Among professional drivers

The results of different surveys world-wide (Australia, France, Ireland, Netherlands, USA) show that over 50% of long-haul drivers have at some time almost fallen asleep at the wheel [32]. A survey among Dutch, German, Belgian, Danish and Italian long distance truck drivers provided the following results on fatigued driving [87]:

• 43% sometimes almost fall asleep, but have never actually fallen asleep
• 9% actually have fallen asleep but never had a crash
• 7% actually had a crash caused by falling asleep behind the wheel.

In total 60% of European truck drivers reports to almost have fallen asleep. Van Ouwerkerk [86] reports similar figures for USA (64%), Australia (60%) and Ireland (45%).

A Finnish survey research [45][46] amongst 317 male truck drivers showed that especially long-distance drivers had regularly to deal with fatigue while driving; over 40% reported dosing off in the past three months and about 25% reported this to have happened twice in the same period. In contrast, among short-distance truck drivers, only 15% reported dosing off behind the wheel in the past 3 months.

In several studies of European professional drivers (both car drivers and truck drivers), it was demonstrated that long-distance driving often goes together with reduced sleep duration [91]:

• In one study of 567 car drivers, 50% had reduced their normal sleep in the 24 h before departure for a long-distance journey and 10% had no sleep in the 24 hours before the interview;
• In another study of 2197 car drivers, again 50% of the drivers decreased their total sleep time in the 24 h before the interview compared with their regular self-reported sleep time, and 12,5% presented a sleep debt > 180 minutes and 2.7% a sleep debt > 300 minutes;
• In a study on truck drivers, of 227 drivers 12.3% had slept less than 6 h in the 24 h previous to the interview and 17.1% had been awake more than 16 h.

A survey of 573 long-distance truck drivers travelling on New York interstate highways, indicated that 47% of the drivers had ever fallen asleep at the wheel of a truck, and 25% had fallen asleep at the wheel in the past year [74].

See also the section about risk groups – professional drivers.