Driver behaviour

Impairment due to alcohol and drugs is a major contributor to people losing their lives and being seriously injured on South Australian roads. Alcohol impairs skill and decision-making and increases confidence and aggression. It can also lead to an increase in other risk-taking behaviour.

Almost one in five drivers and riders (19%) who lost their lives on our roads recorded an illegal Blood Alcohol Concentration (BAC) while more than one in five (21%) was drug driving. Combined, this equates to one in three drivers who lost their lives in road crashes in South Australia over the past five years testing positive to drugs and/or alcohol. The number of drivers and riders who have lost their lives while drink-driving has declined over the last decade, however the trend line has remained unchanged for drug driving.

The 20-to-29-year-old age group represents the largest percentage of the population of drivers and riders with an illegal BAC losing their lives (29%) or being seriously injured (28%). They also represent the largest percentage of the population of drivers and riders killed that tested positive for drugs (33%).

Drink and drug driving is often accompanied by other dangerous behaviour

Of the drivers killed that had a BAC of 0.05 or above, 54% were not wearing their seatbelt and 8% of rider fatalities who lost their lives were not wearing a helmet. For non-drink drivers, 19% of fatalities were not wearing a seatbelt, and 4% of riders were not wearing a helmet.

Of the drivers who lost their lives and tested positive for drugs, 43% were not wearing their seatbelt at the time of the crash and 17% of riders who tested positive were not wearing a helmet.

Driver distraction (or inattention) is a significant issue in road safety. Distracted driving refers to any activity that takes a driver’s attention away from the task of driving safely. Distractions can be inside a vehicle (e.g. mobile phone use, eating or drinking, navigation devices, passengers, reaching for objects), outside a vehicle (e.g. other road users, billboards) or from the driver’s own mind (e.g. daydreaming, emotional stress). Road users other than drivers may also be distracted, including pedestrians crossing roads, cyclists and motorcyclists.

Research indicates that taking your eyes off the road for two seconds doubles the risk of a crash.⁹

It is difficult to identify crashes involving distraction, but a recent study revealed that inattention was a contributing factor in at least a third of crashes investigated where a life is lost or a person sustains an injury in South Australia.¹⁰ In-vehicle distractions were found to be most prevalent. Inattention crashes were most likely to involve right turn/angle or rear-end crash types and occur at intersections, in metropolitan areas, and in lower speed zones.

Vehicle travel speeds affect both the risk of crash involvement and the severity of crashes, and subsequent injuries. A recent travel speed survey¹¹ indicated between 12% and 37% of motorists state-wide are not complying with posted speed limits, increasing their risk of being involved in a crash.

The risk of a crash where a life is lost or a person sustains an injury approximately doubles with each 5 km/h increase in travel speed above the limit on a 60 km/h speed limited road,¹² or with each 10 km/h increase above the average speed on higher speed regional roads.¹³

Inappropriate or excess speed was a contributing factor in 31% of all crashes where lives were lost and 26% of crashes resulting in serious injury. Inappropriate speeds that are too fast for the conditions are not necessarily above the speed limit.

While fatigue is often ranked as a major factor in road crashes, its contribution in individual cases is hard to measure and is often not reported as a cause of crash. Analysis of South Australian crash data suggests fatigue is on average a factor in around ten crashes, resulting in lives lost each year.

Research has shown that not sleeping for more than 17 hours has an effect on driving ability the same as a Blood Alcohol Concentration (BAC) of 0.05. Not sleeping for 24 hours has the same effect of having a BAC of 0.10, double the legal limit.¹⁴

Wearing a seatbelt doubles your chances of surviving a serious crash. The most recent observational survey of restraint use in South Australia¹⁵ found around 97% of vehicle occupants wore seatbelts. However, seatbelt wearing rates are much lower for crashes where vehicle occupants lose their lives or are seriously injured, particularly in regional and remote areas. Around one quarter of all drivers and passengers who lost their lives were not wearing a seatbelt at the time of the crash. Of these, 71% of crashes occurred in regional areas.

Non-seatbelt use in crashes is often associated with other dangerous behaviours (e.g. drink-driving).

The incorrect restraint of children travelling in vehicles, or children moving to the next restraint category too soon, is a concern. In South Australia, between 2005 and 2018, 38 children aged 0 to 12 years lost their life while passengers in a vehicle. 61% (24) of these children were not appropriately restrained, including nine children who were unrestrained. Of these 24 children, almost half (11), were aged 8 to 12 years and seated in an adult seat despite being less than 145 cm tall (the tallest child was 140 cm).¹⁶

The correct use of approved child restraints and the correct installation could greatly improve child safety in vehicles. While the Australian Road Rules are specific about what type of restraint is to be used at different ages, children grow at different rates. It is important to improve and maintain public understanding about the correct installation and the selection of the right restraint or booster seat, particularly for children aged 7 to 12 years of age and children with a disability.

In 2018–19 more than 600 police cautions/fines were issued to drivers failing to safely restrain passengers under 16 years.¹⁷

The safety of children in driveways is also a concern. Small children are at risk from moving vehicles in low-speed, off-road locations such as driveways, yards and car parks. One child, often a toddler, is run over in their driveway every week in Australia. On average, seven children are killed each year in Australia and 60 seriously injured after being hit or run over by a motor vehicle at home.¹⁸