Noel Tierney - a former senior football All-Ireland champion from Co. Galway - has been working on his family farm for nearly sixty years. He went into farming full-time after leaving the county team in 1967.
Noel's son Fergal joined him on the farm after he finished college. One September, the conscientious farmers decided to clean out and disinfect all their slatted sheds. The tank was mostly empty with only about two foot of manure in it.
Noel realised that it had to be agitated before being emptied. Upon discovering a calf left in the shed, they decided to move the animal to a different shed first.
As Fergal stood in the open doorway to guide the calf into the next pen, tragedy struck.
A noxious gas - Hydrogen Sulphide - was released from the agitating slurry. "I always had the feeling that if you were going to be gassed, that you would feel yourself getting weak, but I felt totally nothing," said Noel.
It was later when Noel woke up beside his wife, who then had to deliver the heartbreaking news that Fergal had not survived.
Over the coming days, as Noel's memory of the incident began to return, he realised that Fergal had perished trying to save his father as Noel had been the first to collapse.
Fergal then collapsed just three metres from his father. Noel says that his neighbour Michael, the man who found the pair was very lucky, as the fatal gas must have dispersed by the time he arrived.
"Michael didn't even think for one minute that his life was in danger, coming to rescue us," said Noel, as he explained that his son likewise hadn't realised the danger as he moved to rescue his father.
Noel says that it is frightening to think that the incident happened in such a short space of time.
The question of how it happened on that particular day instead of all the other times, has also occupied Noel's thoughts.
"I always come back to the stillness of the day," says Noel. He said that the same problem would occur with an outdoor tank as there was simply no air movement.
Noel asserts that if he were alive today, there is no way that his son would put an agitator into a tank without contacting the Met Office first for weather conditions.
"With that information available to people. Noel said that it is "very foolish" for people not to check or plan ahead when deciding to spread slurry.
He reiterates the importance of knowing the air movement on the day of slurry agitation.
Fergal Tierney passed away on September 29th, 1993; he was just twenty-three-years-old.