It was not his first offence.
Another man, and the firm he ran, were also prosecuted and fined for their part in the incident.
The victim, 53-year-old Ken Joyce from Lanchester, County Durham, was working for Allan Turnbull, trading as A&H Site Line Boring & Machining, when the incident happened on 2 December 2008.
Mr Joyce was dismantling the structural steelwork of the roof of the burning hall at the Swan Hunter shipyard in Wallsend, Newcastle.
During a four-week trial at Newcastle Crown Court, a jury heard how Mr Joyce was working from one platform while two colleagues were working from another. They were dismantling the structure and using a crane to lower the steel beams to the ground.
While removing a beam brace connecting two plate girders, one of the plate girders struck Mr Joyce’s basket, knocking the machine over. Mr Joyce fell to the ground, suffered serious head injuries and was pronounced dead soon after.
A joint investigation carried out by Northumbria Police and the Health & Safety Executive (HSE) established that North Eastern Maritime Offshore Cluster Ltd (NEMOC) had subcontracted the dismantling work to Allan Turnbull.
The jury was told that NEMOC and its director Christopher William Taylor failed to check that Mr Turnbull had the necessary competence to carry out the work.
The police and HSE investigation also found that Allan Turnbull had failed to adequately plan the work.
Allan Turnbull, 61, of Boundary Cottages Farm, Inkerman, Tow Law, County Durham, was found guilty of gross negligence manslaughter following the trial. He had earlier pleaded guilty to breaching Sections 2(1) and 3(1) by virtue of Section 37 of the Health and Safety at Work etc Act 1974. He was sentenced to three years in prison.
Allan Turnbull had previously been prosecuted in November 2005 after an employee sustained serious leg injuries while dismantling a redundant brick manufacturing plant.
North Eastern Maritime Offshore Cluster Ltd (NEMOC), which had been operating from the Swan Hunter Yard, was fined £1 for each offence after it was found guilty in absence of breaching Sections 2(1) and 3(1) of the Health and Safety at Work etc Act 1974. The company is now in liquidation.
Christopher William Taylor, 51, of North Cottage, Adderstone Crescent, Newcastle, was fined a total of £30,000 (£15,000 for each offence) and ordered to pay £50,000 costs.
HSE inspector Emma Scott said afterwards: "This was a tragedy that could easily have been prevented had a safe system of work been in place.
"Instead Ken Joyce lost his life as a result of collective failures which included not preparing in advance a detailed plan of how the work should be carried out and no lifting plans to ensure the safe removal of the beams.
"I hope other companies can learn from this and ensure they take the necessary action to deal with the high risk involved with work of this nature."