RAC Foundation (2008) reported the results of a survey of 2,000+ users of Facebook, showing that 45% of UK drivers engage in texting whilst driving. The RAC Foundation commissioned TRL to study the impairment caused by texting whilst driving using TRL’s driving simulator.
Seventeen drivers (aged 17-24 years) took part in the study. Drivers completed one drive as normal (undistracted) and one drive in which they completed text messaging tasks. Participants were impaired in their performance when reading and writing text messages, particularly reaction time and ability to maintain lateral vehicle control. Reaction times were around 35% slower when writing a text message. Earlier studies at TRL showed that alcohol consumption to the legal limit caused a 12% reaction time increase; cannabis slowed reaction times by 21%. When texting, drivers slowed significantly, indicating that they recognised the impairment, attempting to mitigate risk by reducing speed. However, greater lateral variability in lane position and drifting into adjacent lanes when texting are not mitigated by speed reduction and would lead to potential conflict with other traffic.
Female drivers showed greater variability in lateral lane position when texting than male drivers. However, female participants tended to show greater speed reductions, indicating that they may have had greater awareness that their driving was impaired.
This study highlighted that when texting, a driver may present a greater accident risk than when at the legal limit for alcohol consumption or when under the influence of cannabis, reinforcing that drivers should refrain from this dangerous activity.

Want to know more about this project?