Quick answer
- Keep the fridge and freezer closed. A closed fridge keeps food safe for about 4 hours. A full freezer lasts about 48 hours, a half-full one about 24.
- Run generators outdoors only, at least 20 feet from windows, doors and vents. The CDC says never run one in a home or garage, even with doors and windows open.
- Unplug electronics so a power surge can’t damage them when power returns.
- Use flashlights, not candles. Stay at least 35 feet from downed power lines.
- Leave if your home gets too hot or too cold, or if a medical device needs power.
This guide covers a power outage from start to finish. For a short version that also covers apartment fires, heat waves and water outages, see Urban Survival: How to Handle City Emergencies at Home.
Before an outage
Most of the work happens before the lights go out. Do these things now, while stores are open and you have power.
Make a list of what needs power
Walk through your home and write down everything that runs on electricity. Ready.gov suggests making a backup plan for each item that matters.
- Fridge and freezer
- Medical devices and refrigerated medicine
- Phones and the internet router
- Heating or cooling
- Well pump, sump pump, garage door and electric stove
Check if your home phone works without power, and for how long. Ready.gov lists this as a step many people skip.
Stock basic supplies
Ready.gov’s basic kit calls for 1 gallon of water per person per day for several days. The Red Cross suggests a 2-week supply of food and water for staying at home. Outages can also make tap water unsafe.
- Flashlight and spare batteries for each person
- Battery-powered or hand-crank radio
- Food you can eat without cooking
- Manual can opener
- Phone chargers and a charged power bank
- Hand sanitizer with at least 60% alcohol
- Fridge and freezer thermometers
For a full list, see 10 Must-Have Items for Your Basic Survival Kit.
Protect your home
- Install carbon monoxide (CO) alarms with battery backup on every level of your home. A plug-in alarm with no battery will not work in an outage.
- Put battery-backup smoke alarms on every floor, inside and outside sleeping areas. The Red Cross says to test them monthly.
- Use surge protectors on computers, TVs and other electronics.
- Keep your car’s gas tank at least half full, as the Red Cross advises.
- Learn how to open your garage door by hand.
Plan for medical needs
A power outage can be life-threatening if someone relies on powered medical equipment. Ready.gov says to ask your medical provider two questions:
- How do I keep this device running during an outage?
- How long can my medicine stay safe at a higher temperature?
Keep spare batteries charged, and pick a place with power you can go to. Our guide to emergency preparedness for people with disabilities covers backup power, utility priority lists and more.
During an outage
First 10 minutes
- Check if your neighbors have power. If they do, check your breaker panel.
- Report the outage to your power company.
- Get out flashlights. Avoid candles, which the CDC and Red Cross warn are a fire risk.
- Unplug appliances and electronics. Power can come back with surges or spikes.
- Leave one lamp switched on, so you know when power is back.
- Turn on your battery or hand-crank radio for news.
Keep food safe
The USDA, through FoodSafety.gov, gives these times for food kept with the doors closed:
| Appliance | Safe time without power |
|---|---|
| Refrigerator | Up to 4 hours |
| Full freezer | About 48 hours |
| Half-full freezer | About 24 hours |
A safe fridge is 40°F (4°C) or below. A safe freezer is 0°F (-18°C) or below. Open them only when you must.
If the outage will last longer than 4 hours:
- Move milk, meat, fish, eggs and leftovers to a cooler packed with ice or frozen gel packs.
- Keep enough ice in the cooler to hold food at 40°F (4°C) or below. Add more as it melts.
- For a long outage, buy block ice or dry ice. The USDA says 50 pounds of dry ice should keep an 18-cubic-foot freezer cold for 2 days.
- Never touch dry ice with bare hands, and don’t let it touch food.
For cooking safely without power, see Emergency Cooking: How to Make Meals Without Power.
Use a generator safely
Generator exhaust contains carbon monoxide. You can’t see it or smell it, and it can kill. Follow the CDC and Red Cross rules every time.
- Run the generator outdoors only. Never use it in your home, garage, basement or crawlspace.
- Keep it at least 20 feet from windows, doors and vents, even if they are closed.
- Use an extension cord longer than 20 feet so the generator can stay far from the house.
- Use a heavy-duty, outdoor-rated cord. The Red Cross says it should be rated for at least the total load you plug in.
- Check the cord for cuts. Make sure the plug has all three prongs.
- Keep the generator dry. Run it on a dry surface under an open, canopy-like cover.
- Turn it off and let it cool before you refuel. Spilled gas on hot parts can catch fire.
- Never plug a generator into a wall outlet. This “backfeeding” can electrocute utility workers and neighbors.
- To power your home’s wiring, have an electrician install a transfer switch.
The Red Cross warns that opening windows or running fans does not stop CO buildup. Run a battery-powered or battery-backup CO alarm whenever a generator is on.
