Motorcyclists are 11 times more likely to be killed as a result of fuel spill than all other road users, but no-one is safe, writes Graeme Smith.
The family photographs around the lounge of Robert and Annette Duncan's home instantly reveal their pride in their children and grandchildren.
However, while the photographs of their son Roderick and his family are recent, the pictures of son Andrew are ageing. The climbing boots in the black-and-white photograph which has pride of place are old-fashioned, his father points out, because it is almost nine years since it was taken.
On a bright May evening, Andrew went out for his first motorcycle ride of the summer and, in an instant, and because of someone's stupidity, his life was needlessly ended.
His killer was invisible - it was not a driver speeding, cutting a corner or even losing concentration. It was a patch of diesel on the road surface caused by someone being too careless or lazy to ensure there was no spillage from their vehicle's fuel tank.
He and a motorcycling friend had just travelled a few miles with Andrew, 32, following behind when they reached a corner on the A944 Alford road west of Dunecht near the entrance to Craigenlow Quarry in Aberdeenshire.
Andrew's friend was first through the corner and, although his bike wavered when he hit the diesel, he remained upright.
When Andrew failed to follow him he turned back and discovered the tragic scene. Andrew had lost control of the bike in the same way as if he had hit black ice. He had been thrown into a rocky field several feet below the road.
He suffered brain and neck injuries. His parents were later forced to make the decision to turn off his life support machine - although not until his organs had been donated to save the lives of four other people.
For his parents the pain has never faded and they recoil in horror when they see a speeding motorbike, fearing the rider could become another diesel victim.
"Andrew's death was unnecessary, a waste of a good life," said Mr Duncan.
"He did nothing wrong. He had been a motorcyclist for quite a few years, but he always put his machine away for the winter and had just taken it out and had it fully serviced, and this was his first day on the road.
"The day after the accident two police officers said they had followed the trail of diesel from the accident site several miles up the road and every time they came to a bend there was another diesel spill so either the vehicle didn't have a diesel cap on or had a very badly fitted one.
"Eventually the trail petered out and the person responsible was never found.
"Andrew was an electronics engineer, very precise in the way he worked and the way he lived.
"We found everything filed away after we had to switch off the life support machine. All his papers were neatly filed.
"He was the sort of chap who didn't take chances. When he got the bike he went down to Edinburgh and did a week-long advanced course before he started.
"He knew exactly what he was doing. He was a mountaineer, he did white water canoeing.
"He was adventurous but he never took risks."
Mr Duncan was speaking a week after the deaths of a woman and her two daughters on the A92 in Aberdeenshire.
The focus of the investigation into the death of Ann Copeland, 45, and her daughters Niamh, 10, and Ciara, seven, is on a possible spillage.
Mr Duncan is keen to encourage more campaigns to educate the public about the dangers of diesel spillages.
Although motorcyclists are 11 times more likely to be killed as a result of a spill than a car driver, all road users, including pedestrians, are at risk.
High-profile victims of spillages include Ewan McGregor, who narrowly escaped injury when his bike hit oil near Inverness, and the late Frances Shand Kydd, Princess Diana's mother, whose car overturned after skidding on a diesel spill near Oban.
One of the biggest campaigns is Killspills, which is sponsored by the British Motorcyclists Federation (BMF) and which is supported by, among others, the RAC Foundation.
Jeff Stone of the BMF said their aim was to achieve greater public awareness and also for there to be more prosecutions.
He said they were having success with major companies such as Sainsbury's and Asda fitting anti-syphon devices to their entire fleets which also prevented spillage.
"The general rule is that the scruffier the vehicle the less likely it is to be properly maintained and the more likely there will be spillages.
"The biggest problems are: tanks being overfilled, (which is known as necking it in the trade), leaving insufficient room for the expansion of the fuel in hot weather; the filler cap not being refitted properly; or the filler cap not having a proper seal.
"The main culprits are lorries and vans which have their fuel tanks low down. The diesel swills about the tank and, as the vehicles corner, it is forced up the pipe and if there is not a proper seal or cap it dribbles out on to the road."
He explained that while petrol evaporates diesel remains on the road and not only causes a danger at the point it spills but can contaminate the tyres of a passing vehicle creating a danger and the next hazard.
"With diesel at about £1 a litre you don't want to splash it about and it is cost effective to fit devices to stop fuel being stolen or spilling out.
"We would like to see more prosecutions. It is careless or dangerous driving.
"The act may be inadvertent but it is through someone not taking their job seriously that spillages occur because if vehicles are properly maintained, as the manufacturers intended, the diesel will not spill out.
"Diesel spills kill people, they wreck lives, waste scarce resources, pollute the environment and cause damage to the road surface."
Real cost of diesel
- 22 - The number of people killed by diesel spillages between 2000 and 2005.
- 595 - The number of serious accidents on the roads between 2000 and 2005.
- 617 - The number of people who were killed or seriously injured between 2000 and 2005.
- 3020 - The number of accidents resulting in slight injury between 2000 and 2005.
- £33.5m - The cost of oil/diesel related accidents in 2005.












