Neil Knox, then 69, of Pencaitland, East Lothian, is confined to a wheelchair after suffering irreparable damage to his spinal cord in the incident on 14 March 2013 as he replaced plastic rooflights on a farm shed in Lauder, in the Scottish Borders.

Jedburgh Sheriff Court heard that Knox, a time served and experienced worker without any formal training in roofwork, was employed by David Miller Contracts Ltd to carry out roof repairs at the farm.

Knox had climbed onto the roof using a ladder and crawlerboards to allow him to access the rooflights. He removed three of them before being called down for a tea break.

Knox has no recollection of the incident that followed. A colleague knew he had gone back up onto the roof as he heard him moving about before hearing a loud noise.

He found Knox lying on the floor underneath a fourth rooflight which had a large hole in it.

Knox was airlifted to hospital with broken ribs, a broken sternum and punctured lungs. His spine was fractured in two places, damaging his spinal cord, which has left him confined to a wheelchair with no movement or sensation in his legs.

He also only has 50% lung efficiency due to partial paralysis of his chest muscles.

An HSE investigation found that David Miller Contracts had identified that the roof surface was likely to be fragile but failed to carry out a site-specific risk assessment and subsequently failed to plan the work properly.

The company also failed to identify that the work to replace the rooflights could be done from a working platform beneath the roof, or by using safety nets or harnesses to keep workers safe.

There were no measures in place to prevent someone standing on the fragile roof or rooflights other than the crawlerboards, which did not have any handrails to prevent workers stepping off them.

David Miller Contracts Ltd, of Gifford, East Lothian, was fined £50,000 after pleading guilty to breaching safety regulations.

Following the case, HSE inspector Ritchie McCrae said: “This was an entirely avoidable incident. Falling from height is one of the most common reasons for injuries and even fatalities at work.

“David Miller Contracts Ltd should have been aware of the risks and the precautions that needed to be taken before starting the work.

“The dangers of fragile roofs are well known and consideration should have been given to using a platform underneath the rooflights or installing safety nets.

“The system of work planned by the company was unsafe, resulting in terrible life-changing injuries which have had a profound effect on Mr Knox and his family.”