I know that in North Carolina (I lived there a year and had to get a new license during that period) there's a section of the driving handbook that covers drowsy driving.

Here's some info from drowsydriving.org > "According to a study by the AAA Foundation for Traffic Safety, people who sleep six to seven hours a night are twice as likely to be involved in (such) a crash as those sleeping 8 hours or more, while people sleeping less than 5 hours increased their risk four to five times."

http://drowsydriving.org/about/facts-and-stats/ http://www.ncsl.org/research/transportation/summaries-of-cur...