Reporting on the survey, Bloomberg said that the poll of 1,154 adults was taken in October and November 1999 and has a margin of error of plus or minus 3 percentage points. Seventeen percent of those polled said they had fallen asleep while driving in the past year. Sleepiness slows reaction time, decreases awareness and impairs judgment. A surprising number of people are tired because they have a sleep disorder. The effects of driving drowsy mimic the effect of driving drunk.
Coffee overcomes the effects of drowsiness while driving.
I can tell when I'm going to fall asleep. I can't take naps. I get plenty of sleep. You can sleep when you're dead. Most people think this is true.