Two-tonne weight strikes scaffolder on nuclear project

On 13 June 2022, he was involved in scaffolding work but a hydraulic actuator, known as a ram, was not in place which meant the unsupported heavy counterweight could fall at any point.

While the contractor was measuring up, the unsupported counterweight suddenly fell from a cooling water pump, striking Dell’s hand and then his foot, and leaving him trapped. He sustained serious injuries to his left foot including broken and amputated toes, for which he was taken to hospital where he remained for four days.

Life-changing injuries

His injuries have been described as life-changing and he has been unable to return to work as a scaffolder. He has also been diagnosed with post-traumatic stress disorder.

This incident was a conventional health and safety matter, and there was no radiological risk to the public.

Both EDF and Trillium Flow Services Ltd pleaded guilty to an offence under Section 3(1) of the Health and Safety at Work etc Act 1974 for failing to ensure the health and safety of workers, in relation to the risks arising whilst undertaking maintenance and repair work.

District Judge Stephen Leake ruled EDF must pay a fine of £533,333 and Trillium Flow Services Ltd was handed a fine of £100,000, along with prosecution costs of £15,034 each. 

‘Wholly avoidable’

After the hearing, Dan Hasted, ONR’s director of regulation - Operating Facilities Directorate, said: “We welcome the outcome which recognises that EDF and Trillium Flow Services Ltd failed in their duty to protect a worker from a known risk.

“This accident was wholly avoidable. Nobody should go to work and not come home in a fit and healthy state.

“We conducted a thorough investigation which identified significant shortcomings by EDF and Trillium Flow Services Ltd, specifically their failure to follow the correct sequence for refitting the valve which resulted in the injuries to Mr Dell.  

“We concluded that there were several missed opportunities that could have prevented this accident occurring.”

Dungeness B, which ended its power generation activities in June 2021 and is now in the defuelling stage, has four main cooling water pumps which provide seawater to the main condensers. Each of these pumps is fitted with a discharge valve.

Those valves are driven by hydraulic rams, and if the power supply is lost to the ram, a counterweight closes the valves.  

‘Fundamental misunderstanding’

But following maintenance work to remove a valve, a replacement ram was then not put in place, described by ONR as a “basic and fundamental misunderstanding”, which “created a risk… [of a] two-tonne counterweight moving and potentially injuring or killing anyone who was working in its potential path”.

ONR’s investigation revealed a number of significant failings on the part of EDF in the lead-up to the accident and a lack of learning from a similar incident at Dungeness B in 2006.

The regulator also discovered shortfalls in EDF’s planning and resources, with employees being asked to fulfil roles outside their technical capabilities and tasks being undertaken without the correct signed approvals.

Measures to reduce risks were not taken and the company’s health and safety practices fell far below appropriate standards, ONR found.

Insufficient risk assessment

Similarly, ONR also found that Trillium Flow Services Ltd was responsible for multiple failings. These included an unsuitable and insufficient risk assessment, a team relatively inexperienced in working on the main counterweight valves at the site, a lack of understanding of the operation of the valves, and evidence of ill-informed decision-making.

Hasted added: “EDF and Trillium Flow Services Ltd fully cooperated with us throughout our investigation and we welcome their guilty pleas.

“The safety of workers at nuclear facilities is absolutely paramount and we will continue to hold the UK nuclear industry to account to protect workers and the public.”

As part of the judge’s sentencing determination, he ruled the health and safety breach fell into the medium culpability category and a level 3 harm category for both defendants, with EDF classed as a “very large organisation” and Trillium Flow Services Ltd also a “very large organisation”.