Strictly enforced speed limits could have a ‘detrimental impact on road safety’, according to new research from The University of Western Australia (UWA).
The study took place after the government in Queensland, Australia began issuing fines to motorists caught driving as little as 1km/h over the speed limit.
It concluded that when they are aware of strict limits, drivers dedicate more attention to monitoring their speed than detecting hazards.
The researchers used a driving simulator to test whether lowering speed enforcement thresholds would impact on a driver’s mental and visual abilities. 84 young adult participants drove under conditions where they could be fined for travelling one, six, or 11 km/h over a 50 km/h speed limit.
A ‘peripheral detection task’ was used to measure drivers’ mental and visual workload. They also filled out a questionnaire which asked how difficult or demanding they found the experience of driving under the different enforcement conditions.
The study says stricter speed limit enforcement led to drivers rating the experience as ‘more demanding’ with a ‘significant negative impact’ on peripheral vision and the ability to detect objects outside the driver’s immediate line of sight.
Dr Vanessa Bowden, lead researcher on the study, said: “Similar effects have been shown for individuals who drive while talking on a phone or operating their car’s stereo.
“Our overall finding was that stricter speed enforcement may impair a driver’s ability to detect hazards, especially those on the side of the road, because drivers are dedicating more attention to monitoring their speed.
“In reality the effects of strictly enforced speed limits could be even greater than in our study, with real-world drivers experiencing greater pressures to drive at or above the posted speed limit.”
The researchers plan to continue this line of study to see whether drivers are actually poorer at responding to hazards under conditions where speed limits are strictly enforced.