Two hours of sleep? You’re too impaired to drive, experts say

Washington – If you’re going to drive, you need more than two hours of sleep.

That’s the determination reached by a National Sleep Foundation expert panel.

Sleep, medicine and transportation scientists met to define the threshold for when drivers are too tired to drive, according to a press release. The definition was announced during the foundation’s Drowsy Driving Prevention Week (Nov. 1-6).

People need various amounts of sleep, and stimulants such as caffeine might help them feel awake, one expert noted. But people are impaired when they sleep less than two hours a day – and for some people, even four hours of sleep leaves them too fatigued to drive, Charles A. Czeisler, chair of NSF’s Drowsy Driving Consensus Workgroup, said in the release. The two-hour benchmark should be a “red-flag warning” for people, Czeisler said.