The UK Office for Nuclear Regulation (ONR) has set out a significant programme of reform designed to speed up nuclear project delivery across the UK. This was in response to a letter from the Chancellor on the implementation of the Nuclear Regulatory Review 2025 conducted by the Nuclear Regulatory Taskforce, which recommended a “radical reset” of the UK’s nuclear industry. The Review made recommendations aimed at lowering costs, streamlining judicial reviews, and reducing the timeframes needed to deliver major civil and defence nuclear infrastructure projects.
In his letter to Chancellor of the Exchequer John Healey, ONR CEO and Chief Nuclear Inspector Mike Finnerty described how the regulator is transforming its approach to keep pace with a rapidly growing nuclear sector, while continuing to maintain strong safety, security and safeguards standards.
“I fully support the Review’s conclusions that radical reforms are needed. I have instructed my teams to focus on a more outcomes-based regulatory system, without compromising our role to protect people and the environment,” said Finnerty. “The radical reforms we are implementing will maintain robust oversight where hazards are greatest, but will also reduce unnecessary bureaucracy, strengthen professional judgement and provide greater regulatory certainty to enable industry to accelerate its programmes.”
Central to this transformation is ONR Together, a new rolling strategy for becoming a more modern, agile and productive organisation. Finnerty said that, through this strategy, ONR is embedding changes designed to strengthen accountability, professional judgement and organisational effectiveness. “I have carefully selected and strengthened the executive leadership of ONR, bringing together leaders with the mindset, capability and determination required to deliver meaningful change. Together, we will drive transformational change across ONR, ensuring the organisation is equipped to meet future regulatory demands with pace, agility and impact,” he explained.
ONR has also created a Lead Nuclear Regulator Group (LNRG) strengthen coordination between regulators, reduce duplication, and enable issues to be identified and resolved earlier across major programmes. Work is underway to implement Lead Regulator Models (LRMs) for Generic Design Assessment (GDA) and Low Level Waste Repository (LLWR) programmes, while early engagement with a major defence project is helping to test the model and demonstrate its potential benefits.
ONR has established an Industry CEO Forum bringing together senior leaders from across government, industry and regulation to tackle the behaviours that contribute to unnecessary delay or hinder progress, encouraging a more collaborative and outcomes-focused approach to delivery. “By strengthening collective accountability, sharing lessons and addressing systemic barriers, leaders can improve decision making, build organisational resilience and support the timely delivery of nuclear projects while maintaining the highest standards of safety, security and public trust,” Finnerty noted.
Revised safety case guidance has been published to help industry produce clearer and more proportionate safety arguments without compromising standards. “We are driving a fundamental transformation of ONR’s regulatory framework and delivery model to enable faster, more effective and more proportionate regulation,” he said. “Through modernised Safety Assessment Principles (SAPs), streamlined safety case guidance, enhanced use of data and digital technologies, and more consistent decision-making, we are creating a regulatory system that is clearer, more predictable and focused on the issues that matter most.”
This includes championing a step change in safety case practice, moving away from unnecessarily complex and voluminous documentation towards concise, evidence-based safety arguments focused on significant risks and effective controls. “By combining risk-informed decision-making with digital and data-enabled regulation, we will improve assessment efficiency, identify emerging risks earlier, target regulatory effort where it adds greatest value, and reduce unnecessary burden on dutyholders,” Finnerty said.
“Alongside this, we are modernising our regulatory approach through greater use of risk-informed decision making, increased proportionality and clearer expectations, including recognising proven technologies and operating experience where appropriate. This includes adopting a more agile, collaborative and transparent approach to GDAs, maintaining momentum on high-hazard risk reduction at Sellafield and supporting new fuel manufacturing capability, while focusing regulatory effort on activities that deliver demonstrable safety improvements.”
He added: “We are also driving greater alignment across government, industry and international partners to support fleet-based approaches for European Pressurised Reactors and small modular reactors, to strengthen the nuclear supply chain, expand international collaboration and enable the safe, timely delivery of critical civil and defence nuclear programmes. Enhanced use of data and digital tools will further improve planning, prioritisation and oversight, while maintaining robust standards and providing greater certainty for investors and developers.”
ONR is supporting government proposals for a Commission for Nuclear Regulation, will improve coherence, transparency, accountability and pace of delivery across the sector while maintaining standards and regulatory independence. “Building on the integration of civil and defence nuclear regulation within ONR, this model could reduce complexity for investors and operators while strengthening system-wide effectiveness.”
ONR commissioned an independent initial economic assessment to evaluate the potential savings arising from the recommendations of the 2025 Review. “Our recent experience demonstrates the benefits that can be achieved through international collaboration and improvements to regulatory processes,” Finnerty noted. “For example, the most recently completed two-step GDAs for the GE Vernova Hitachi BWRX-300 and Holtec SMR-300 realised substantial efficiencies compared with equivalent stages of previous GDAs. Resource deployment was reduced by more than 35%, while maintaining the same scope and level of regulatory rigour. As a result, both GDAs were delivered several million pounds under budget.”
The assessment also indicated that work to clarify and embed simpler, more proportionate expectations for the development and assessment of safety cases, together with the review and revision of regulatory guidance, could deliver significant longer-term benefits. By eliminating duplication, reducing unnecessary analysis and restoring safety cases to practical documents that directly support dutyholders’ operations, these reforms will help focus resources on the most significant risks. They should also support faster and more efficient project delivery across the nuclear sector.
“In addition, the independent economic assessment identifies clear potential for both the lead regulator model and increased international collaboration to generate material annual savings for industry. These benefits are expected to arise through shorter and more predictable assessment timelines, lower regulatory charges, and reduced costs for requesting parties. The assessment suggests that the greatest savings are likely to come from improved efficiency, greater predictability, and a reduced regulatory burden across the sector.”
