The potential dangers of Sat-Nav

Stories are mounting up of trucks ending up on inappropriate roads after relying on sat-nav guidance - but is using this driver aid also a deadly distraction?  A growing number of news articles about trucks being led astray by satellite-navigation systems suggests an increasing reliance on in-cab technology that wasn't designed for LGVs. Now, concern is growing that this technology could also be a dangerous diversion itself.

A Swedish study recently found that control of a vehicle by its driver deteriorated significantly when using In Vehicle Information Systems (IVIS). Most people agree that physically attending to any form of IVIS while at the wheel, whether tuning a radio, answering a phone or punching buttons into a sat-nav system, is unsafe. But the research indicated that even spoken commands affect a driver's concentration, leading to reduced speed control and increased risk of tailgating.

Road-safety campaign group Brake says this proves that reading a sat-nav system while driving is potentially as dangerous as using a mobile phone. However, the organisation isn't against guidance systems as such. Referring to a Department for Transport consultation on sat-nav technology, a spokeswoman says: "Brake called for a compulsory licence for companies producing in-vehicle routing systems, such as sat-nav. Brake proposes the licence would only be granted to companies whose products meet certain safety criteria, such as not having a screen, which can cause a distraction to drivers, and relying instead on oral instructions only."

But not everyone agrees with these proposals. Freight Transport Association policy director James Hookham says: "I think that's a bit of overkill. I don't quite understand the logic of that. So you can't look at your speedometer, then? "If you think you are going to be distracted, you should stop. I don't think the advancement of technology in goods vehicles should be halted just because drivers should engage their brains."

This view is supported by the Road Haulage Association and the Royal Society for the Prevention of Accidents (Rospa), although a spokesman for the latter adds: "Just having the spoken instructions might be a way of reducing distractions. Different people are distracted by different things. We would call on satellite navigation to be made less distracting." A popular view is that drivers should use their common sense, treating sat-nav as they would a radio or CD player and not allow themselves to be distracted.

Accuracy

The debate over sat-nav safety has only just begun, but another issue raised many times in the press relates to their accuracy. And on this subject, everyone agrees: drivers are relying far too much on guidance systems. Hookham says: "We are getting fed up with stories in the press about trucks going down wrong and inappropriate roads, simply because drivers are following what their sat-nav is telling them." The reasons for this are understandable enough - too much faith in technology laziness unawareness that new data must be downloaded regularly and, anecdotally, a proliferation of foreign drivers who are clueless about UK roads and forced to rely on technology designed for cars. But that may be about to change.

Ordnance Survey, Pie Enterprises and Navteq all say they are designing maps specifically for trucks, including weight, height and width restrictions, steep hills and sharp curves.

For now, though, questions remain about how safe it is to have complex and distracting communications systems in truck cabs. No-one we spoke to, other than Brake, believes sat-nav is as dangerous as using a mobile phone, and few had heard about the Swedish research. But as an Ordnance Survey spokesman points out: "Some years ago, people didn't realise how dangerous it was to use mobile phones on the road. But that's becoming increasingly known now."

Government consultation

Last autumn the government began a consultation into legislation developed in 1989-1990 that required system providers to apply for a licence prior to marketing sat-nav devices. This stated: "As the use of satellite navigation becomes more common, there is a need to ensure that the devices do not pose a safety risk through driver distraction. It is also necessary to ensure that their routing strategies do not encourage the use of 'rat runs' or give ill-advised or illegal instructions to the user."

A Department for Transport spokesman expects a summary of its findings to be published by the end of the year. Dangers and poor route guidance aside, the cost of relying solely on sat-nav and sending your vehicle down inappropriate roads can add up. RHA infrastructure manager Chrys Rampley points out: "There's the delay to the delivery to start with, and perhaps the cost of pulling it out with a recovery vehicle. Then there's damage - cost of repairs, problems with a bridge or a house. And there's the effect on a company's image! People rely on sat-nav too literally. Rather than using it as an aid, they tend to ignore the road signs. Directions from in-vehicle systems shouldn't be taken as gospel."

As the use of satellite navigation becomes more common, there is a need to ensure that the devices do not pose a safety risk through driver distraction. Effects of Cognitive and Visual Load in Real and Simulated Driving, an investigation by VTI, the Swedish National Road and Transport Research Institute, involved various tests on candidates in road-related experiments. Drivers were monitored during visual and cognitive, or auditory, exercises.

Candidates' driving performance was analysed during three increasingly difficult situations in motorway and rural road environments. The tasks were designed to represent the demands imposed by IVIS (In-Vehicle Information Systems) such as route guidance, mobile phones and radios. After studying the evidence, the exercise proved that visual tasks adversely affected driver performance to a greater degree than auditory tasks. In conclusion the VTI noted: "The cognitive [auditory] and visual tasks affected driving performance differently. The visual test primarily affected lateral control, but to some extent also the interaction with other road users. The participants slowed down in order to compensate for the increased visual demand, but seemed to become too distracted even to manage that task - there were strong indications that the longitudinal control deteriorated for the most difficult visual task level. The cognitive task also resulted in somewhat decreased speed control, but did not slow down at all."

It added that the cognitive task resulted in increased 'lateral stability' (the distance between the front wheel and the centre line), suggesting that drivers were either making a conscious effort to stabilise control or that their visual resources directed to the tracking of the road ahead were increased. Whatever the reason, the authors warned that decision-making performance can deteriorate.