asked the Under-Secretary of State for the Home Department what investigations have been carried out by the Road Research Laboratory as to the average speeds at which goods vehicles of an unladen weight of over three tons are travelling on typical stretches of open road in Great Britain at the present time; and whether he can make such information available.
The Road Research Laboratory of the Department of Scientific and Industrial Research, as part of its programme of research on the prevention of accidents, has made some measurements of the average speeds of commercial vehicles on comparatively open roads. This was found to be about 27 m.p.h. although the vehicles were subject to a 20 m.p.h. limit. Well over 90 per cent. of them were found to be travelling faster than 20 m.p.h.