Had a small container of sterile water been located in St James's Hospital on the morning of January 9th, 1979, Mr John Berry would be alive today.
A sufferer of mild haemophilia A from Athy, Co Kildare, he was admitted to the hospital the previous night with a nose bleed and treated with cryoprecipitate, a locally-made clotting agent. Hospital records, shown for the first time to the tribunal yesterday, recorded that the nose bleed had stopped and that the father of three was "in no distress".
At 6.45 a.m. on the 9th, however, the bleeding started again. A junior doctor on duty planned to administer a further treatment of cryo but there was insufficient sterile water available to prepare the product.
After consultation with a senior doctor, it was decided to administer a commercial factor 8 concentrate instead - a product associated with a higher risk of viral infection.
It was this product which infected Mr Berry with hepatitis C, a condition which contributed to his death six months ago from liver failure.
"Why was it given to me when the blood wasn't right?" Mr Berry asked the tribunal last May while in the latter stages of his illness.
The question was put to Prof Ian Temperley yesterday as the third phase of the tribunal opened - that dealing with the response of treating doctors, State agencies and the Department of Health to the tragedy.
Prof Temperley, medical director of the National Haemophilia Treatment Centre between 1971 and 1995, was not involved in the fatal decision in Mr Berry's case. But he was responsible for formulating a policy on the use of commercial concentrates by treating doctors, including those at his own hospital, St James's.
Such a policy document was adopted in January 1980 by the National Haemophilia Services Co-ordinating Committee, a non-statutory advisory body whose membership included blood bank officials, doctors and members of the Irish Haemophilia Society.
The document expressed a preference for the use of locally-made products. However, recognising the advantages of concentrates in terms of ease of use and effectiveness, it said the following people should be treated with them: "(a) patients with inhibitors; (b) patients requiring supplemental treatment for operations; and (c) patients with severe allergic reactions to cryo."
Prof Temperley admitted yesterday that concentrates were used well beyond these limited circumstances. In fact, they may have been used "preferentially" for operations, as well as in out-of-hours situations.
In a crucial admission, Prof Temperley said no distinction was made between mild and severe haemophilia patients. Nor was there a policy on the treatment of patients not previously exposed to concentrates.
When it was put to him that such a policy should have existed, Prof Temperley replied that the perception here, in the UK and the US was the same at the time. The risk of hepatitis infection was perhaps not taken as seriously as it should have been by both doctors and patients, he said.
It is by no means clear, however, that Prof Temperley's view on this issue was shared by all treating doctors.
In a 1979 report on liver disease in haemophiliacs, Dr Helena Daly - a subordinate of Prof Temperley's at St James's - warned that if home treatment, using commercial concentrate, brought a definite threat of liver disease "then risk may exceed benefit".
She said: "certainly we would no longer recommend that mildly affected patients who only need occasional (treatment) begin on concentrate therapy but he should be given single donor therapy instead".
Had this recommendation been accepted infections such as that to Mr Berry might have been avoided. As a mild haemophiliac, he would have been confined to using single donor, or cryo, therapy instead of concentrate.
Prof Ernest Egan, a Galway-based regional haemophilia treater, made a similar recommendation in 1984, saying the use of imported concentrates should be restricted to "critical clinical situations".
Prof Temperley may find himself more isolated on the issue when Dr Daly and Prof Egan take the stand at later sittings.
They will be among about six treating doctors to be called to the tribunal for this phase, perhaps the most crucial of the inquiry. After all the years of waiting, haemophiliacs and their next-of-kin are finally having the details of the tragedy laid bare.
Sadly, it is too late for Mr Berry, however. He had stated last year that his wish before dying was to find out who was responsible for administering the product which infected him. Like 75 other haemophiliacs, he died without knowing the truth.