Christopher Kaye, 57, suffered life-threatening head injuries when he was hit in the face by a steel locking bar at a construction site in Sheffield in October 2008.

His employer Euro Dismantling Services has agreed to pay a lump sum of £1.75m, plus annual payments of £135,000 for life.

Kaye’s legal team said the damages package was likely to reach £4.2m based on a life expectancy of 20 years.

Approving the settlement, Justice Popplewell told London’s High Court that Kaye had shown ‘outstanding courage’ since his life was turned upside down.

Kaye was working on a construction site in Attercliffe, Sheffield three years ago. Tragedy struck shortly after 9am when he was asked by a supervisor to remove a grapple attachment from an excavator.

He was changing the attachment when the connecting metal bar fixing the grapple to the boom sprang out, hitting him in the face causing devastating injuries to his head and brain.

Kaye was taken to Sheffield Hospital where he underwent life-saving surgery but was left with severe brain damage.

Lawyers argued that Kaye had received inadequate training and that equipment that could have allowed him to carry out the job more safely was only bought after the accident.

Euro Dismantling Services initially denied any responsibility but eventually accepted 90% liability, his lawyers said.

Jill Greenfield from law firm Field Fisher Waterhouse, said: “This was a terrible accident that could have been avoided had better equipment and training been in place at  Kaye’s workplace.

“This accident has had a profound effect on Kaye and his family who are devoted to him. ”

“The money will allow Chris to have round-the-clock care and support in what are very difficult circumstances.”

Kaye’s wife, Sue, said: “No amount of money will help Chris to fully recover or give me back my loving husband of 32 years, nor will my children ever have the same dad.”