Are cars stopped on the hard shoulder of a motorway at immediate risk?

A friend recently attended a Speed Awareness Course and said that they had been told the average time stopped on a motorway hard shoulder before being hit from behind is 25 minutes. Is this correct? If so, it needs wide publicity.

Asked on 5 May 2012 by CH, Guildford

Answered by Honest John
Yes, and it's another strong argument for runflat tyres. This is the reason why the police get stranded cars towed off the hard shoulder as quickly as possible, regardless of what rescue service the driver may be with.
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