The UK Office for Nuclear Regulation (ONR) has issued an improvement notice to EDF Energy following an electrical cabling incident at its Hunterston B site in Ayrshire, Scotland. The incident occurred in November 2025, when workers failed to ensure that the electrical cabling was deployed safety while undertaking work on the cooling water valves in one of the facilities on the site.
Although no injuries were sustained, ONR said the incident presented a significant potential risk to worker safety. The improvement notice requires EDF Energy to review, revise and implement arrangements to ensure that all 415V portable equipment at Hunterston B is appropriately constructed, maintained, tested and controlled. EDF Energy must also strengthen its risk assessment processes and improve arrangements for personnel undertaking electrical work on the site.
“The safety of workers at nuclear licensed sites is a key priority for us. While no one was hurt on this occasion, the potential for serious harm was significant,” said Tom Eagleton, ONR Head of Safety Regulation, Decommissioning, Fuel and Waste sites. “It’s essential that EDF Energy implements the necessary improvements to ensure this cannot happen again.” EDF Energy is required to comply with this notice by 20 March.
