§ 15. Mr. Longdenasked the Minister of Transport what has been the effect on the accident rate of the imposition 421 of speed limits of 40 and 50 miles per hour in built-up areas; and whether he will now make it compulsory for motorists in such areas to dip their headlights rather than rely only upon their side-lights.
§ Mr. MarplesFrom a sample survey in the London Traffic Area the Road Research Laboratory concluded that the imposition of a 40 m.p.h. speed limit on unrestricted roads reduced the number of personal injury accidents by 19 per cent. On roads previously subject to a 30 m.p.h. limit there was no significant change in the accident rate. No 50 m.p.h. speed limit has been imposed in built-up areas.
With regard to the second part of the Question, I am now studying a report which the Road Research Laboratory have recently completed on the dipped headlight experiment in Birmingham.