Russian Submarine K-152 Nerpa - 2008 Accident

2008 Accident

An accident aboard K-152 Nerpa occurred at 8:30 PM local time on 8 November 2008, during an underwater test run in the Pacific Ocean. A total of 208 people - 81 military personnel and 127 civilians - were on board at the time of the accident. At least 20 people were killed by asphyxiation and at least 21 more were injured, marking the worst Russian submarine disaster since the Kursk sank in 2000. Three of the dead were military personnel and the rest were civilians from the Vostok, Zvezda, Era and Amur shipbuilding yards who were members of the acceptance team.

The incident involved the accidental triggering of a fire extinguishing system which sealed two forward compartments and released freon R-114B2 (Dibromotetrafluoroethane) gas into them. According to survivors, those affected by the gas release were caught off guard and may not have been alerted in time due to warning sirens sounding only after the gas had already begun pouring in. Some of the victims were reported to have been unable to don breathing kits before they suffocated.

On 10 November, a Russian Navy statement blamed the disaster on an "unsanctioned operation" of the fire suppression system aboard the Nerpa. Preliminary investigations concluded that the system had triggered automatically without human intervention. On 13 November, naval investigators announced that a crewman had turned on the system "without permission or any particular grounds".