Sunday, November 6, 2016

Hands-free Mobile Phone Drivers Roughly The Same As Drunk Drivers

Posed picture of me using mobile phone while driving
I'm sure you've seen lots of drivers driving and using their phone at the same time. I saw three drivers using their phones while standing at the back door of our clinic this morning, According to Singapore Traffic Police figures, at least eight drivers were caught using their mobile devices behind the wheel last year. Hopefully, you're not one of them.

Here's an article I found by a group of researchers comparing the effects of a variety of mobile phone usage conditions to different levels of alcohol intoxication on driving performance and vigilance.

Each participant had to complete a simulated driving task on two days, separated by a week's break. Driving performance was assessed by variables including time spent speeding, braking reaction time, time driving in target speed range, lateral lane position and speed deviation etc

On the mobile phone day, the participants performed the simulated driving task under the following four conditions. No phone usage, a hands free conversation, a hands free but cognitively demanding conversation and texting.

On the alcohol day, the participants performed the simulated driving task at four different blood alcohol concentration levels (BAC), 0.00. 0.04, 0.07 and 0.1.

Here's what they found. Under BAC 0.7 and 0.1 alcohol conditions, the participants spent less time in the target speed range, more time speeding and took longer to brake than in the 0.00 condition.

While using their mobile phones, participants took longer to brake in the hands free conversation, cognitively demanding hands free conversation and while texting. They also spent less time in the target speed range and more time speeding in the cognitively demanding hands free conversation and while texting.

When comparing both conditions, the hands free conversation was comparable to the legally permissible BAC level (0.04). The cognitively demanding and texting conversations were similar to the BAC 0.07 to 0.1 results.

According to the conclusion by the authors, simple hands free conversations while driving may not represent a significant driving risk (comparable to legally permissible BAC levels). Cognitively demanding hands free conversation and especially texting while driving represent significant risks to driving i.e. similar to when they were drunk!

In Singapore, it is currently illegal for drivers to hold any type of mobile device while driving. As long as you're holding it while the vehicle is moving you can be charged. Previously, you could not call or text on a mobile phone.

However, it is not illegal to use a mobile device if it is mounted on a holder or a dashboard. Wearable technology such as Google Glass or the Apple watch is not mentioned though.

So be safe while you're out on the roads (especially if you're cycling).


Leung S, Croft RJ et al (2012). A Comparison Of The Effect Of Mobile Phone Use And Alcohol Consumption On Drving Simulation Performance. Traffic Inj Prev. 13(6): 566-574. DOI: 10.1080/15389588.2012.683118.

Riding with one finger and giving cyclists a bad name
*Picture by Comrade King from Flickr.

No comments:

Post a Comment