Ever had one of those days when you leave work feeling exhausted, and all you want to do is get home and crash on the couch? Unfortunately, if you are exhausted and drive home, you may have an altogether different type of crash.

Being exhausted or fatigued makes you three times more likely to have a car accident, according to the National Safety Council (NSC). The NSC gives a few comparisons of how lack of sleep can affect your mental ability to drive: Losing two hours is as bad for your driving as having three beers; being awake for 20 hours and driving is as dangerous as driving while drunk.

There are many reasons you may be fatigued. Perhaps your new baby kept you up all night. Maybe you have been putting in long shifts at work to cover someone who is off sick. Perhaps you are unable to sleep worrying about how long your business will last in the current climate, or how you will pay those outstanding mortgage payments.

You could be exhausted for good reasons too: You could have been up late talking with friends, or driving through the night to get back after a great weekend away.

Now think about all the other people who drive when they are fatigued, whom you could encounter on the road such as truck drivers delivering goods through the night, night workers on their way home in the morning or teenagers who stay up until all hours gaming.

One thing is clear: Driving while fatigued, whatever the reason, is dangerous.