Shift work sleep schedule: the basics from CDC/NIOSH

Night work turns the usual advice upside down. You sleep in daylight, you nap in the afternoon on purpose, and your days off pull you in the opposite direction.

The CDC's National Institute for Occupational Safety and Health (NIOSH) has a free training course on shift work for nurses. Its advice applies to anyone on nights. This guide pulls out the basics and adds clock times from our calculator library.

1. Go to bed as soon as you get home

NIOSH's first rule is blunt: "Go directly to bed when you arrive home." If you are hungry, eat something light first, such as cereal and milk, because hunger can get in the way of sleep.

Then:

• "Sleep as long as possible."
• "The more sleep you get before 2 p.m., the better rested you will be."
• Don't use the early morning for chores or errands. NIOSH calls it prime sleep time for night-shift workers.

A worked example

Say you work 7 PM to 7 AM and are in bed at 8:00 AM. With 15 minutes to fall asleep and cycles of about 90 minutes, our library gives these wake-up times:

Cycles	Sleep	Wake up
4	6 h	2:15 PM (14:15)
5	7 h 30 min	3:45 PM (15:45)

Five cycles meets the 7 or more hours CDC's table recommends for adults 18 to 60, and it still leaves a few hours before a 7 PM start. The sleep calculator does this for any shift: switch it to "going to bed now" and enter your time.

2. Make the room truly dark and quiet

NIOSH asks for a room "so dark you cannot see your hand in front of your eyes," or an eye mask. Its reasoning: "Daylight will trigger waking, and you will sleep better and longer if you sleep in darkness."

Its checklist:

• Block bedroom and bathroom windows with blackout shades or drapes.
• Seal the gaps under doors.
• Use a dim red nightlight if you must get up.
• Use earplugs or a white noise machine.
• Keep phone calls from waking you.
• Ask family and friends not to disturb you while you sleep.

3. Use light on purpose at work

NIOSH says you can be more alert if you increase your light exposure during the first half of the shift. To make sleep easier when you get home, reduce light exposure during the second half, unless you are very sleepy, when bright light may help you stay alert.

On sunglasses for the trip home, NIOSH is careful: the safest approach is to use them after a night shift "only if you have someone else to drive you home."

4. Nap before the shift

NIOSH treats napping as an important fatigue countermeasure. For nights it describes long naps before the shift, often lasting a few hours. The studies it cites include:

• Nurses and nursing aides who took a 1.5-hour nap from 3:30 to 5:00 PM were more alert in the second half of their first night shift.
• A 2.5-hour nap before a simulated night shift improved alertness compared with no nap.
• A 3-hour nap from 2 to 5 PM produced higher alertness during a later night shift.

The general advice to nap before 2 p.m. is for daytime schedules. For night workers, the late-afternoon nap is the point.

With the nap calculator: lie down at 3:20 PM, allow 10 minutes to fall asleep, and the full-cycle alarm is 5:00 PM. That leaves time to eat and commute. The calculator will flag the nap as "after 2 PM." On a night-shift day, you can ignore that flag.

NIOSH also says to avoid staying awake for long stretches before your first night shift or after your last one. That raises the risk of accidents and of long-term sleep loss.

5. Days off: the compromise schedule

Flipping fully back to days and then to nights again is hard. NIOSH describes a compromise suggested by scientists to keep sleep times more consistent:

• Work nights: sleep as soon as you get home (for example, 8 a.m.) and as long as you can.
• Days off: stay up until the middle of the night (3 to 4 a.m.) and sleep until noon or 1 p.m.

The two sleep windows overlap in the morning hours, so your body clock does not swing a full 12 hours each week. And whenever you can, NIOSH says, sleep, including naps.

A sample week

Here is the NIOSH guidance laid out for someone working three 7 PM–7 AM shifts:

Day	Sleep	Nap
Before the first night	Usual night's sleep	3:30–5:00 PM
Work nights	8:00 AM to about 3:45 PM	If possible, before returning to work
Days off	About 3:00–4:00 AM to noon or 1:00 PM	If needed

Treat this as a starting point to adapt, not a prescription.

When to talk to a doctor

Shift work makes sleep harder for almost everyone. Still, CDC says to talk to your healthcare provider if you regularly have problems sleeping. It lists trouble falling asleep, repeatedly waking up during the night and feeling sleepy even after enough sleep as signs of poor sleep quality. If you nod off while driving or at work, don't wait. Talk to a doctor.