MICHELE NORRIS, host:
From NPR News, this is ALL THINGS CONSIDERED. I'm Michele Norris.
There are some job requirements that seem so obvious you hardly need to point them out. For example, it doesn't say in the NPR manual that we're not supposed to fall asleep when hosting a live news program.
So it's not surprising people were outraged when they found out that air traffic controllers fall asleep on the job. But working the overnight shift is tough, as NPR's Joe Palca explains.
JOE PALCA: Humans are not nocturnal, but modern society demands some people work at night. So is there anything you can do to be certain that people will stay awake during the graveyard shift?
Mr. TORBJORN AKERSTEDT (Sleep Researcher, Karolinska Institute): I usually say no when I get that question.
PALCA: Torbjorn Akerstedt is a sleep researcher at the Karolinska Institute in Stockholm.
Mr. AKERSTEDT: Night work is un-physiological. You can never make it as good as day work.
PALCA: What Akerstedt means by un-physiological is our bodies have an internal clock that's designed to keep us alert during the day and asleep at night. And that clock is set by the time the sun rises and sets. So any kind of night work is tough, but...
Mr. AKERSTEDT: There are several varieties of night work that are worse than other types.
PALCA: Such as?
Mr. AKERSTEDT: Well, if you have very short rest periods between shifts.
PALCA: That's because getting enough sleep before a night shift starts is important for staying up. But there's a problem.
Mr. TOM ROTH (Sleep Researcher, Henry Ford Hospital): If I give you 12 hours of sleep by day, you're still going to be impaired at 2:00 in the morning because your clock doesn't adjust.
PALCA: Tom Roth is a sleep researcher at the Henry Ford Hospital in Detroit. So what can you do at two in the morning when your internal clock is telling you to sleep? Roth says a nap during your shift might help.
But Secretary of Transportation Ray LaHood has apparently ruled that out for air traffic controllers. Here's LaHood on Fox News Sunday.
Secretary RAY LaHOOD (Department of Transportation): On my watch, controllers will not be paid to take naps.
PALCA: LaHood says the government's plan is to give controllers an extra hour off between shifts. Tom Roth is not convinced that's the way to go.
Mr. ROTH: I would rather see that hour of extra sleep at two to four in the morning, when the person is really impaired in that tower.
PALCA: Roth says anyone who's experienced jet lag knows what it feels like when your body is tugging at you to fall asleep. The difference is when you fly halfway around the globe, the light changes with you, and the light of the local daytime helps you shift your internal clock.
You can shift your internal clock artificially, with bright lights at night and dark curtains during the day, but it's tough and hard to maintain. It's also true that some people can handle jet lag or night shift work more easily than others.
Mr. MAURICE OHAYON (Sleep Researcher, Stanford University): You have people that are short sleepers, people that are long sleeper.
PALCA: Maurice Ohayon is a sleep researcher at Stanford University. Not only do people vary on the amount of sleep they need, there are also differences in when they need their sleep. Larks tend to like to go to sleep early, and get up early. For night owls, it's the opposite.
But Ohayon says everyone will experience times when they get sleepy in the middle of the night.
Mr. OHAYON: Here is the biggest problem. We know that sleepiness is something that is taking you by surprise. You don't know when are passing from sleepiness to sleep.
PALCA: In other words, if you become excessively sleepy, you can fall asleep and not realize it.
Mr. OHAYON: You are always at risk to have a big period of excessive sleepiness. The sleep can come at any moment. The danger is there.
PALCA: So if you're always at risk for this, why don't we see more accidents or near misses in people who are doing critical jobs in the middle of the night?
Mr. OHAYON: We are lucky.
(Soundbite of laughter)
PALCA: Not a particularly comforting thought, but it does mean it will take more than threats from angry politicians to keep people awake and vigilant in the middle of the night.
Joe Palca, NPR News, Washington.
NORRIS: And NPR wants to hear from you. Do you work the night shift? How do you cope? Let us know on the NPR Facebook page.