A union is calling for tougher laws governing the construction and maintenance of windfarms following the death of a pensioner who was working as a security guard on a site in Ayrshire.

Unite Scotland said the details of what happened to the 74 year old – who has yet to be named – were not yet clear.

However the union was already investigating the dangers of windfarm working, following two previous incidents, an official said.

The man and a colleague were stranded in heavy snow while working at Afton Windfarm, near Craigdarroch Farm, by New Cumnock on Sunday. Police said they had been left without heat or power. Although a Police Scotland mountain rescue team located the men and airlifted the 74 year old to Edinburgh Royal Infirmary, he later died. The condition of his 43 year-old colleague is not yet known.

Stevie Dillon of Unite Scotland said: “How long is it going to be before the Government and HSE take action to prevent these totally avoidable deaths? How many more workers will perish because nothing has been done to establish proper legal safeguards for the construction and maintenance of wind farms?”

He said the HSE were already investigating two other deaths on windfarms and are expected to make recommendations regarding health and safety issues.

Stevie Dillon said: “Our experience shows that some of the conditions which workers on windfarms have to put up with represent a return to the ‘bad old days’ in the construction industry before unionisation. Of course the laws governing wind farms should be a special case. But right now Unite is building the union on wind farm sites to fight for better terms and safer working conditions.”

The site is still under construction and had been expected to begin production early this yeaer. In a statement Afton Wind Farm Ltd said: "We confirm that there has been a fatality in connection with the project. Our deepest sympathy and thoughts are with the family of the deceased at this time.

“Health & Safety is taken very seriously by Management and we are cooperating with the HSE and Police in their investigations. In addition, we have also commenced our own independent investigation into the incident.”

Police and the Health and Safety Executive have investigations underway and a report is expected to be sent to the procurator fiscal.