HMS Tireless "Explosion" Details?

Reading the stories in the British press about the tragedy onboard the HMS Tireless in the Arctic this week, I've reached the conclusion that the Brit journalists are at least as sensationalistic as, if not moreso than, their American counterparts. Still, this article in The Herald seems to have some technical explanations for what happened that actually pass the initial "smell test". Excerpts:
Naval sources said yesterday the investigation team's initial findings pointed to a rapid build-up of pressure in the square-shaped Scog canister, which is designed to burn chlorate at high temperatures to produce lifesaving oxygen.
The sailors had set off one of the candles in the boat's forward escape compartment. The canister containing it blew up a few minutes later.
A naval source said: "These things are ignited by striking a primer and burn extremely hotly, giving off enough oxygen through vents in the canister to supply breathable air. A kilo of the chlorate releases enough oxygen to keep a man alive for six or seven hours.
"The chlorate candle is seeded with iron powder to bring the burn temperature to about 600C inside the container. It looks like the vents may have been blocked. It would go off like a grenade in that confined space."
The story mentions earlier that "SCOG" stands for "Self-Contained Oxygen Generator". After this fairly good start, though, it appears that the author of the article didn't quite understand his notes in one case:
The Scog system is used on exercises to produce oxygen when the attack boats are "running silent" to avoid detection by surface warships' sonar. The usual electrical air-conditioning system potentially produces enough noise to give away the submarine's position.
[Emphasis mine] It's a minor quibble with an otherwise good article (unless, of course, the A/C system aboard Trafalgar-class submarines also includes the "electrolyser" that seems to be the Brit equivalent of an Oxygen Generator.)