When the power goes out, the clock starts. A closed refrigerator keeps food cold for about 4 hours. A full freezer holds for about 48 hours; a half-full freezer about 24 hours.
The two numbers to remember
- 40°F (4°C): the line between safe and unsafe.
- 2 hours: discard perishable food that has been above 40°F for more than 2 hours.
Do not taste food to decide whether it is safe.
Keep or discard
| Food | Keep if | Discard if |
|---|---|---|
| Milk, yogurt, soft cheese | Still below 40°F | Above 40°F for over 2 hours |
| Raw or cooked meat, fish, poultry | Still below 40°F | Above 40°F for over 2 hours |
| Eggs | Still cold | Above 40°F for over 2 hours |
| Hard cheese, butter | Cool and intact | Moldy or above 40°F for long |
| Cooked leftovers | Still below 40°F | Above 40°F for over 2 hours |
| Fruit, vegetables | Cool and intact | Slimy, moldy, or above 40°F for long |
| Frozen food | Still has ice crystals / below 40°F | Thawed and above 40°F for over 2 hours |
When in doubt, throw it out. Food poisoning is worse than a lost meal.
Slow the warming
- Keep fridge and freezer doors closed.
- Move ice or frozen water bottles into the fridge.
- Put a thermometer in the fridge and freezer.
- Group food together in the freezer.
- Use a cooler with ice for the most perishable items.
No-cook meals
Keep a small shelf of food that does not need power:
- peanut butter, crackers, bread;
- canned fish, chicken, beans;
- dried fruit, nuts, cereal;
- shelf-stable milk;
- manual can opener.
Do not use a charcoal or gas grill indoors. Carbon monoxide can kill.
When power returns
Check the temperature before you restock. If the fridge stayed below 40°F, the food is likely safe. If not, discard perishables. Clean and sanitize the shelves.
The short version
Closed fridge: 4 hours. Full freezer: 48 hours. Above 40°F for over 2 hours: discard. When in doubt, throw it out.
For the field version, see Keep food safe in a power outage and Build a 72-hour go-bag in Fieldry.
Sources
- USDA FSIS — Keep Food Safe During a Power Outage: https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/keep-food-safe-during-power-outage
- CDC — Food Safety: https://www.cdc.gov/food-safety/
- Ready.gov — Power Outages: https://www.ready.gov/power-outages