A teenage worker fell to his death while carrying out repairs to lights on a barn roof, a court heard.
Jamie Lee Duddin, 18, plunged 30ft through a roof panel made of fibre cement board, landing on a concrete floor.
He was working with another Scotts of Whittington employee to complete the repair at Heddon Low Farm, Heddon on the Wall, Northumberland, when the accident happened on 23 July 2010.
Newcastle Crown Court heard that Mr Duddin, of Corbridge, Northumberland, was rushed to hospital, but died two days later.
A joint investigation by Northumbria Police and the Health and Safety Executive (HSE) found that the work had not been properly planned.
It also found that inadequate equipment had been provided and that the workers were not properly trained or supervised.
The company involved, Scotts of Whittington Ltd, was fined £65,000 and ordered to pay £19,000 costs.
Company director Alfred Wood, 65, and his son Christopher Wood, 41, also a director, admitted breaching health and safety laws and were fined £13,000 and £2,000 respectively.
Speaking after the hearing, an HSE inspector warned that falls through fragile roofs, often at agricultural premises, were a common cause of workplace deaths.
“This was a tragedy that could and should have been avoided,” said HSE inspector Martin Smith.
“Instead a young man has lost his life as a result of collective failures, including confusing instructions on how the work should be safely carried out, a lack of supervision and a failure to properly plan the work and provide adequate equipment.
“Falls through fragile roofs, often at agricultural premises, are a common cause of fatalities in the workplace. Maintenance to industrial roofs should ideally be carried out from below using a safe working platform. If access on to a fragile roof surface is unavoidable, then adequate working platforms should be provided on the roof slope with safety nets installed beneath.
“As this case shows, being aware of the risk is not enough to prevent it from happening.”
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