No Power? No Problem! Food Safety during a Power Outage

Adair P. Hoover,
Home & Garden Information Center

February is prime time for power outages in South Carolina. Ice, snow and heavy winds can arise and create perfect conditions for power outages. Losing power is a hassle and one of the things we need to immediately consider is the safety of stored food.

One of the fundamentals of food safety is temperature. For many perishable foods, freezing and refrigeration prolong the length of time that they will retain acceptable quality and safety. We rely on our refrigerators and freezers for safe storage and when power is lost we are reminded of how much we depend on them.

When power outages occur it is best to have a food safety plan in place. Being proactive can help you reduce waste and give you confidence when deciding whether foods are safe to eat. An appliance thermometer in your refrigerator and freezer is a great way to be sure that foods remain at safe temperatures. Keep it in the refrigerator and freezer at all times to verify that food is being stored at safe temperatures (34 to 40 °F for the refrigerator; 0 °F or below for the freezer).

In preparation for a power outage:

  • Have an appliance thermometer.
  • Know where you can get dry ice.
  • Always have a few days’ supply of ready-to-eat, shelf stable food on hand.
  • Have several freezer packs available or milk containers filled with water and frozen.

When you lose power:

4 hours or less:

If the power is out for 4 hours or less, refrigerated and frozen foods should be safe as long as the refrigerator or freezer doors remain closed. Every time you open them, cold air escapes, causing the foods inside to warm. When power returns, check temperatures and discard any perishable food that has been above 40 °F for two hours or more and any food that has an unusual odor, color or texture.

More than 6 hours:

If a power outage lasts for more than 6 hours some safety precautions should be taken.

  • Leave the Freezer Door Closed. A full freezer should keep food safe about two days; a half-full freezer, about a day. If the freezer is not full, group packages together quickly. Arrange meat and poultry together on one side or on separate trays so their juices will not cause cross contamination should thawing occur. Then avoid opening the freezer door to prevent the cold air from escaping.
  • Add bags of ice or dry ice to the freezer if it appears the power will be off for an extended time. Use three pounds of dry ice per cubic foot of freezer space. Dry ice registers -216 °F, so rubber gloves or tongs must be used when handling it. Wrap the ice in brown paper for longer storage, and separate it with a piece of cardboard from direct food contact. If the freezer is partially empty fill with crumpled newspaper to cut down on air currents, which cause the dry ice to dissipate. Provide adequate ventilation for carbon dioxide in areas where dry ice is used. Do not cover air vent openings of freezer.
  • Refrigerator items should be transferred to an insulated cooler filled with ice or frozen gel packs. Keep a thermometer in the cooler to be sure the food stays at 40 °F or below.

For more detailed information on food safety during a power outage see HGIC 3760, Food Safety in Power Outages and HGIC 3780, Food Safety in Freezer Failure.

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This information is supplied with the understanding that no discrimination is intended and no endorsement of brand names or registered trademarks by the Clemson University Cooperative Extension Service is implied, nor is any discrimination intended by the exclusion of products or manufacturers not named. All recommendations are for South Carolina conditions and may not apply to other areas. Use pesticides only according to the directions on the label. All recommendations for pesticide use are for South Carolina only and were legal at the time of publication, but the status of registration and use patterns are subject to change by action of state and federal regulatory agencies. Follow all directions, precautions and restrictions that are listed.