Is Your Home Prepared for a Power Outage?

Start with an inventory of what depends on electricity

Ready.gov's first recommendation is to take an inventory of the items you need that rely on electricity, and then plan batteries and other alternative power sources for them. For most homes that list is longer than expected: the refrigerator and freezer, a well pump if you have one, sump pumps, furnace blowers (even on gas furnaces), garage door openers, cordless phones, Wi-Fi routers, and any medical equipment.

Go room by room and sort each item into three groups: must keep running (medical devices, refrigerated medicine), would be nice to keep running (refrigerator, a few lights, phone charging), and can go without. That list becomes the basis for every other decision in this guide, including whether a generator makes sense for you.

• Have flashlights for every household member (Ready.gov).
• Keep a portable charger or power bank for phones (Ready.gov).
• Find out whether your home phone works in an outage and how long its battery backup lasts (Ready.gov).
• Disconnect appliances and electronics during the outage; power can return with surges or spikes that cause damage (Ready.gov).

Medical needs come first

If anyone in your household uses a powered medical device or a medication that must be refrigerated, Ready.gov recommends talking with a medical provider about a power outage plan, including how long the medication can be stored at higher temperatures and specific guidance for medications that are critical for life.

Ready.gov also advises that if the power is out for more than a day, you should discard any medication that should be refrigerated unless the drug's label says otherwise, and consult your doctor or pharmacist for a new supply. That makes a week-long outage a medication-planning problem as much as a comfort problem. Write the plan down and keep it with your emergency kit.

Food safety: the 4-hour and 48-hour rules

Keep refrigerator and freezer doors closed. According to the CDC, a refrigerator keeps food safe for about 4 hours without power, a full freezer for about 48 hours, and a half-full freezer for about 24 hours.

The CDC advises throwing out perishable refrigerator food (meat, poultry, fish, eggs and leftovers) once the power has been off for 4 hours or more, and discarding freezer food that has thawed. Ready.gov adds a temperature test: throw out food that has been at 40 degrees or higher for two hours or more, or that has an unusual odor, color or texture. A simple appliance thermometer in the fridge and freezer takes the guesswork out of this.

• Keep a several-day supply of non-perishable food that needs no refrigeration (Ready.gov).
• Use coolers with ice if needed, and monitor temperatures with a thermometer (Ready.gov).
• Never taste food to decide whether it is safe. When in doubt, throw it out (CDC, Ready.gov).

Water when the power is out

The CDC notes that water purification systems may not work fully during an outage, and recommends using bottled, boiled or treated water for drinking, cooking and hygiene, following your health department's guidance. If your home relies on an electric well pump, an outage can mean no running water at all.

The CDC recommends storing at least 1 gallon of water per person per day for at least 3 days, and a 2-week supply if possible. Our emergency water planning guide includes a worked example for different household sizes.

Heat, cold and carbon monoxide

Temperature is often what turns a long outage dangerous. The CDC warns that fans alone won't prevent heat-related illness and recommends going to an air-conditioned shelter, mall or library if your home has no air conditioning. In cold weather, the CDC says a body temperature below 95°F is a medical emergency, and suggests keeping at least one heat source such as extra blankets or a properly vented fireplace. Ready.gov recommends going to a community location with power if heat or cold is extreme, and checking with local officials about heating and cooling locations.

Never use a gas stove or oven to heat your home. Ready.gov notes this increases the risk of carbon monoxide poisoning and of fires and burns. Generators, camp stoves and charcoal grills should only be used outdoors and at least 20 feet from windows (Ready.gov). Install carbon monoxide detectors with battery backup in central locations on every level of the home (Ready.gov).

So, could your home manage a week?

A useful test is to walk through a seven-day outage on paper. Day one is mostly about keeping doors closed and phones charged. By day two, refrigerated food and refrigerated medication decisions are due. Over the following days, water supply, temperature control and communication become the limiting factors.

If your answers to the questions below are mostly yes, your home is in good shape. If several are no, those are your weak points, and they are usually inexpensive to fix ahead of time.

• Do you have a written plan for every powered medical device and refrigerated medicine?
• Do you have at least 3 days, and ideally 2 weeks, of stored water at 1 gallon per person per day?
• Do you have non-perishable food that needs no refrigeration?
• Do you have flashlights for each person, spare batteries and a way to charge phones?
• Do you have working, battery-backed carbon monoxide alarms on every level?
• Do you know where the nearest heating or cooling location would be?
• If you own a generator, do you know how to run it safely outdoors?