have taken due cognisance of RRSL’s improvement programme which impacts compliance and implementation arrangements for the LCs inspected.  Separate interventions will be undertaken to assess whether RRSL has complied with ONR-IN-20-02.

The inspection was completed remotely due to COVID-19 restrictions.  It considered RRSL’s arrangements for LC compliance, ORs derived using these arrangements and subsequent implementation via inspection of working level documentation.  I could not directly inspect the completion of work activities and independently confirm actual compliance with these LCs.  It was planned that RRSL’s Internal Regulator would observe Power Module Transport Package (PMTP) rotations trials and provide ONR with this assurance.  However, trial operations were delayed so such assurance was not available to inform the inspection.

The intervention was performed in line with ONR's guidance requirements (as described in our technical inspection guides) in the areas inspected.

Explanation of Judgement if Safety System Not Judged to be Adequate


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

The inspection found no shortfalls which, in my opinion, have the potential to challenge the delivery of identified nuclear safety functions.  In making this judgement, I have taken due consideration of the following.

RRSL current programme indicates materials with a significant nuclear hazard will not be introduced into the facility before 2023.  There is therefore adequate time for RRSL to implement improvements before any potential for nuclear safety consequence arising from PAB operations is realised.

However, the activities sampled do involve significant conventional safety hazards and / or potential for significant equipment damage as a result of human error.  A significant event during commissioning of the facility, in addition to the immediate consequence to workers, would likely impact the Dreadnought programme.

A GREEN rating is assigned for LC 23 given demonstration of how RRSL had applied its arrangements to derive limits and conditions in the interest of safety for PAB.  RRSL also articulated how it will develop arrangements via which it will ensure that operations are controlled and carried out in compliance with these ORs.  The inspection found RRSL is learning from experience and implementing systems to improve the “golden thread” from safety case to implementation.  Work is underway to refine limits and conditions to facilitate implementation and compliance in-line with regulatory expectations.  I am therefore confident that RRSL will achieve compliance with LC 23 prior to the introduction of nuclear material to the facility.

An AMBER rating is assigned for LC 24 as, whilst the sampled operating instructions had been developed in-line with extant arrangements, RRSL could not demonstrate they contained all instructions necessary for safety.  In response, RRSL committed to review, revise and seek assurance from its Internal Regulator that written instructions are adequate prior to undertaking this activity.  I found multiple gaps to relevant good practice (RGP) in how instructions were presented to operators, noting an absence of supporting guidance in RRSL’s arrangements.  RRSL acknowledge its arrangements for LC 24 compliance do not meet regulatory expectations and is in the process of developing / implementing associated improvements.  These proposals, linked to the DPF Improvement Notice, should help to close the identified shortfalls and support the development of written instructions that will broadly meet regulatory expectations.

A NOT RATED was not assigned for LC 26.  Assurance for RRSLs Internal Regulator was not available to inform this inspection and the PMTP rotation trial will now be delayed until concerns raised via this inspection are resolved.  The trial activities are classified as a “complex lift” with additional control and supervisory requirements being identified in lift plans.  I was not satisfied that these requirements had been cascaded down as specific, formalised hold points in workface documentation.  I also noted that conventional safety consequence and equipment damage risk, which could be realised during the trial, were not highlighted.  The reliance on a verbal, rather than a written, pre-job brief meant I could not confirm the communication of this important safety information via other means.  Additionally, RRSL acknowledges improvement is required to ensure sustained compliance with LC 26 and has identified improvements to close key gaps to regulatory expectations.  Whilst noting these concerns, I concluded that a formal rating for LC 26 compliance could not be supported without direct observation of control and supervision actions.

Conclusion of Intervention

On the basis of the information provided and the evidence obtained I conclude, for the activities sampled, the following.

RRSL has effectively applied arrangements under LC 23 commensurate to current PAB operations.  Improvements to LC 23 arrangements arising from ONR-IN-20-02 will be overseen via extant Regulatory Issues (RIs) 7660 and 8039.  PAB OR development and implementation will be overseen via normal regulatory business.

RRSL arrangements under LC 24 require improvement a position RRSL acknowledges.  Improvements to LC 24 arrangements arising from ONR-IN-20-02 should resolve regulatory concerns with oversight via extant RIs 7660 and 8039.  The ONR Site Inspector is satisfied with RRSL’s commitment to resolve the identified shortfalls prior to re-commencement of activities with oversight by the Internal Regulator.  He will maintain oversight via normal regulatory business.

RRSL acknowledges compliance with LC 26 requires improvement.  It’s programme arising from ONR-IN-20-02 should deliver the required improvement.  Regulatory oversight will be maintained via RI 8039.  The Internal Regulator will observe PAB activities on-restart and provide assurance as to LC 26 compliance.  ONR Site Inspector oversight will be achieved via normal regulatory business.