To ask the Secretary of State for Defence what assessment he has made of the potential (a) risk and (b) effects of a fire on a British submarine which lasts for 24 hours.
The risks associated with fires on submarines are taken extremely seriously by the Ministry of Defence, including consideration of their potential effects. All Royal Navy submarines are required to hold a Certificate of Safety—Fire, which is issued by the Naval Authority when it has been demonstrated that fire risks have been reduced so far as is reasonably practicable. There is also an obligation to seek continual improvement both for in-service submarines and for new classes of submarine.
Risks are reduced through a range of measures. This includes designing the submarine to prevent fires where possible by, for example, using non-flammable materials. In addition, fire-detection systems and both automatic and manual fire-fighting systems are fitted, which are intended to detect and extinguish fires as quickly as possible. Finally, all submariners complete rigorous fire training, followed by regular practice exercises, to enable them to act appropriately and effectively in an emergency situation.
For submarines that are undergoing maintenance, further precautions are taken that supplement operational procedures and systems, or alternative arrangements are introduced when deeper maintenance is being carried out. This includes liaison with local fire and rescue services regarding the provision of external fire-fighting capability.
As a result of the comprehensive procedures and systems that are in place, the likelihood of a submarine fire lasting for 24 hours is considered to be extremely remote.