How to sleep after a night shift: the drive home, the dark room, the nap and the days off

Night workers usually get less sleep, and lower-quality sleep, than people who sleep at night. That is the starting point of the NIOSH Training for Nurses on Shift Work and Long Work Hours, a free course from the U.S. National Institute for Occupational Safety and Health. It was written for nurses, but its sleep advice does not depend on the job. Unless another source is named, everything below comes from it.

The day after a night shift, in order

NIOSH’s example has the worker home at 8 a.m. Move the times to fit your own shift.

Each row is explained below with its source. The light rows come from the course’s night-shift light page, which calls the body-clock benefit for permanent night workers theoretical; bright light early in the shift is mainly about staying alert.

Make the bedroom dark enough that you can’t see your hand

NIOSH sets the bar for a daytime bedroom at a room “so dark you cannot see your hand in front of your eyes” (sleep after a night shift). Closing the curtains rarely gets there. The bedroom light checklist:

• Windows: room-darkening shades or heavy, lined drapes, adjusted so no light leaks around the edges. Blinds let too much through.
• Doors and hallways: turn off hall lights or put a draft stopper under the door. If light still gets in, wear an eye mask for the whole sleep.
• Inside the room: remove or cover anything that glows, such as a lit clock, a phone or a TV.
• The bathroom trip: keep the path dark and clear, with a dim red nightlight if you need one.

Noise is the other half. NIOSH suggests earplugs, a fan or a white-noise machine, asking the household to keep out of the bedroom and keep the noise down, and setting the phone to Do Not Disturb with chosen contacts allowed through for emergencies. Keep the room cool, and turn the clock face away so you are not checking the time.

Caffeine belongs at the start of the shift

NIOSH gives caffeine’s half-life as 5 to 6 hours, longer in some people, and suggests that night workers who use it have it at the start of the shift and stop several hours before the end. The arithmetic explains why: a coffee at 3 a.m. still leaves about half its caffeine in your system when you lie down at 8 or 9.

The same page covers the rest of the run-up to sleep: dim lights for an hour or two before bed, no heavy or spicy meals in the 2 to 3 hours before, not too much to drink, and any alcohol several hours ahead, because it can wake you early.

The drive home is the riskiest part of the morning

NIOSH notes that many nurses feel excessively sleepy after night shifts and have a higher risk of crashing on the way home. It mentions a brief nap at work before driving as something that might help, and says plainly that this has not been tested.

Sunglasses are a trade-off. Blocking bright morning light on the way home may help you sleep longer afterwards, but researchers worry that it also takes away light’s alerting effect from a driver who is already very sleepy. NIOSH’s safest approach is to wear dark sunglasses after a night shift only if someone else is driving, put them on before you step outside, and keep them on until you are back in a dark room.

The nap before the next night

NIOSH recommends napping before you go back to work if you can: it adds to your total sleep and helps you stay alert through the night. This prophylactic nap is usually long, a few hours, enough to reach deeper sleep and ease the sleep pressure of the night ahead. The studies NIOSH cites:

In 2007, the American Academy of Sleep Medicine’s practice parameters rated planned napping before or during the night shift a “standard”, its highest-certainty category, for improving night workers’ alertness and performance.

Long naps have a cost: grogginess on waking, called sleep inertia. Waking after about 20 or about 90 minutes tends to leave you less groggy than waking after about an hour, in deep sleep, and that grogginess may clear within 15 to 30 minutes. It lasts longer when you are short of sleep, so leave time before you drive or do anything where a mistake matters.

Days off: keep part of the window

Switching all the way back to night sleep on every day off keeps your body clock in something close to permanent jet lag. The compromise NIOSH describes: on days off, stay up until 3 or 4 a.m. and sleep until noon or 1 p.m. That way a block such as 8 a.m. to noon is sleep time on work days and days off alike.

The same page warns against the opposite shortcut: staying awake all day before the first night of a run, or after the last one. You end up awake for too many hours, which raises the risk of accidents and, over time, of chronic sleep loss. The course does not cover rotating schedules in detail; rotating workers who struggle to adjust are pointed to a sleep specialist.

When it’s more than a bad week

Persistent sleep problems should not be ignored, NIOSH says, and a sleep disorder such as sleep apnea or insomnia can make enough sleep impossible until it is treated. The American Academy of Sleep Medicine’s page on shift work disorder draws a similar line: a new shift is hard for many people at first, but if after several weeks you still have trouble falling or staying asleep, or feel tired even after 7 to 8 hours, you may have shift work disorder. That is a conversation for your doctor or a sleep specialist, and so is any sleep aid or supplement.

Where AfterShift fits

AfterShift is an iPhone app for people on night, rotating and on-call schedules. It is an informational tracker: it shows what your sleep is doing around your shifts, but it does not diagnose or treat anything, and none of the advice above depends on it. Where it meets that advice:

• It reads your sleep and labels it. AfterShift reads sleep from Apple Health (it never writes or shares that data) and tells you where each sleep fell: after a night shift, before one, between shifts or on a recovery day.
• It shows whether bedroom changes worked. For each sleep you see time asleep against time in bed, sleep efficiency, the sleep midpoint and whether you slept inside the planned window. If new blackout shades help, that is where it shows.
• It plans the next window. Add your next shift and the Today tab shows a planned sleep window, flags one shorter than six hours, and suggests a short 20 to 30 minute nap when recovery time is tight. If you tell it you can’t nap, it stops suggesting nap windows. The long pre-shift naps in the NIOSH table are yours to plan; Log Nap records them and asks how the nap went, including whether you woke up groggy.
• It times caffeine against your sleep, not the clock. Setup asks for your one-way commute and your caffeine sensitivity, which sets a cutoff of 4, 6 or 8 hours before sleep. Caffeine you log from the Today tab is marked good, borderline or late over the last 14 days.
• The Coach tab has short explainers on light, naps, caffeine timing and the daytime sleep environment.

The Shift Recovery Score is built from sleep length, continuity and the timing of your next shift, and like everything else on the screen it is information, not a verdict. There is no account, and your data stays on your device; the privacy page has the details, and the design post explains why the app treats daytime sleep as normal.

The advice itself is free and older than any app: a dark room, early caffeine, a nap before the next night, and a doctor if the sleep still won’t come.