THE tragic deaths of a father and two sons who were overcome by toxic fumes have made every farmer acutely aware of the dangers of slurry tanks, a coroner has said.
Rising Ulster rugby star Nevin Spence, his brother Graham and father Noel died following the accident at their farm near Hillsborough last September.
Yesterday an inquest found that the three had died from drowning and the effects of inhaling slurry after going to the aid of a family dog.
Senior coroner John Leckey said it was an "unbelievable tragedy" and the worst farming accident in Northern Ireland for 20 years.
He said the case served as a warning to the whole farming community.
Malcolm Downey, an inspector with the Health and Safety Executive (HSE) in the North, said farmers were now very aware of the dangers.
"This terrible tragedy has brought the whole issue very closely to the front of the mind of every farmer," he said. The second day of the inquest in Belfast heard the men died after being overcome by slurry fumes containing chemicals including methane, ammonia, carbon dioxide and hydrogen sulphide.
Jim King, principal inspector with the HSE, said that the chemicals displace oxygen and can create a lethal environment within moments of exposure.
Mr Leckey pointed out that hydrogen sulphide has the same lethal effects as hydrogen cyanide.
"There isn't anyone in the country who is unaware what a dangerous substance cyanide is, and we are talking about the same thing," the coroner said.
The tragedy was triggered when a collie dog fell into the tank, which was situated below a cattle shed and contained less than four feet of slurry.
The inquest heard the animal may also have been overcome by the fumes.
Graham Spence (30) went to the pet's aid but, as he exited the tank, he was overcome and slumped back into the pit.
Nevin (22) went to his brother's aid but was also overcome by fumes.
Their father, Noel, followed them into the pit and managed to find Graham.
But as he carried his son back up the ladder, the 58-year-old also succumbed to the gases.
His daughter Emma – Nevin and Graham's sister – twice tried to rescue the men.
She was also overcome but survived.
Mr King said it was a natural instinct that someone would try and help other members of their family, despite the risks.
He stressed that any shed containing a slurry tank should be well ventilated, but said there were no building regulations that required this.