The incident, on April 24, did not involve nuclear material or any radiological risk to employees at the nuclear fuel reprocessing and decommissioning site in Seascale, Cumbria.
The worker sustained up to 20% burns while undertaking electrical work, according to the Office for Nuclear Regulation (ONR).
Sellafield pleaded guilty on Friday at Carlisle Magistrates’ Court to an offence under Section 2 (1) of the Health and Safety at Work etc. Act (1974) and was also ordered to pay costs of £12,079, added the independent nuclear safety regulator.
Dr Mina Golshan, ONR’s deputy chief inspector, said: “I welcome today’s guilty plea which recognises the failings by Sellafield Ltd on this occasion that led to an employee sustaining serious injuries.
“This was an entirely avoidable event that occurred due to inadequate training and a lack of supervision.
“As an independent regulator, we will not hesitate to take enforcement action if we consider it is necessary to do so.
“While we are satisfied that Sellafield Ltd is meeting the standards of safety we expect with regards to nuclear safety, we want to see these same standards in place with regards to electrical safety where further sustained improvements are required.
“My team of inspectors will have close oversight of Sellafield’s response to this incident to ensure the root causes are addressed.”
In April 2009, Sellafield Ltd was fined £380,000 after a production worker was contaminated with plutonium.
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