Evaluation of the South Australian default 50 km/h speed limit

Abstract

On 1 March 2003 the default urban speed limit in South Australia was reduced from 60 km/h to 50 km/h. On-road speeds just before the default limit was introduced were compared with speeds a year later. The numbers of casualty crashes and casualties in the year before the default limit was introduced were compared with the corresponding numbers in the first year that the default limit was in effect. On roads where the speed limit was reduced from 60 km/h to 50 km/h, average vehicle speeds decreased by 2.3 km/h and casualties by 24 per cent. On roads where the speed limit remained at 60 km/h, average vehicle speeds decreased by 0.9 km/h and casualties by 7 per cent.