A "highly dangerous" man was locked up indefinitely today for what a judge described as a "horrific" offence of attempted arson.
Thomas Garrington, 27, of Church Road, Seven Sisters, south Wales, was told that he must serve a minimum of 5 years - less 335 days already spent in custody - before he can be considered for release by the parole board.
His sentence was handed down by Mr Justice Owen, sitting at London's Royal Courts of Justice, following Garrington's earlier conviction at Swansea Crown Court for attempted arson with intent to endanger life.
Imposing an indeterminate prison sentence for public protection, the judge said Garrington had gone from his home in Seven Sisters to a house in Cory Street, Resolven, having equipped himself with a can of petrol.
After bursting into the living room of the house - occupied at the time by a woman and three children - he started distributing petrol around.
A jury, which cleared him of attempted murder, heard how the house erupted into flames during the incident one night last October.
After helping two children escape, the woman raced upstairs to rescue a third - none of the occupants can be named for legal reasons.
Mr Justice Owen told the defendant that he accepted he did not set the petrol fumes alight and that it was not established he was carrying the means of ignition, but pointed out that it was inevitable that the fumes would ignite.
He added: "Mercifully, the occupants escaped harm in the ensuing fire."
He told Garrington: "In my judgment you are a highly dangerous man. I do however accept... that you now feel a deep regret and remorse for what you did that night."
But he added that he had no doubt that he posed a "significant risk to members of the public of serious harm".
Earlier, the judge had heard in mitigation that Garrington was suffering from a "psychotic" episode caused by a cocktail of drink and drugs at the time and he was also seriously injured in the blaze.