No, there is no regulation. Actually, there is no regulation that forces the railway to purchase that type of equipment. However, what we provide within the track safety rules is that if you do use that type of equipment, you can reduce the number of visual inspections, because these vehicles do a better job. But if you don't have those vehicles, you have to increase your number of visual inspections.
On December 11th, 2007. See this statement in context.