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Mobility & Transport - Road Safety




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Estimates on the number of road accidents for which tiredness was a contributing factor vary from 10% to 24%. An exact figure is difficult to pin down as tiredness cannot be detected by an observer, but according to surveys half of drivers admit driving while drowsy at least once a year.


Whatever the numbers, falling asleep or feeling sleepy while in control of a vehicle clearly increases the risk of an accident. Also, any collisions are often more severe because the driver does not brake beforehand.

Young drivers, professional drivers and shift workers are particularly at risk of driving while tired.

What are the risks?

Tiredness affects the mind and body in more ways than you might imagine.


  • reduction in alertness
  • longer reaction times
  • poorer psychometric coordination
  • less efficient information processing


  • memory problems
  • motivation to carry out a task diminishes
  • communication and interaction with the surroundings deteriorates
  • ability to assess driving performance – or lack of – lessens
  • driver gets irritated more quickly and reacts more aggressively towards people and things

More on how tiredness affects driving

Know your body

Tiredness is not only a result of a lack of sleep. You can also feel sleepy if you are jetlagged or working unusual hours, you have had a particularly demanding day, you are ill, or the driving is monotonous – for example on a motorway. Whatever the reason, recognise the signs and take action.

  • take regular breaks – around 15 minutes every two hours
  • don’t start a long trip if you’re already tired
  • avoid driving at times when you would normally be asleep
  • share long drives if possible
  • if you feel sleepy, find a safe place to pull over, have a high-caffeine drink and wait 20 30 minutes before setting off again
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