Christopher Carson, who was 23 at the time, competed as a floor gymnast at national level and was also a coach in the sport.

As his day job, he was working as an electrician’s labourer for Robert A.S. Crockett and Partners Ltd.

Crockett and Partners had been contracted by Electroguard Security Systems to fit a lighting system as part of a larger project at Dundee Cold Stores Ltd, Kingsway West, Dundee.

Dundee Sheriff’s Court heard that on October 3 2008, Carson was attaching cables to the wall of the building in order to install the new security system.

One of the cables he needed was on the roof of the building so he decided to use a mobile platform to get to the roof level and then walk across the roof to retrieve it.

Once on the roof he realised he needed some clips, and as he was returning to the platform he stood on a roof light and fell through it, hitting machinery in the building below, before landing on the concrete floor.

He suffered a number of fractures to his back as well as fractures and dislocation to his left shoulder.

He also suffered a puncture wound to his lower back from a drill bit which was in his pocket when he fell.

Carson required surgery to reattach three tendons to his shoulder and had to undergo physiotherapy. He still suffers from chronic pain in his back and shoulder from which he is making a slow recovery.

An HSE investigation found that Dundee Cold Stores had not asked either Electroguard Security Systems or Robert A.S. Crockett and Partners Ltd for a written risk assessment for the work they had been asked to carry out.

Nor was there a method statement from either company as to how the work was to be carried out safely.

Robert A.S. Crockett and Partners Ltd of Scott Street, Dundee was fined £66,000 after pleading guilty to safety breaches.

Electroguard Security Systems of Strathmore Avenue, Dundee was fined £135,000, and Dundee Cold Stores of Whittle Place, Gourdie industrial Estate, Dundee fined £135,000 after they both pleaded guilty to safety breaches.

After sentencing, HSE Inspector Harry Bottesch said:”Mr Carson has suffered significant and lasting injuries because his employer left him to work at height unsupervised and without clear instructions about what work he was expected to do and how he was to do it.”