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Food Safety During a Power Outage

image of open refrigerator

When your refrigerator goes out, special food safety precautions must be taken to protect you and your household from foodborne illness during a power outage:

Milk, meat, and eggs should not be stored above 40F degrees for more than 2 hours. If a power outage is 2 hours or less there is no need for concern. 

Prepare before the power goes out:

  • Make sure you have appliance thermometers in your freezer.
  • Check to ensure the freezer is at or below 40F. 
  • Freeze containers of water to help keep food cold in the freezer, refrigerator, or cooler if the power goes out.
  • Freeze refrigerated items, such as leftovers, milk, and fresh meat that you may not need right away. This helps keep them at a safe temperature for longer.
  • Group food together (also helps keep food safe longer).
  • Keep coolers on hand to keep refrigerated food cold if the power will be out for more than 4 hours.
  • Purchase ice cubes in advance, and freeze gel packs ahead of time.
  • Store all of these in the freezer for future use in refrigerator or coolers.
  • Purchase dry or block ice to use when the power goes out.

When the power goes out:

Here are some basic tips for keeping food safe:

  • When it doubt, throw it out!
  • Keep the refrigerator and freezer door closed as much as possible to maintain the cold temperature.
  • The refrigerator will keep food cold for about 4 hours if unopened.
  • A full freezer will keep the temperature for about 48 hours if the door remains unopened (24 hours if 1/2 full).
  • Use dry or block ice to keep the refrigerator as cold as possible.
  • If you eat refrigerated or frozen poultry, fish, or eggs while still at safe temperatures, it is important that each item is thoroughly cooked to a safe internal temperature to ensure any foodborne illness bacteria is destroyed.

After power is restored:

  • Check the temperature using a device thermometer when the power is restored. If the thermometer reads 40F or below, the food is safe and may be refrozen.
  • If the thermometer has not been kept in the freezer, check each package to make sure it is 40F or below.
  • Refrigerated food should be safe as long as the power is out for no more than 4 hours, or the refrigerator was kept shut.
  • Discard any perishable food (meat, poultry, fish, eggs, and leftovers) that have been above 40F for 2 hours or more (or 1 hour if temperatures are above 90F).
  • Remember: Perishable food, such as meat, poultry, seafood, milk and eggs that are not kept refrigerated or frozen may cause foodborne illness, even when thoroughly cooked.

For more information, contact Environmental Health Services at (650) 372-6200, or read the Red Cross Food Safety Guide.