By Meron Tesfai

Safe food handling is important in every day life, however in an emergency like a power outage, it is especially important.

Generally, refrigerated foods are safe as long as the power is out for no more than four hours if the door is not opened. Always keep meat, chicken, fish and eggs refrigerated at or below 40 °F and frozen food at or below 0 °F.  When power is restored, check all food accordingly.

Steps to take:

  • Never taste food to determine its safety.
  • Obtain a dry or block of ice to keep your refrigerator and freezer as cold as possible if the power outage will be ongoing.
  • Fifty pounds of dry ice should hold an 18-cubic-foot full freezer for 48 hours.
  • If a thermometer has not been kept in the fridge then check the temperature of each food item, if it is at 40 °F or below, the food is safe.
  • After 4 hours without power, throw out perishable foods like meat, chicken, fish, soft cheeses, milk, eggs, deli items, and leftovers.

Frozen Foods:

A full freezer will keep food frozen for about 48 hours. A freezer that is half full will keep food frozen for about 24 hours.  The kind of food in the freezer makes a difference; meats and vegetables will stay frozen longer than bread. To preserve food in your freezer, keep the door closed as much as possible.


If flooding has occurred:

  • Use bottled water to drink, boil or disinfect tap water for cooking, cleaning and bathing.
  • Wash all dishes that come in contact with floodwater with hot soapy water.
  • Sanitize the dishes by boiling them in clean water or putting them in one teaspoon of chlorine bleach per gallon of clean water for 15 minutes.
  • Food may safely be refrozen if the food still contains ice crystals or is at 40 °F or below.

Throw Out:

If floodwater comes in contact with these items, throw them out.

  • Spices, seasonings, sugar, grain, coffee, flour.
  • Canned foods including those bought in stores or home caned, unopened jars with cardboard seals like salad dressings.
  • Meat, chicken, eggs or fish or any of other foods that have come in contact with raw meat juices.
  • Foods stored in cardboard boxes, cloth, paper, foil or cellophane.
  • Plastic dishes, wooden cutting boards, baby bottles and pacifiers.

What to Keep:

  • Dishes that have been sanitized by boiling in clean water and placed for 15 minutes in a solution of one teaspoon of chlorine bleach per gallon of clean water.
  • Canned foods that did not come into contact with floodwaters.

Be sure to carefully inspect all food items and do not eat any food you think may not be safe. Spoiled food may not look contaminated. Remember, when in doubt, throw it out.

Preventing Illness:

If floodwater is present, it is important to avoid the water as much as possible in order to protect yourself from disease that can be carried by germs in the water.

  • Avoid skin contact with sewer water, especially cuts and sores. Keep them clean and covered.
  • Do not allow children to play in areas contaminated by sewage backup.
  • Do not eat or drink anything exposed to sewer water.
  • Keep contaminated objects, water and hands away from your mouth, eyes and nose.
  • Wash hands frequently, especially after bathroom use, before eating and immediately following contact with sewer water or contaminated objects.


The need for tetanus vaccination after exposure to flood water depends on a few factors.  Exposure alone does not increase the risk for tetanus, the presence of a cut or wound, the condition of the wound and the likelihood that he person is at risk of getting sick from tetanus are all factors to consider.  Talk to your health care provider about the need for a tetanus vaccine if you are at risk. Don’t have a health care provider? Call the Mayor’s Health Line at (617) 534-5050.

For more information about food safety and preventing injury and illness in an emergency, please click here and here.

Meron is a project manager in the Education & Outreach Office of our Infectious Disease Bureau.