HC Deb 29 July 1964 vol 699 c313W
54. Sir B. Janner

asked the Minister of Transport whether, in view of the increasing use of differential speed limits on roads, he will take steps to ensure the greater accuracy of speedometers in all motor vehicles using the roads.

Mr. Marples

No. The Regulations require speedometers to be accurate within a margin of 10 per cent., whenever the vehicle to which they are fitted is exceeding 10 m.p.h.