The self-contained oxygen generator, known as a Scog
, which caused the tragedy is believed to have been from a supply of almost 1,000 found in a Hazardous Waste Store close to the Royal Naval port in Plymouth, the inquest in Sunderland heard.
Mr Winter said: "There was a culture of complacency regarding the risks posed by SCOGs
and a tolerance of practices likely to increase those risks."
The coroner said Christopher Clark, a civil servantwith theMarine Environment Survivability and Habitability Project, decided to bring back into use the Scogs
from the hazardous waste depot because he wanted to cut costs for the MoD.
Mr Winter said: "Mr Clark's decision exemplified and contributed to systemic failures in the assessment and management of Scogs
. Those systemic failures led to the contamination and damage which, in turn, caused the explosion." Immediately after the hearing Alan, 56, said he could not accept an apology and wanted the resignation of those who caused his son's death.
The explosion in a confined compartment was caused by a damaged self contained oxygen generator (Scog
) moments after it was activated by one of the men.
The 20-year-old died after an oxygen device, known as a Scog
, erupted and tore through a cabin of nuclear submarine HMS Tireless in March 2007.
HMS Tireless's commanding officer, Captain Iain Breckenridge, said he did not know exactly where the Scogs
were stored but that he trusted his crew to make sure the ship was in order.
Asked if there was a "significant financial motivation" for getting the Scogs
back into service, Mr Clark replied: "What I saw was an indication we might be wasting money."
He agreed to allow 20 tonnes of Scogs
from the dump to be taken to the Royal Navy stores in Devonport, for use on submarines.
Just 90 of the 294 of these Scogs
, made by Molecular Products Ltd, had been recovered.
Mr Clark visited the dump on June 27 2006 after he was contacted by a Defra official who said there was almost pounds 750,000 of recyclable Scogs
in storage there.
Royal Navy engineer Chris Clark, was responsible for Scogs
throughout the fleet.