A mechanical fitter, from Scunthorpe, had been operating the 21-ton crane with a colleague and needed it to change direction.

Both men were using the steel pole provided to pull down on a chain which operated the steering mechanism.

As they did, the counter-balance weight and chain detached from the crane and came crashing down.

At the same time, the 19 year-old worker lost his balance and kicked into his colleague, forcing him out of the way. The weight landed on his right foot fracturing it despite his reinforced safety boots.

Drax Power Ltd which employs 750 workers at the nearby power station and Konecranes UK Ltd, a permanent on-site contractor responsible for maintaining all the cranes and hoists, were prosecuted by the Health and Safety Executive (HSE) following an investigation into the incident on 22 March last year.

Selby Magistrates’ Court heard that specialist HSE engineers found that the 13kg weight was not suitably secured in place and was attached with only a single nut or bolt.

They also discovered the crane involved had missed two of its four-monthly services, meaning it was nine months since it was last fully checked.

All six cranes in the mill bay area of the plant were taken out of use after the incident. Three of them were also behind schedule for servicing and numerous defects were found by independent assessors.

HSE Inspector Andy Denison said: “It is not acceptable to turn a blind eye to the on-going maintenance and repair of work equipment.

“The injured worker is, in a sense, fortunate to have suffered only a broken foot. A13kg weight falling from height could have resulted in a much more serious, or even fatal, injury.

“Drax Power and Konecranes didn’t ensure the crane was kept in good working order and this led to the failure of the connection between the counter-balance weight and the steering mechanism of the crane.

“Konecranes had fallen behind on servicing and failed to catch up. Their engineers also gave priority to breakdowns over maintenance.

“Drax continued to allow the cranes to be used even after they found out they had not been serviced. Companies cannot simply contract out their responsibilities and then let the contractor get on with it without checking the work is being done.”

Drax Power Ltd and Konecranes UK Ltd admitted safety breaches and each was fined £13,300 and ordered to pay costs of £3,151.