- Site: Devonport
- IR number: 21-021
- Date: May 2021
- LC numbers: 23, 24, 26
Executive summary
Purpose of Intervention
This intervention, conducted at the licensee’s (Devonport Royal Dockyard Limited - DRDL) Devonport site, was undertaken as part of the 2020/21 intervention plan and propulsion sub-division strategy.
Interventions Carried Out by ONR
The inspection examined the adequacy of DRDL’s arrangements and subsequent implementation for Licence Condition (LC) 23 operating rules (ORs), LC 24 operating instructions and LC 26 control and supervision. It focussed on mobile crane operations that may affect nuclear safety which were ongoing on the licensed site.
I also conducted a walk round of the Submarine Refit Complex (SRC) to inspect improvements implemented in response to Regulatory Issues (RI) 7828.
The visit was also used to undertake an assessment of the adequacy of DRDL’s arrangements for compliance with COVID-19 social distancing and other health protection measures, and the implementation of these measures on site.
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
Not applicable.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
The inspection found the licensee demonstrated the following.
- Clear articulation of safety case derived ORs applicable to mobile crane operations and demonstration how compliance with the associated Limits and Conditions (LACs) necessary for nuclear safety is ensured at all times.
- How it has developed a suite of procedures and checklists which provided personnel with instructions necessary to ensure that ORs are implemented.
- Articulation of expectations for the control and supervision of mobile crane operations and how these are supplemented by lift planning activities.
- How Intelligent Customers (ICs) ensure compliance with safety case derived limits and conditions across the licensed site.
Direct observation of a mobile crane lift provided confidence that operations are carried out in accordance with written instructions and that control and supervision, commensurate with nuclear safety risk and significance, is implemented.
No matters were identified as requiring immediate regulatory attention during the conduct of the compliance inspection.
Finding implementation of LC 23, LC 24 and LC 26 arrangements to be broadly in accordance with regulatory expectations, inconsistency in the format and content of some LACs, and the written instructions via which they are implemented, across the site was observed. The site wide mobile crane justification (in development), and subsequent implementation via modification of associated safety cases, provides DRDL the opportunity to improve the consistency and usability of its safety management arrangements for mobile crane operations across the licenced site.
The incomplete IC coverage across the licensed site, and the potential for an ill-conceived or implemented lift to lead to nuclear consequence, had been a significant concern to ONR prior to this inspection. ONR welcomes the introduction of the Cross-Site (X-Site) IC role and how, in addition to extant 9 Dock and SRC ICs, which now provides complete oversight of lifting activities across the entirety of the licenced site. Whilst an individual is in position, the X-Site IC role is yet to be formally implemented and written instructions are still in development. A Level 4 RI will be raised to oversee implementation of this role in an effective and timely manner.
In judging written instructions adequate, some scope for improvement was identified. The most beneficial relates to supporting the checks completed by ICs to confirm that the mobile crane is configured so safety functions will be delivered on demand. DRDL committed to implement these and other improvements to instruction content and format. ONR will sample revised operating instructions as part of its assessment of the site wide mobile justification and subsequent inspection of readiness.
The extant arrangements appear to be a solid base on which site-wide mobile crane arrangements can be developed. Concerns remain regarding the usability of the justification document set and the extent to which it derives ORs which meet regulatory expectations (directly measurable or observable parameters, demonstrably unambiguous, etc.). Further information, specifically the Guidance Document, which ONR believes to be a key component of the “golden thread”, is required to confirm an adequate suite of LACs to ensure nuclear safety. DRDL agreed to share this information but could not provide a definitive timescale as to when this will be.
The SRC walkthrough provided confidence that DRDL had implemented a suite of improvements in response to RI 7828 which should reduce the risk of dockside crane slew limits being challenged in the future. It was not possible to verify that that DRDL had completed all its commitments and further interventions will be required to be completed prior to close out of this RI.
DRDL’s COVID-19 arrangements were judged to be in compliance with government guidance in relation to working safely during the pandemic in factories, plants and warehouses. The arrangements continue to be judged as effectively implemented.
Conclusion of Intervention
No shortfalls or issues were found which significantly affect nuclear safety or were judged to be of such regulatory concern as to require immediate action.
Overall, the licensee’s implementation of its arrangements for LC 23, LC 24 and LC 26, in regard to mobile crane operations, was judged to be broadly in-line with regulatory expectations. A GREEN (no formal action) rating was assigned against each LC. A Level 4 RI will be raised to oversee timely formalisation of the X-Site IC role and associated compliance arrangements. Noting scope for minor improvements and resolution of inconsistencies across the site, ONR judged DRDL’s extant arrangements as a suitable and sufficient basis on which the new suite site-wide mobile crane arrangements can be developed.
DRDL’s compliance with COVID19 social distancing and other health protection measures continues to be adequate with effective implementation across the site.