Labor Day holiday dangerous for drivers: How many will die?

(CBS) Planning a road trip this Labor Day? Be careful. The holiday weekend is one of the busiest times of the year for U.S. roads - and one of the deadliest.

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This year the weekend will see 400 traffic fatalities and 38,800 injuries serious enough to require medical attention, the National Safety Council projects. For the past six years, the Labor Day weekend has averaged almost 15 percent more traffic fatalities than similar four-day periods that don't involve a holiday.

What will cause all those fatal accidents? Speeding is perennially among the top causes. So is drunk driving. That's why the National Impaired Driving Crackdown, which started August 19 and runs through September 5, was put into place.

Fatigue is another big factor, Peter Kissinger, president and CEO of the AAA Foundation for Traffic Safety, told CBS News. He called on motorists to get enough sleep before hitting the road this Labor Day - and not to hesitate to pull off the road for a rest if fatigue starts to set in.

What else can motorists do to stay safe on the road this Labor Day? In addition to sticking below the speed limit, wearing your seatbelt, and not driving while impaired or fatigued, Kissinger said it's important to have a realistic sense of your own abilities behind the wheel.

"Most people act as if they were born in Lake Wobegone and are all 'above-average' drivers," he said, alluding to the familiar line from "A Prairie Home Companion," Garrison Keillor's radio program. "Honestly, look in the mirror and make sure you are not part of the problem."

The National Highway Safety Administration has more on driving safety.