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Tiredness and microsleep

Tiredness lengthens your reaction time and can cause microsleep: you fall asleep for a few seconds without noticing. Signs are yawning, heavy eyelids, not remembering the last few kilometres and drifting in the lane. Coffee and an open window help only briefly. The only real cure is to stop and sleep.

s = v \cdot t

the distance you travel blind during microsleep

Symbols

$v$	speed	m/s
$t$	time asleep	s

Example

You fall asleep for 3 seconds at 90 km/h ( $v = 25$ m/s).

$s = 25 \cdot 3 = 75$ m without control of the car.

Take a break at least every two hours on long trips, and stop as soon as you notice the first signs.

Practise alcohol, fatigue and attention for free →

← Blood alcohol and burn-off · Eyes off the road →

Part of Car licence (class B): Alcohol, fatigue and attention.