When you lose electricity — whether it’s from flooding, high winds or another disaster — food safety can be an issue. The longer the power is out, the more likely your food is to spoil, but knowing how to protect your food and determine if it’s safe to eat will help minimize the risk of foodborne illness.

Meat, eggs and dairy should be kept at or below 40 degrees Fahrenheit, and frozen food should maintain a temperature at or below 0 degrees F. If you lose power, the refrigerator will keep food safe for about four hours if the door remains closed.

A full freezer will maintain its temperature for approximately two days — if the freezer is half full, food will stay frozen for about 24 hours. If you don’t have a full freezer, place items close together to help the food stay cold longer.

If you expect you could lose power, the U.S. Department of Agriculture (USDA) suggests obtaining dry or block ice ahead of time to keep food at a safe temperature. Fifty pounds of dry ice will keep an 18-cubic foot freezer cold for two days.

Coolers are another option for keeping food safe and cold if the power stays out for more than four hours. Stock the freezer with frozen gel packs that can be transferred to coolers in the event you lose power.

It’s a good idea to keep food thermometers in the refrigerator and freezer at all times so you know if food is safe to eat. Generally, if the freezer temperature stays at 40 degrees F or below, the food is safe and can be refrozen, according to the USDA.

Also, keep food on hand that doesn’t require refrigeration and can be eaten cold or heated without an oven or microwave. Canned goods, bottled water and other nonperishable items should be part of your emergency food supply. If you have pets or small children, also stock up on pet food and ready-to-use baby formula.

To learn more about food safety during an emergency, check out the USDA’s emergency preparedness fact sheet.

Laura Moss writes about a variety of topics with a focus on animals, science, language and culture. But she mostly writes about cats.

Practice food safety when the power goes out
Simple food safety tips for power outages can help protect your food and determine if it’s safe to eat while minimizing the risk of foodborne illness.