Byline: Alun Thorne
On May 6, 1953 Leading Aircraftman Ronald Maddison, aged 20, from Consett, Co Durham, was one of a team of six servicemen who entered a chamber at Porton Down wearing respirators.
All were exposed to 200 milligrammes of Sarin which was dropped on to a piece of uniform material loosely wrapped around their arms.
LAC Maddison and a colleague sat in the chamber in their masks playing noughts and crosses while they were under observation.
After 23 minutes however, he said he felt 'pretty queer' and was taken outside where he began to experience breathing difficulties and was sweating.
He was given an antidote but his condition worsened and he said he could not hear.
Also in the group being tested was Michael Cox, who said he saw Mr Maddison slump forward in his chair after he was exposed to drops of Sarin.
The pair had volunteered to take part in the trials after seeing notices posted at their RAF bases and being tempted by the payment of 15 shillings and assurances they would come to no harm, the hearing was told.
LAC Maddison was taken by ambulance to the medical centre and given further treatment but lost consciousness.
Attempts to revive him, including being given oxygen and an adrenaline injection into his heart, all failed.
Military documents claimed that after visiting the base following his son's death, John Maddison agreed to protect national security by simply telling the family his son had died from 'an unfortunate accident while on duty'.
But a letter written to the military chiefs from Mr Maddison showed he rejected an offer of pounds 3 towards funeral expenses, saying: 'I would like to know a bit more about my son's death as I am not satisfied with what I have been told.' Wiltshire Coroner David Masters told the hearing efforts were made to shroud the original inquest in secrecy. The secrecy has continued to this day.
Mr Masters said he had to negotiate with The Pentagon to have documents released although some were read by the jury behind closed doors.
Porton Down, which now employs 3,000 people, has been at the frontline of Britain's research into how we make use of and defend ourselves against chemical weapons for the last 85 years and much of the work at the centre remains top secret.
Porton Down was set up in March 1916 as an 'experimental ground' in response to Germany's use of chemical warfare in the First World War. …