One-third of the one million truck drivers on highways in the USA may be too tired to stay awake while driving or to respond quickly enough to avert an accident. Sleepiness is believed to be responsible for a large share of long-haul vehicle accidents. Undue fatigue has resulted in pilots' failing to read gauges correctly and landing not only on the wrong runway but even at the wrong airport. Many major industrial accidents occurred at night when it is probable that workers were not optimally alert.
A survey of 200,000 workers in 10,000 private companies in Japan in 1982 showed that 72.8% of male workers complained of mental fatigue and 64.7% of physical fatigue caused by their job. The corresponding figures for female workers were 65.5% and 64.5%.