The 72-Hour Blackout Checklist: What to Do When the Power Goes Out

The 72-Hour Blackout Checklist: What to Do When the Power Goes Out

Most power outages end in an hour or two. The ones that matter are the ones that stretch into a second or third day, when the freezer starts to warm, phones start to die, and the house gets too cold or too hot to sit in comfortably. This is the calm, in-order version of what to do, built around the same idea that runs through every emergency: handle safety first, then temperature, then food, then everything else.

What should you do in the first 30 minutes?

Confirm what you're actually dealing with before you do anything else. Check a neighbor's house or a utility outage map to see if it's just your breaker or the whole block. If it's your panel, that's a five-minute fix, not a three-day event.

Then work through this short list:

1. Unplug sensitive electronics (computers, TVs, routers) so a power surge doesn't damage them when service returns. Leave one lamp plugged in as a signal light.
2. Keep the fridge and freezer doors shut and note the time. You're now on a food-safety clock, covered below.
3. Find your flashlights or headlamps before it gets dark, not after. Searching a dark house for a flashlight is how people get hurt on stairs.
4. Check on anyone in the home who relies on powered medical equipment. This is the one item that can turn a mild inconvenience into a genuine emergency, and it's worth having a backup plan for well before a storm is forecast.

How long is food actually safe without power?

Longer than most people assume, if the doors stay shut. The U.S. government's food safety guidance is specific: a full freezer holds a safe temperature for about 48 hours, or 24 hours if it's only half full, as long as you keep the door closed. A closed refrigerator keeps food safely cold for about 4 hours.

A few practical notes that make the difference:

• Group freezer items together and fill empty space with bags of water or ice. A full freezer stays cold far longer than a sparse one.
• Keep an appliance thermometer in the fridge if you have one. Discard anything that's been above 40°F (4°C) for more than two hours.
• Never taste food to check if it's safe. You can't tell by smell or appearance alone whether bacteria have made it dangerous.
• When in doubt, throw it out, especially meat, dairy, eggs, and leftovers. It's a frustrating loss, not a health risk worth taking.

How do you get light without starting a fire?

Reach for a headlamp or flashlight before a candle. Hands-free light matters when you're doing anything else in the dark, like checking on kids or finding the water shutoff.

If candles are your only option, keep them on a stable, non-flammable surface, away from curtains and paper, and never leave one burning in an empty room or while you sleep. A crank or solar lantern is a safer choice for a multi-day outage, and glow sticks are a good, zero-risk option for a kid's room.

Can you run a generator inside, or in the garage?

No, never, under any circumstance. This is the single most dangerous mistake people make in an extended blackout. Carbon monoxide from a generator is invisible and odorless, and running one in a garage, basement, or near an open window can kill people inside the house within hours.

The CDC's guidance is specific: run a generator outdoors, at least 20 feet from your home and away from any doors, windows, or vents. Testing has shown that even 15 feet isn't a safe margin. Point the exhaust away from the house, and install a battery-powered carbon monoxide detector if you own a generator. The same rule applies to charcoal grills and camp stoves. They're for outdoor cooking, never for heating an indoor space.

How do you stay warm or cool without power?

In cold weather, close off rooms you're not using and gather everyone into one smaller space to share body heat. Layer clothing rather than relying on a single heavy layer, and use blankets and sleeping bags rated for indoor temperatures well below what feels comfortable. Only use fuel-burning heaters that are specifically rated and vented for indoor use, and never as a first resort. Heating one room well, safely, is worth learning properly rather than improvising under pressure.

In hot weather, close blinds during the day to block heat gain, and open windows at night if it's safe to do so. Drink water steadily rather than in large amounts at once, and check on elderly relatives or neighbors, since heat stress builds quietly and is easy to miss in someone else.

How do you keep a phone charged for three days?

Charge everything before a storm is even forecast, and switch to low-power mode the moment the outage starts. A power bank or a car charger (used with the car outside, never idling in a closed garage) will carry you through most outages. A small solar charger is worth having if outages are common where you live.

Save your phone for what actually matters: checking on people and reading official alerts. A battery or hand-crank radio is a better source for ongoing updates, since it doesn't drain a battery you may need later. Keep a paper copy of important phone numbers too. If your phone dies, so does your contact list.

When does an outage become a real emergency?

Usually when it overlaps with something else: a medical device that needs power, extreme outdoor temperatures, a well pump that means no running water, or a sump pump failure that risks flooding a basement. If any of those apply to your household, decide your backup plan (a relative's house, a hotel, a community warming or cooling center) before you need it, not while you're standing in a cold, dark kitchen.

Past the first day, treat it the same way you'd treat any longer disruption. Our guide to the first 72 hours after a collapse walks through the same decision points in more depth: when to shelter in place, when to leave, and how to ration what you have.

What should already be in the house before this happens?

A short list, built once, used for years:

• Flashlights or headlamps, with spare batteries
• A battery or hand-crank radio
• At least three days of stored water per person (here's exactly how much and how to store it)
• Food that needs no cooking, plus a manual can opener
• A charged power bank
• A basic first aid kit that goes beyond drugstore bandages
• Small bills in cash, since card readers need power too

Key takeaways

• Freezers hold safe temperatures for about 48 hours full, 24 hours half full, if the door stays shut. Fridges last about 4 hours.
• Never run a generator, grill, or camp stove indoors or in a garage. Keep generators at least 20 feet from windows and doors.
• Reach for a headlamp before a candle, and never leave a flame unattended.
• Save phone battery for essentials and lean on a battery or hand-crank radio for updates.
• Decide your backup plan for medical needs or extreme temperatures before the power goes out, not during.

If you want the one-page version to print and keep on the fridge, the free 72-Hour Emergency Checklist is here: https://afterdoomsday.com/kit. For the full, calm, chapter-by-chapter guide to water, food, medicine, and getting through the harder stretches, After Doomsday — The Survival Bible for the End of the World by Ryan T. Hale is available on Amazon.

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