The aim of this study was to estimate the likely effect of reduced travel speeds on the incidence of pedestrian fatalities in Adelaide, Australia. The study was based on the results of detailed investigations of 176 fatal pedestrian crashes in the Adelaide area between 1983 and 1991. The method developed to estimate the effect of reduced travelling speed is described, and supported by references to the published literature.

A reduction in the speed limit from 60 to 50 km/h was one of 26 speed reduction scenarios which were considered. The results for a selection of these 26 scenarios are presented in the paper. The smallest estimated reduction in fatal pedestrian collisions in the selection presented was 13 per cent, for a scenario in which all drivers obeyed the existing speed limit. The largest estimated reduction was 48 per cent for a scenario in which all drivers were travelling 10 km/h slower.

The estimated reductions in fatalities obtained in this study are compared with those observed in places where the urban area speed limit has been lowered.