No such thing as safe text 18 Sep 2008

Texting behind the wheel impairs driving skills more than being drunk or high, according to new research carried out by TRL for the Royal Automobile Club Foundation, published today (18). Despite the danger, 48% of UK drivers aged 18 - 24* admit to using short message services (SMS) whilst driving - a group already at much higher risk of being involved in a crash.

Publicity and legislation has to date focused on the risks of speaking on a mobile phone while driving, overlooking the fact that phones are also used for texting, picture messaging and web surfing. Nearly 5,000 texts are sent every second in the UK**.

The RAC Foundation is calling for urgent investment in a high-profile education campaign, designed to raise awareness among those young people who have grown up with mobile phones, that texting and driving puts themselves, their friends, and other road users at unacceptable risk.

Carrying out the first UK research into the effects of texting while driving, the RAC Foundation and TRL used TRL's driving simulator to research the effects of writing, reading and ignoring text messages on the driving skills of a test group of 17 - 24 year old motorists. In all key measures of driving performance, young people who were texting and driving were badly affected:-

  • reaction times deteriorated by over one-third (35%). This was worse than alcohol at the legal limit (12% slower) and driving under the influence of cannabis (21% slower)
  • drivers drifted out of their lane more often. Steering control was 91% worse, compared to 35% worse when under the influence of cannabis.
  • the ability to maintain a safe following distance fell.

TRL's experts concluded that "In real world traffic situations, it is suggested that poorer control of vehicle speed, lateral position, and increased reaction times in this situation would increase the likelihood of collision dramatically."

Comparing the level of distraction caused by texting to previous TRL studies*** into the impairment effects of drugs, alcohol (at the legal limit) and speaking on a mobile, the report concludes that texting had the greatest impact on lane positioning; and the second greatest impact on reaction times, second only to using a hand-held phone, making texting while driving more risky than driving while on drugs or under the influence of alcohol.

The RAC Foundation is not calling for new laws as a result of the research: while a loophole in the current law means that texting could be legal provided the phone is in a cradle, a driver who is deemed not to be in proper control of their vehicle because they are distracted can already be given a fixed penalty of £60 and three penalty points. If a driver is involved in an incident or a crash while texting on a phone, the Crown Prosecution Service has said that a charge of dangerous driving will be their starting point. There must, however, be high-profile enforcement of these laws, leading to prosecutions where appropriate. ****

All participants in the study described themselves as confident texters. Despite this, messages, which at a desk took an average of 22 seconds to compose, took on average 63 seconds when the texter was also driving. In one minute, a car travels half a mile at town centre speeds and over a mile at motorway speeds. During this minute, drivers are distracted in three ways:-

  • mental workload: the work of composing the text takes the mind off the road
  • control: using the phone's keypad means that only one hand is on the wheel
  • visual attention: eyes are on the phone not on the road ahead

The key consequences found by the study were:-

  • Slower Reaction times: participants were asked to react to a buzzer or a visual cue which would appear on the screen of the simulator. Writing a text message had the biggest impact on reaction times, increasing them from 1.2 seconds to 1.6 seconds. At motorway speeds, this would mean travelling an additional three car lengths before beginning to brake. Some participants missed the visual trigger completely. TRL notes "the failure to detect hazards and increased response times to hazards has clear implications for safety."
  • Inability to maintain safe following distance: tailgating causes one-third of injury accidents on the motorway network. A safe following distance is vital to road safety. Participants were less able to maintain a safe distance behind a lead vehicle, and also strayed out of lane position behind it, when distracted by a texting task.
  • Inability to hold lane position: participants' tendency to drift out of their lane while trying to write a text increased by 91.4% compared to a "control drive" where they were concentrating on the driving task. In busy dual carriageways and motorways, drifting out of position is a serious hazard, while in a town centre or rural road losing position might result in a collision with a pedestrian, cyclist or motorcyclist.

TRL conclude: "the combination of increased mental workload required to write a text message, the control impairment caused by the physical act of holding the phone, and the visual impairment caused by continually shifting visual orientation between the phone display and the road ahead resulted in significantly impaired ability to maintain safe road position."

Professor Stephen Glaister, Director of the RAC Foundation, said: "The participants in this study were almost unanimous in their view that drink driving was the most dangerous action on the road. Yet this research clearly shows that a motorist who is texting is significantly more impaired than a motorist at the legal limit for alcohol. No responsible motorist would drink and drive. We need to ensure that text devotees understand that texting is one of the most hazardous things that can be done while in charge of a motor car."

Dr Nick Reed, Senior Human Factors Researcher at TRL, said: "This research demonstrates how dangerous it is to drive and text. When texting, drivers are distracted by taking their hand off the wheel to use their phone, by trying to read small text on the phone display, and by thinking about how to write their message. This combination of factors resulted in the impairments to reaction time and vehicle control that place the driver at a greater risk than having consumed alcohol to the legal limit for driving."


* RAC Foundation poll of 2002 Facebook users.

** Mobile Data Association report, February 2008.

*** Full details of the comparative impact of different impairments: