Road Safety Benefits of Intelligent Speed Adaptation for Australia

Intelligent Speed Adaptation (ISA) refers to in-vehicle technology systems which assist drivers to keep to or below the speed limit. In 2009-2010 the NSW Centre for Road Safety conducted the NSW ISA Trial which was the largest road safety technology trial ever conducted in Australia. Over 110 light vehicles from private and company fleets were fitted with an Advisory ISA device and a speed data recorder. Over 7.6 million vehicle speed data records were collected and analysed to measure changes in drivers‟ speed compliance. The Advisory ISA system reduced speeding in 89 per cent of trial vehicles. The median probability of speeding was also reduced by almost 30 per cent. Initial modelling suggested that if all vehicles in NSW were equipped with the Advisory ISA system trialled, road deaths would be reduced by 8.4 per cent and the number of people injured would be reduced by 5.9 per cent. Results of the trial demonstrated that Advisory ISA technology has the potential to realise substantial road safety benefits by increasing compliance with speed limits. This paper presents further findings of the trial and additional crash reduction benefits and community savings attributed to this technology. The analysis includes the impact of Advisory ISA at various vehicle penetration levels within Australia as well as the estimated reductions in the number of serious injury and fatality crashes in future years. Background Speeding is recognised as a significant road safety issue both in Australia and internationally. In NSW, approximately 40 per cent of all fatal crashes have speed as a contributing factor. On average, approximately 200 people die each year in NSW as a result of being involved in a speed related crash (RTA 2011). International research has found a clear relationship between changes in average traffic speed and crash outcomes (ATC 2011). Furthermore, the research suggests that even small reductions in speed will yield substantial safety benefits. The Nilsson power model shows that the number of fatal crashes will increase in proportion to the fourth power of an increase in