Executive summary
Date(s) of inspection:
September 2025
Aim of inspection
To form a judgement as to the adequacy of NNB GenCo's and the mechanical, electrical and HVAC (MEH) Alliance's processes and procedures for scheduling, undertaking and modifying installation activities on-site, and their management and control of this. It will also provide assurance that NNB GenCo and the MEH Alliance are meeting the legal duties placed upon them by relevant statutory provisions, particularly their duties under the Construction (Design and Management) Regulations 2015.
Subject(s) of inspection
- CDM 15 (Client / PD / PC duties) - Rating: Green
- LC17 - Management systems - Rating: Green
- LC19 - Construction or installation of new plant - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
The inspection focused on the control and management of planning and sequencing of installation works. It sampled how both NNB and the MEH Alliance work together to mitigate risks to both personnel and the configuration of the design.
The inspection was undertaken over two days, and involved detailed discussions related to :
- Planning and sequencing
- Stakeholder engagement
- Digital tools used to manage configuration
- Control of changes in design, manufacture and during installation
- Changes in the MEH scope in terms of additional work and removal of scope
- NNB's arrangements for the management and monitoring of the MEH alliance's activities
I also considered the adequacy of NNB's arrangements in regard to its roles as Principal Designer and Principal Contractor under the Construction (Design and Management) regulations 2015 and the MEH Alliance's role as Contractor.
I judged that the planning and sequencing of installation activities is well controlled and, in many cases, implemented without issue. The control and management of configuration through non-conformances and field changes is appropriately implemented, although ONR has observed some instances where a design change has not been implementing pre-manufacture and noted at the point of installation as a non-conformance. Although this is not ideal, the arrangements that NNB and the MEH Alliance have in place have identified and addressed these. I also judged that where the MEH Alliance's scope of works is changed, it has robust arrangements in place to review and manage this, for example its Project Change Request process and work instructions related to ‘site additional scope’.
One area that could not be sufficiently answered was concerning NNB's role of Principal Designer within the UK Design Change process. Specifically this was regarding who by, how and when health and safety risks are assessed and reviewed in relation to elimination or mitigation and how these are communicated to relevant parties during construction and operation. I will follow this up at the next Installation and On-site Fabrication Assurance Level 4 meeting in October 2025 before judging whether a Regulatory Issue is required.
Conclusion
Following my inspection of NNB and the MEH Alliance's control of configuration, I judge the following:
Planning and configuration control tools used appear robust, with very good explanations and demonstrations provided by MEH teams.
NNB and the MEH Alliance demonstrated that the planning and sequencing of installation activities is well thought through, controlled and, in many cases, implemented without issue.
I was able to follow through non-conformance reports and field change requests with a clear thread.
It is positive that there is a drive to improve the look-ahead and planning within the Level 5 planning and sequencing up to the 8 week point and further out to 16 weeks.
Planning, management and monitoring of the installation works appears to be well controlled by MEH and NNB, in accordance with the duties placed on them under the Construction (Design and Management) Regulations 2015 as Principal Contractor and Contractor.
I witnessed the ‘plan of the day’ meeting, which was a well managed interaction.
One key area that we couldn’t conclude was related to the Principal Designer role under CDM within the UK Design Change process. I will follow this up at the next Installation and On-site Fabrication Assurance (IOFA) Level 4 meeting on 1 October 2025 as key people were not available during my inspection and it presents an ideal opportunity for NNB to have appropriate representation. Following this, I will judge whether a Regulatory Issue is required to monitor any improvements.
I have rated this inspection green as relevant good practice was generally met and legal duties complied with. There was also a clear drive within the project to learn from experience and implement appropriate improvements.