Freon cause of death in Russian sub accident

BBC:

At least 20 people have died in an accident on a Russian nuclear submarine when a fire extinguishing system was activated by mistake.

Russian Pacific Fleet spokesman Igor Dygalo said both sailors and shipyard workers died in the accident, which occurred during sea trials.

The dead were suffocated by freon gas, which is used to put out fires as it removes oxygen from the air.

The vessel was not damaged and there was no radiation leak, Mr Dygalo said.

It is the worst incident for the navy since the sinking of the Kursk submarine in 2000, which left 118 dead.

...

Capt Dygalo said the incident happened after the fire extinguishing system "went off unsanctioned".

...

The BBC's Richard Galpin in Moscow says that in normal cases of a fire on board a submarine, the area would be evacuated and sealed off before pumping in freon gas.

The gas removes oxygen from the air - to put out the fire - but if anyone is still trapped inside that area, they face suffocation.

...

The story does not indicate whether the freon caused to hole in the ozone to expand. That was the environmentalist theory that caused the US to ban the use of freon in air conditioning. I think it has since been called into question but it is interesting that the Russians would use such quantities of freon on their submarines.

The photo of the sub shows a somewhat elegant design crudely built. The nose of the sub does not look as hydrodynamic as you might expect for an advanced submarine. Danger Room shows a different view of the sub. Russian technology still appears to be quite crude in other areas as was seen in the recent war with Georgia. They seem to have some real quality control issues and this accident only confirms they still have a ways to go on that point.

This AFP photo of the Kursk which sank in 2000 feet of water also shows very crude construction. Here is the AFP story on the most recent accident.