Ken Palmer remembers standing on the upper deck of HMAS Murchison in 1952. Dressed with his fellow national serviceman in "shorts and sandals," he remembers the mushroom cloud, formed from the explosion of Britain's first atomic bomb at the Monte Bello archipelago, off Western Australia.
"They said, don't face the blast and when I tell you, you can turn around. We had just left our mother's breast, we didn't think much about it," said Mr Palmer, now in his 80s. 
"When we got to Monte Bello it was a complete surprise to us. Nobody ever told us we were there ... circling [to keep] everybody else out of the road until the climate was right to explode this atomic bomb in the bowels of the HMS Plym."
Mr Palmer is one of 23 surviving national serviceman of the 62 who were conscripted to serve on the Murchison in   October 1952.
This Anzac Day Mr Palmer is hoping to reignite a long-running campaign of the surviving servicemen, seeking recognition as "Australian Participants" in the British government's nuclear tests at the Monte Bello archipelago.
The campaign was launched about eight years ago by the late Michael Rowe, who also served on the Murchison. He believed many of the cancers and illnesses suffered by his shipmates were related to nuclear radiation, following their time on the Murchison.
Mr Rowe began the campaign after a 2006 decision to award healthcare assistance to participants in Britain's atomic bomb tests, with the exclusion of all serviceman on the Murchison, on grounds they were not close enough to the blast site.
A Department of Veterans' Affairs spokesperson said Defence Force members who served on the Murchison could claim compensation and benefits under the Safety, Rehabilitation and Compensation Act for any condition, however any claim based on radiation exposure "would not be accepted".
He said the positions of all navy ships that served in the Monte Bello Islands during the British nuclear tests had been "exhaustively" researched.
"The Murchison was located 70 nautical miles south-south-west of the Monte Bello Islands, which was outside the test area. The Monte Bello test area is defined in legislation as the area within 10km of Main Beach on Trimouille Island."
However, as published by Fairfax Media in 2008, photographs of the bomb blast cloud, taken by the men, challenge the distance recorded in official documents.
"If we were able to take that photograph, that would give you an idea of our distance," said Mr Palmer, who has successfully tackled thyroid cancer over the past 30 years. Doctors have not made links on the record, between his cancer and his time in the navy.
Ian Tuckwell, a fellow serviceman, said his health had been good over the years, but he would like to see their participation acknowledged.
"I reckon we were 12 miles away, otherwise a box brownie [camera] could not have taken the photo. I think we deserve something, we were conscripted, we had no choices," he said.
Another national serviceman, Col Crawford, said "there was no denying we were there," adding that he had given up the fight long ago, as it had become "complete and utter bureaucratic nonsense".
Sandy Godfrey, who has assisted Mr Palmer and the campaign over the years, said the 10 kilometre radius was arbitrary, and excludes an enormous number of people who participated.
"From our point of view it appears the government are waiting for them to die, so the issue will disappear."