Russian Sub Accident Kills 20; Circumstances Unclear

Apparently, there was some kind of problem on board a new Russian nuclear submarine that was undergoing the first phases of its sea trials. Reports indicate that the submarine apparently had a malfunction/accidental release involving its fire suppression systems.

That's where things get hazy.

A new Russian submarine's fire safety system malfunctioned as the nuclear-powered vessel took a test run in the Sea of Japan, suffocating 20 people and sending 21 others to the hospital, officials said Sunday.

It was Russia's worst naval accident since torpedo explosions sank another nuclear-powered submarine, the Kursk, in the Barents Sea in 2000, killing all 118 seamen aboard.

The victims suffocated Saturday after the submarine's fire-extinguishing system accidentally turned on and released Freon gas, said Sergei Markin, an official with Russia's top investigative agency. He said forensic tests found Freon in the victims' lungs.

The submarine itself was not damaged and traveled back to its base on Russia's Pacific coast under its own power Sunday, Russian navy spokesman Capt. Igor Dygalo said.

The nuclear reactor that powers the sub was operating normally and radiation levels in the sub were also normal, Dygalo said. He said the accident affected two sections of the submarine closest to the bow.

Seventeen civilians and three seamen died in the accident and 21 others were hospitalized after being evacuated to a destroyer that brought them to shore, Markin said in a statement, revising earlier casualty figures.

One has to wonder why those in the forward compartments did not don their safety masks and equipment. The problem was confined to the forward two compartments, and that suggests that either the forward compartments were previously sealed when the incident occurred, or there was sufficient time to seal them before the chemical spread throughout the boat. If it's the latter, one has to question why those in the forward compartments did not have sufficient time to get out. Were sufficient safety measures in place?

Bubblehead, who is one of my go to sources for all things submarine related, notes that this particular submarine is the Russian boat the Akula-II submarine RFS Nerpa, which is scheduled to be transitioned to the Indian Navy.

The fire suppression system was apparently accidentally turned on, which suggests that the Russians are looking to scapegoat someone on board, rather than some kind of manufacturing or design defect. It's also curious why the investigators would claim that freon was found in the lungs of the victims, and not halon, which is the primary fire suppression system used. Both chemicals are part of the same chemical family, but each has specific uses.

I expect that the nature of the accident will evolve as more information leaks out.