Most Montana residents are aware that driving when sleep-deprived can be just as dangerous as doing so when impaired by alcohol, but studies suggest that knowledge alone is not enough to prevent them from engaging in this dangerous behavior. Fatigue is thought to be a factor in about 16 percent of all fatal crashes, which is concerning for road safety advocates because Department of Transportation figures suggest that one in three American motorists get less than the recommended seven hours of sleep each night.
The results of a study published on Oct. 1 in the scientific journal Sleep reveal that motor vehicle accident risks increase exponentially with each hour of lost sleep. Interviews with drivers involved in 5,470 crashes investigated by the DOT suggest that drivers who sleep for six hours instead of between seven and nine are 1.3 times more likely to crash. Accidents are 2.9 times more likely with four hours of sleep according to the researchers, and motorists who get behind the wheel after sleeping for less than four hours are as impaired as a driver with a blood alcohol concentration of .12 percent.
Previous research into fatigued driving has produced equally grim results. A study published in March 2018 suggests that drivers who suffer from sleep apnea are 123 percent more likely to crash, and AAA researchers have concluded that drivers who sleep five or six hours each night are twice as likely to be involved in an accident as motorists who get seven or eight hours of sleep.
Drowsy driving accidents are often catastrophic because sleeping motorists are unable to apply their brakes or perform emergency maneuvers. A lack of evasive action could be used to establish negligence in civil lawsuits, and experienced personal injury attorneys may seek to acquire this evidence by having the vehicles involved in a collision inspected. Inspections could be useful because most modern cars are fitted with electronic devices that monitor and record driver input.