Limit cars' speeds: safety expert

The co-author of a South Australian road safety study has called for cars to be speed limited.

Craig Kloeden, research fellow at University of Adelaide’s Centre for Automotive Safety Research (CASR), told motoring.com.au that he was in favour of speed limiting vehicles.

"I'd be totally in favour of limiting those [cars with] very high speeds," Kloeden told motoring.com.au.

This week CASR released a 10-year study of rural road crash statistics. Kloeden was the co-author of the study.

The study has called for the blanket reduction of speed limits on the state’s rural roads from 110 to 100km/h. In interviews since the study’s release, Kloeden has suggested even further reductions would be desirable.

The study suggests the most effective way to reduce the number of injuries resulting from car crashes is to reduce speed limits.

Kloeden told motoring.com.au: "It's been shown again and again and again, by this study, that lowering speed limits works. You only have to slow drivers down by a little bit to get a big effect."

Lower speed limits are one strategy, electronically governing the speed of vehicles is another, he says. It’s also a move the CASR expert endorses.

Many cars sold in Australia are capable of surpassing 200km/h, but Kloeden says "there really is no real legal use for that".

Kloeden concedes electronic speed limiting is not likely to happen "any time soon". Instead, for now he's focussed on spreading the message that lowering the speed limits on rural roads in South Australia will reduce road trauma.

South Australia reduced the speed limit on some rural roads in 2003. It’s statistics around this change that CASR examined.

"We looked at 10 years of data, before and after the [speed limit] change, and that gave us the numbers we needed to confidently say there was an effect [to reduce road trauma].

"Taking into account long term trends and improved vehicles and things like that, we found that on the roads that had the speed limit lowered, there was a 27% per cent reduction in the number of injury crashes," he explained.

The picture isn't so clear when it comes to fatalities, the research fellow reasoning that "because the number is so small you get a lot of random variation - statistically you can't say with certainty what it is [unlike injuries]".

It's understood that the South Australian government and local councils are now looking to reduce the speed limit on more rural roads, expanding the 2003 change that affected around 1000 rural arterial roads.

While Kloeden says slowing drivers down will help reduce road trauma, he was sceptical of the merits of driver training or an improved licensing scheme.

"You get better at driving by doing lots of driving, basically," he opined.

"Generally if you look at the literature, there's no real proof driver training does anything. You can speed that up in theory by providing training, but it pales into comparison compared to just learning through doing actual driving."

The research fellow says that advanced driver training can be counterproductive "because people get to know the limits of their vehicle and once they know the limits they tend to push closer to those and travel at higher speeds and do more dangerous things".

"There was a study on racing drivers and looking at their crash rate in ordinary driving they actually had a higher crash rate than the rest of the population," Kloeden claimed.

Despite some statistics pointing to speed as the key issue in road trauma, places like Germany have a lower per capita road toll than Australia despite no speed limits on many of its autobahns. The Northern Territory's 12-month trial of unrestricted speeds on the Stuart Highway also resulted in zero road fatalities too.

Kloeden suggests the Northern Territory simply got lucky with its unlimited speeds trial, saying "It's not surprising if you have a year [with zero deaths]...  Even if [high speeds] doubles the risk there's still a good chance you'll have no fatalities there in a particular year."

When pushed on the subject of the German autobahn, he was less dismissive.

"If you've got an autobahn situation where you've got protected sides of the roads, separated traffic flows, then there is an argument that high speeds are appropriate in those situations."

But to get Australian roads to that standard "would cost billions of dollars", says Kloeden.

"In an ideal world we'd have separated roads and protected road sides everywhere. You could travel faster and still have the same injury and death rate. But given South Australia's limited population and long sections of roads with low traffic, you get the same effect from lowering the speed limit," he stated.

What are your thoughts on speed limits, driving training, licencing and electronically governing the speed in cars? Have your say below or join the conversation on motoring.com.au's Facebook page .

Image: Simon Yeo