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Nuclear Submarines

My hon. Friend asks a good question. I emphasise again that there are no safety implications from this type of event—a submarine could continue to operate safely. This is a tiny amount of radiation in a coolant that is itself circulating in a closed system inside the sealed reactor shield, so there is no risk to the submarine crew. If such an event occurred, it would be detected almost immediately because of the daily sampling and analysis of coolant water. We are already looking at the operational implications, in a reactor of this type, of a very minor breach. As I have already told the House, the test reactor at Dounreay was restarted in 2012 and has subsequently run without any further problems. It is not absolutely clear that the result of such a minor event occurring in an operational reactor would necessarily mean that the reactor would have to be withdrawn from service. Clearly, we would do so on a precautionary basis while we considered a longer term course of action, but it is not yet clear that that would have to be the long-term state of affairs.