Work-related road safety in South Australia

This report presents a broad investigation of work-related road safety in South Australia in three distinct parts. In the first part, a review of national and international literature on work-related road safety is conducted. The second part presents an analysis on the burden of work-related light vehicle crashes in South Australia for the years 2006 to 2010. Three separate methods of identifying work vehicles that were involved in South Australia crashes were utilised. Each of the methods identified a particular set of work vehicles which were then analysed separately. Despite this, the results from each method were reasonably consistent. Compared to non-work vehicles, the crash involved work vehicles were more likely to be newer, travel during daytime hours on weekdays, and be driven by males of working age. A large proportion of the work vehicles were found to consist of commercial-type vehicles such as utilities, vans, and station wagons, which are less likely to be fitted with safety features that are common on other light vehicles. Another finding was that work vehicles that crashed in the greater Adelaide metropolitan area between 6am and 7pm on a weekday while being driven by a person younger than 65, had a higher crash risk than non-work vehicles. No definitive reason for the increased crash risk could be identified. In the third part of the report, an analysis of the crash and injury experience of a large government light vehicle fleet in South Australia is presented. Information on the safety features of each vehicle that entered the government fleet between 1 January 1998 and 31 December 2010 were obtained, along with details on crash involvement and total travel distance. Within the government fleet, the uptake of safety features over time was similar to that of the general vehicle fleet and even greater for some features such as electronic stability control and traction control. Analysis of the crash data (while controlling for total travel distance) revealed that the crash rate of the government fleet had reduced over time. With respect to the different safety features installed on each vehicle, it was found that those vehicles that were equipped with ESC or had a 5-star ANCAP safety rating had a statistically significantly lower crash rate compared to those that were not.JRR Mackenzie, DJ Searson, RWG Anderso

An investigation of cyclist passing distances in the Australian Capital Territory

Available online 11 March 2021In Australia, cycling hospitalisations are increasing and the cycling participation rate is stagnating. In an effort to improve cyclist safety, many Australian jurisdictions have mandated a minimum passing distance that vehicles much provide when overtaking a cyclist on a public road, including the Australian Capital Territory (ACT). However, it is not currently clear how vehicle-cyclist passing distances are affected by various parameters such as the road environment, the vehicles involved, or the speed limit. This naturalistic bicycle riding study examined data from passing distance measurement devices that were installed on the bicycles of volunteer cyclists who ride in the ACT, to explore how passing distances and compliance with the minimum passing distance were affected by several parameters. Over a four-week period, 23 volunteer cyclist participants undertook 465 journeys and travelled 6531 km over a total period of 271 h. There were 10,959 passing events identified on roads zoned greater than 60 km/h (high speed roads) of which 1349 (12.3 %) were non-compliant. On roads zoned 60 km/h or less (low speed roads) there were 5517 passing events of which 153 (2.8 %) were non-compliant. Regression analyses showed that differences in passing distance and non-compliance with the minimum passing distance were associated with road classification, bike lane presence, and speed limit. The results were mixed but, in general, passing distances were greater on roads with a lower (hierarchy) classification and on motorways as well as on roads with higher speed limits. An exception to this was roads with a speed limit of 50 km/h where passing distances were closer in comparison to roads with a speed limit of 60 km/h. Bike lanes were generally associated with an increase in passing distance except on ‘trunk’ classified roads, where a bike lane resulted in closer passing events. This suggests that on trunk roads, which are assumed to carry large amounts of traffic, bike lanes may be insufficient to offer protection to cyclists and additional measures may be required.J.R.R Mackenzie , J.K. Dutschke, G. Pont

Potential benefits of autonomous emergency braking based on in-depth crash reconstruction and simulation

The objective of this study was to estimate the potential effectiveness of AEB systems using simulation of crashes drawn from Australian indepth crash data. 104 crashes that occurred within 100 km of Adelaide, South Australia, were used to assess the potential effect of AEB systems. The crashes had been investigated at the scene, re-constructed to determine collision speeds, and in this study they were analyzed using simulation to estimate how collision speeds and injury risks would have been modified by each of several AEB systems considered. Crash types considered were rear-end, pedestrian, head-on, right angle, right turn and a proportion of hit-fixed-object crashes. Other crash types were thought to be less responsive to the effects of AEB and were not considered. The variation in AEB systems were described using several parameters: the range of the forwardlooking zone, the angle or width of the forwardlooking zone, the processing time for the system to respond to the road user or object in its path (latency), the time-to-collision (TTC) at which the system would intervene, and the strength of the intervention (the level of braking). The AEB simulation used information from the trajectory of vehicles in the 104 crash reconstructions to estimate what difference each system would have made to the collision speed in each case and for each AEB system considered. Injury risk curves were used to estimate changes in fatal and injury crash risk in each case. The reductions in risk were weighted according to the rate of crash involvement of vehicles, based on the patterns of crashes in New South Wales for years 1999-2009. The overall reductions in risk produced by the various AEB systems were substantial. Systems were predicted to reduce fatal crashes by 20-25% and injury crashes by 25-35%. Note that these estimates rely on assumptions about universal operability and reliability of systems.Robert Anderson, Samuel Doecke, James Mackenzie, Giulio Pont