The economic burden as well as the social burden from road crashes is staggering. In high income countries such as Australia, the driver and passenger are typically the victims of road crashes. There are not only psychological and physical consequences for the injured person, road crashes also impact on the lives of families and communities. It has recently been acknowledged that in Australia road trauma can be reduced by enforcing the use of safer vehicles, promoting community acceptance of a low tolerance for risky driver behaviour, and improving Australia’s road transport system (1). Rural crashes on the Australian road transport system are a major and persistent crash concern and are distinct to urban crashes. Urban areas characteristically have higher traffic density, more conflict points and higher-density living compared to rural areas. However, there is evidence to suggest that in rural areas of Australia, road crashes result in more severe injuries and are more likely to result in a fatality compared to crashes in urban areas (2). Data from the United States have indicated a similar pattern with injury fatality rates reported to be up to three times higher in rural areas compared to urban areas (3). The injuries are typically more severe in rural areas due to factors such as, higher impact speeds and slower access to after-crash treatment. Road user factors such as speed, alcohol, fatigue and lack of restraint use also contribute to increased injury severity in rural areas. These road user factors can be differentiated into inadvertent errors and unsafe driver behaviours. In particular, the incidence of serious casualty run-off-road crashes in rural Western Australia is significant. High-speed, alcohol consumption, lower incidence of seat belt wearing contributes to this crash concern. Long monotonous routes with little traffic and little stimuli further exacerbate the situation, creating ready conditions for fatigue, drowsiness and driver error. A main challenge in creating road designs to minimise such crash occurrence and crash consequence is anticipating and accommodating driver error - be the errors inadvertent or arising from deliberately unsafe behaviours. Behaviour change programs have been successful in the past but their effects are slowing and it is timely to seek new ways of designing and operating roads to accommodate the inevitable human errors. This study was completed to explore the crash situation in regional and remote WA within the context of driver error. It seeks potential countermeasures available through literature to address the identified crash problems and create a safer road environment for travel through rural WA. The objectives of the study were: • To assess the respective roles of inadvertent errors and unsafe driver behaviour — specifically, speed and speeding in rural road crashes in WA; and • To identify road design features which aim to minimise the occurrence of inappropriate speeds, as well as driver error and its consequences. Task 1 — Literature Review on Errors. A literature search was undertaken to identify from the available research, the range of errors underlying key serious casualty crashes in rural areas. So far as the literature permitted, these errors were classified as either (i) inadvertent or (ii) arising directly from deliberate, unsafe behaviours. The potential role of travel speed, inattention and fatigue as a source of error was examined in particular. Task 2 — Analysis of Crash Data. The initial literature search was supplemented by an analysis of crash data provided by WA Main Roads to identify the typical serious casualty crashes occurring on rural roads in WA. Task 3 — Literature Review on Road Design Features. A second literature search was conducted, this time focussing on road design features and their capacity to reduce driver errors and/or the consequences of those errors. Design features which aim to produce compliance with posted speed limits and safe travel speeds were targeted. The list of identified design features were categorised under the range of inadvertent errors and deliberate non-compliance. It is noted that much literature exists on the various safety issues relating to rural safety. As well, many studies and literature reviews have been completed on the effectiveness of some of the measures trialled. Both literature reviews are not considered to be exhaustive in highlighting the relevant literature in this report. Instead, the reviews focussed on presenting a summary of the issues that exist and many of the countermeasures available. Task 4 — Workshop and Development of a Taxonomy of Behaviour. The list of driver errors and road design countermeasures were presented at a half-day workshop attended by available stakeholders, with a view to developing a prioritised suite of road design improvements and countermeasures. Presentation of identified countermeasures and the practicality of implementation were discussed at the workshop as were other available treatment options. Treatments were presented with respect to Safe System and non-Safe System compatible measures. A taxonomy of behaviour and potential countermeasures was developed in regard to the key crash problem of WA rural region - single-vehicle crashes. The taxonomy attempted to readily categorise the driver error as well as the related design error and list potential countermeasures that can be utilised by traffic engineers as well as policy makers, to address this crash type in a systematic approach. It was presented also as a template to help facilitate treatment of other high priority crash types. (Author/publisher)
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