Steven McColgan, 37, from Edinburgh, was carrying out concrete post tensioning work on the construction of the adult block of the Royal Victoria Infirmary at the time.

Newcastle Crown Court heard that part of an unsupported working platform broke away when he stood on it, causing him to fall 21 metres to the ground.

McColgan suffered serious multiple injuries to his head and body in the fall and his injuries continue to be life-changing.

The HSE investigation revealed that sections of the falsework, acting as a temporary structure supporting the working platform, were removed before work on the concrete slab was complete.

Both companies, which are based at Bridge Place, Anchor Boulevard, Admiral’s Place, Crossways in Kent, pleaded guilty to breaching Section 3(1) of the Health and Safety at Work etc Act 1974.

Laing O’Rourke Construction Ltd was fined £50,000 and ordered to pay costs of £13,756 and Expanded Structures Ltd was fined £75,000 and ordered to pay costs of £14,154.

After the case, HSE Inspector Victoria Wise said: “Laing O’Rourke Construction Ltd and Expanded Structures Ltd failed in their duty of care to Mr McColgan, who was lucky to survive the fall.

“It is tragic that Mr McColgan’s injuries could so easily have been avoided if those in a position of responsibility had effectively discharged their duties”.

“Laing O’Rourke Construction Ltd had a duty as principal contractor to ensure that safe systems of work were in place and were being implemented on their site.

“The company had received previous advice from HSE on this specific matter, at another Newcastle site only two years earlier.

“Specialist contractor Expanded Structures Ltd had a duty to ensure that the risks associated with their work had been adequately assessed and that day to day controls and systems of work were effective”.