Study finds hands-free calls are just as distracting for drivers

Talking on the phone, be it hand-held or hands-free, has been found to significantly increase driver reaction times
Talking on the phone, be it hand-held or hands-free, has been found to significantly increase driver reaction times
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Talking on the phone, be it hand-held or hands-free, has been found to significantly increase driver reaction times
Talking on the phone, be it hand-held or hands-free, has been found to significantly increase driver reaction times

When the calendar ticks over to 2017 on Sunday, California drivers will no longer be able to hold their phones while driving for any reason. That includes talking, texting, snapping photos or video, or using the phone as a GPS. Drivers will only be able to use their phones in hands-free mode. However, a new study out of the Queensland University of Technology (QUT) in Australia suggests the law doesn't go far enough, because hands-free operation isn't any safer.

The dangers of texting while driving are already well established, with texting or making calls on a hand-held phone illegal in many countries around the world. It's been widely accepted that making calls hands-free while driving is a safe option because both of the driver's hands are free to remain in control of the car, but the road safety study conducted at QUT indicates that the mental distraction is just as great during calls on both hands-free and hand-held devices.

The study conducted by Dr Shimul (Md Mazharul) Haque used the Centre for Accident Research and Road Safety – Queensland (CARRS-Q) driving simulator to measure the effects of using a mobile phone on reaction time and driving performance.

"We took a group of drivers and exposed them to a virtual road network which included a pedestrian entering the driver's peripheral vision from a footpath and walking across a pedestrian crossing," says Dr Haque. "We then monitored the driver's performance and reaction times during hands-free and hand-held phone conversations and without."

For drivers conducting a conversation using either a hand-held or hands-free mobile phone, driver reaction time was over 40 percent longer than those not using a phone at all. For a vehicle traveling at 40 km/h (25 mph), Dr Haque says this equates to a delayed response distance of about 11 m (36 ft).

"This shows hands-free and hand-held phone conversations while driving have similar detrimental effects in responding to a very common peripheral event of a pedestrian entering a crossing from the footpath," says Dr Haque. "It appears that the increased brain power required to hold a phone conversation can alter a driver's visual scanning pattern."

According to Dr Haque, when extra information is sent to the brain during a conversation, it compensates by not sending some visual information to the working memory. This results in distracted drivers looking at, but not "seeing" some objects. He also points out that conversations on a phone and passengers in the car differ, because the passenger can take into account the driving environment and stop talking when approaching a complex driving situation, for example.

The study also showed the reaction times for those with provisional driver's licenses was doubled compared to those with full licenses and that drivers engaged in a phone conversation braked more abruptly, which can pose a risk to following vehicles.

Dr Haque believes the findings of his study raise questions in relation to mobile phone laws that allow drivers to conduct phone calls with hands-free devices. But given how common it is to see drivers with phones pressed against their heads in places where that is illegal, you have to wonder how much harder it would be to police a law that banned the use of hands-free devices – even if there were governments willing to enact such laws. Autonomous vehicles may be the only viable answer – and that opens another can of worms entirely.

Source: QUT

Anne Ominous
This is very far from the first study to come to this conclusion. That there is no significant statistical difference in distraction between hands-free calling and holding the phone to your ear has been known for many years now. Certainly I've known about it, and I'm not a researcher in the field. You might also be interested to know that there is no statistical correlation between talking on cell phones and accident rates. Regardless of whether the phone is in the hand, or hands-free. That has also been known for a very long time now.
Anne Ominous
I just found an old blog post of mine on this exact subject, mentioning the recent research... from June 2010. Six and a half years ago.
Yet more effort wasted on a simple observation! Any distraction to a driver equates to reduced alertness and increased risk of incident.......children squabbling in the back, high tempo/aggressive loud music, messing with on board navigation or vehicle control panel, phone calls, passenger who doesn't/can't understand when not to talk and distract the driver, rubber necking at accidents, eye catching advertising bill boards.................the list is as long as your imagination. Assuming driverless cars are years away for the majority, for my mind if you want to reduce distractions then revert to the era of non-smart cars, put a phone jammer in every car during manufacture but best of all educate and penalise. Don't waste police time chasing phones attached to ears or using hands free. It is easy enough to find out if a driver has been involved in a phone call immediately prior to an accident. Irrespective if they are perpetrator or victim of the crash then fine them punitively at a level set against their means. After a few times of people losing a months wages and 10% of their savings the impact on others would, I suspect, be huge.......draconian, yes, effective probably.
Peter Kelly
Of course such things are distracting. Absolutely terrible! But I'm sure we'd hear absolute drivel about how the Police are highly trained as they cope with their radios, ANPR cameras, computers, radars, etc. and so it doesn't affect them while driving... The simple truth is that anything, absolutely anything can and will distract. What matters is how you temper your behaviour to make such distractions of minimal impoartance.
Somebody has suggested building a phone blocker into every new car. This seems like a good idea, but how long before one is able to buy a device or download an app which will 'unblock' the car? I think the only way to reduce driver's use of phones is by constant re-education to make this habit socially unacceptable in the same way drink driving is.
Where is the study on drivers talking to their passengers? How is it any different than a hands free device?
When they did these tests did they also include people talking to the driver? If so what was the reaction time in that case and how does it compare with a hands-free phone call? If they didn't were they trying for the specific results they got? Something which does not appear very scientific.
Reaction time, reaction time, reaction time, reaction time, reaction time. No evidence linking reaction time to significant increases in accident rates. Interestingly this sort of flim-flam used to link increases in reaction times to the equivalent levels of alcohol ingestion to justify the reaction-time-bad rhetoric. It appears this is no longer necessary and the public only needs to read the phrase reaction time to conclude that something is conclusively bad.
It is not difference talking to hands free phone as to any passenger in the car. Sometimes driver is not responding to conversation to stay concentrating on road event. Therefore on some buses passengers are not allowed talk to driver during driving. Finally, any sound can distract driver as loud adverts from the car radio, which often are very annoying too. Then am changing radio channel, lowering sound, or switch off.
amazed W1
I submit that it is the content of the in-car conversation or phone call that causes the dangers. Phones slightly worse because more likely to involve the employer, client or awkward spouse ringing from Home. Real intellectual and emotional involvement is inevitable where a casual conversation does not. Remember those early notchy power steering systems that meant you had to think instead of allowing eye-hand coordination to deal with 95% of road situations?.