50kph limit

50 km/h General Urban Speed Limit

ACRS Policy Position

ACRS supports a general urban speed limit of 50 km/h.   ACRS supports this measure both because of safety benefits and because it represents best practice of the majority of developed motorised nations.   However, Australian jurisdictions that have adopted or permitted the application of a 50 km/h urban speed limit have not done so in a uniform manner.   ACRS supports 50 km/h as the default general urban speed limit.

In practice the limit of 50 km/h would only apply in residential streets.   'Special' areas such as school zones and the like could be zoned to lower speeds; feeder and arterial roads and freeways with main functions other than residence or retail/commercial and not involving significant pedestrian movement may be zoned to higher limits, much as is the case at present in many urban areas.   But such zoning must be done according to a uniform and rational set of principles or warrants and be applicable across Australia

Australian Transport Council voted in November 1996 to retain the present general urban speed limit of 60 km/h in the national road rules, at least for the time being.   The Australian College of Road Safety is disappointed in this decision given the safety benefits to be expected from the lower urban speed limit and already realised in Victoria, Queensland and WA, and a wide measure of public support.   ACRS commends efforts of jurisdictions to move toward 50 km/h, but urges that uniform practice and application be adopted.

Objective

To improve the safety of urban areas in Australia, especially for pedestrians and unprotected road users.

Discussion

Speed limits are the one road safety measure that reduces both the frequency of road crashes and the severity of road trauma.   By far the majority of developed motorised nations have a general urban speed limit of 50 km/h (or 30 mph).   There is a body of research evidence that shows that a reduction of 10 km/h in vehicle speeds can make a significant difference to the incidence and severity of pedestrian injuries.   An Australian experimental study [Kloeden et al, 1997] demonstrated that a car braking from 50 km/h stopped short of an obstacle that it struck at a speed of approximately 25 km/h when braking from a speed of 60 km/h.

It is an integral part of the policy that a general urban speed limit of 50 km/h goes in hand with a system of speed zoning of urban roads according to function (see separate policy statement on Speed Management).   Feeder and arterial roads would be zoned at speeds that reflect their function, and probably at much the same limits as at present.  

The 50 km/h limit will be the general limit for all urban areas, with streets and roads zoned above and below 50 km/h as appropriate.   If 50 km/h is the 'default' limit for urban areas, roads with a different limit will be signposted.   This is the College's preferred position.

A general urban speed limit of 50 km/h has many benefits and few disadvantages.   The main benefit is the safety improvement that is the main reason for encouraging lower urban speeds.   Lower emissions and fuel consumption may also result. 

One obvious and possible disadvantage is lengthening of travel times.   An Austroads study [ref] has demonstrated that the increase in travel time would be negligible, since the lower speed limit would not apply to that part of urban travel that is on arterial roads and freeways.

In addition there are implementation costs (signs and markings, publicity and education) and the need for enforcement to increase compliance with the changed speed limits.

Reference

Kloeden CN, McLean AJ Moore VM and Ponte G (1997) Travelling speed and the risk of crash involvement, CR172, FORS Canberra