Know the signs of carbon monoxide poisoning
The CDC lists these common symptoms:
- Headache
- Dizziness
- Weakness
- Upset stomach or vomiting
- Chest pain
- Confusion
The CDC says people who are asleep or drunk can die before they feel any symptoms. If a CO alarm sounds or someone feels sick, get everyone outside to fresh air. Then call 911 or Poison Control at 1-800-222-1222.
Other CO sources are just as dangerous. The CDC says never use a gas stove or oven to heat your home.
It also says never use a charcoal grill, camp stove or lantern indoors. Never run a car in an attached garage, even with the door open.
Stay cool in hot weather
The CDC advises three steps in a summer outage:
- Go to a place with air conditioning.
- Drink plenty of fluids.
- Take a cool bath or use a wet cloth to cool down.
The CDC also says not to rely on fans alone to keep cool. Signs of heat stroke include a body temperature of 103°F or higher, confusion and passing out.
The CDC says heat stroke is a medical emergency, so call 911 right away. Move the person somewhere cooler and cool them with wet cloths or a cool bath. Do not give them anything to drink.
Stay warm in cold weather
The Red Cross gives these tips for a winter outage:
- Dress in loose layers. Add a hat and mittens.
- Drink warm fluids. Avoid caffeine and alcohol.
- Check on older neighbors and families with babies.
- If your home gets too cold, go to a friend’s home, a library or a warming center.
If you use a space heater, the Red Cross says to keep anything that can burn at least 3 feet (1 m) away. The CDC says to get medical help right away if a person’s temperature drops below 95°F (35°C).
Watch out for medicine
Ready.gov says to throw out refrigerated medicine if the power is out for more than a day. The exception is when the label says otherwise. Call your doctor or pharmacist for a new supply as soon as you can.
If a life depends on the medicine, such as insulin, do not just throw it out. The CDC says to keep using it only until a new supply is available.
When to leave home
Ready.gov and the Red Cross say to go somewhere else if:
- Your home is too hot or too cold to stay safe.
- Someone needs power for a medical device.
- Local officials open warming or cooling centers and tell you to go.
Check local news or your county’s alert system to find open centers.
Downed power lines
Storms that cut power often bring down lines too. Treat every fallen line as live.
- The Red Cross says to stay at least 35 feet from downed lines and anything touching them. Call 911.
- The CDC says never touch a fallen power line.
- Never drive through standing water if a downed line is in it.
- Report lines to your power company, and watch for lines hanging overhead.
- If someone gets an electric shock, call 911. MedlinePlus says not to touch them with bare hands if they still touch the power source.
- Do not try to rescue anyone near a live power line. Wait for the power to be cut.
After the power comes back
- Plug appliances back in one at a time.
- If breakers tripped, the Red Cross says to have an electrician check them before you reset them.
- If you turned off the gas, only a qualified professional should turn it back on.
- Don’t use any electrical equipment that was underwater. Have an electrical inspector check it first.
- Check the fridge and freezer thermometers before you eat anything.
Sort your food
Use these rules from Ready.gov, the CDC and FoodSafety.gov:
- Throw out food that was at 40°F (4°C) or higher for 2 hours or more.
- Throw out refrigerated meat, poultry, fish, eggs, milk and leftovers if the power was off more than 4 hours.
- Throw out food with an unusual smell, color or texture.
- You can refreeze freezer food if it still has ice crystals or is at 40°F (4°C) or below.
- Never taste food to see if it is safe.
When in doubt, throw it out.
Check your water
If officials say your water may be unsafe, use bottled, boiled or treated water. That includes water for drinking, cooking, brushing teeth and baby formula.
Common mistakes
- Opening the fridge to check on food. Each opening lets cold air out. Use a thermometer instead.
- Running a generator in the garage “with the door open.” The CDC says never use one in a home or garage, even with doors open.
- Heating the house with a gas oven. This can cause CO poisoning.
- Using candles for light. Flashlights and battery lanterns are safer.
- Plugging a generator into a wall outlet. This puts power workers and neighbors at risk.
- Tasting food to see if it is still good. FoodSafety.gov says never taste food to judge if it is safe.
Power outage checklist
Get ready now
When the power goes out
When the power comes back
Related guides
Sources
- Power Outages (archived copy) — Ready.gov
- Power Outage Tips — Ready.gov
- Build a Kit — Ready.gov
- What to Do to Protect Yourself During a Power Outage — CDC
- Carbon Monoxide (CO) Poisoning Basics — CDC
- Prevent Heat-Related Illnesses During a Power Outage — CDC
- Heat-Related Illnesses (fact sheet) — CDC
- Refrigerated Drugs — CDC
- Electrical injury — MedlinePlus, U.S. National Library of Medicine
- Carbon Monoxide (CO) — Poison Help, Health Resources and Services Administration
- Three Ways to Keep Food Safe When You Lose Power — FoodSafety.gov (USDA)
- Avoid Foodborne Illness During Temporary Power Outages — FoodSafety.gov (USDA)
- Power Outage Safety — American Red Cross
- Generator Safety — American Red Cross
- Winter Storm Safety — American Red Cross