The 64-year-old man, who does not wish to be named, was airlifted to Southampton hospital after being crushed by the toppling steel beam on June 10 2011.

He suffered numerous injuries including a fractured skull, two crushed discs in his back, a broken knee and ankle bones, as well as a blood clot on his lung.

Portsmouth magistrates heard the victim was working on a steel beam that was sitting unsecured on a metal trolley.

He was manoeuvring an overhead crane when the hook of the crane struck the beam and sent it toppling from the trolley.

He remained in hospital for a month and is still having to undergo surgery and treatment two years later.

An HSE investigation found the company had not carried out a proper assessment of the risks involved in that particular work process, and so had failed to put in simple safety measures that would have prevented beams from being knocked and becoming dangerously unstable.

Condor Allslade was fined £16,000 and ordered to pay £5,074 in costs.

After the sentencing, HSE Inspector Craig Varian said: “The painful and debilitating consequences of these dreadful injuries will be with this man for the rest of his life.

“The term ‘risk assessment’ is often lambasted as a technicality or part of a tick-box exercise. However, the true meaning of the term and its importance are very starkly demonstrated in this case.

“Had Condor Allslade undertaken a risk assessment and then taken the action necessary to mitigate the risks, the incident could have been avoided.

“In this case, inexpensive and easy-to-implement solutions were available and the company did put measures in place after the incident. Sadly that was too late to prevent an individual needlessly suffering multiple injuries.”