UK Power Networks (Operations) Ltd has been ordered to pay £420,000 in fines and costs after an employee was killed at an electrical substation in Essex in 2008.
The worker, John Higgins, was 59 years old. He was killed at the Bishops Hall Lane station in Chelmsford in May 2008, when a transformer tap charger he was working on exploded.
Chelmsford Crown Court heard today that a fire was caused at the substation, and Mr Higgins died at the scene despite the arrival of Essex Fire and Rescue within minutes of the alarm being raised by staff from Anglia Ruskin University.
A large part of Chelmsford, including Broomfield Hospital, was blacked out as a result.
A Health and Safety Executive investigation found the firm had failed to properly assess the work, to devise procedures and to train employees.
UK Power Networks has since revised its procedures to safeguard staff.
The Southwark-based firm was fined £275,000 with £145,000 in prosecution costs after pleading guilty to breaching the Health and Safety at Work Act.
HSE Inspector Steven Gill said: “John Higgins lost his life in tragic circumstances that could have been avoided had this activity had been properly assessed and managed by UK Power Networks.
“His death illustrates how dangerous work on or near electrical distribution networks can be, and how imperative it is that employers – large or small - ensure that all activities involving high voltage electrical equipment are properly assessed and that safe systems of work in place.
“There is no room for error or complacency when working with high voltage equipment.”
The HSE offers advice on electrical safety at work on its website.