The U.S. Food and Drug Administration and the Centers for Disease Control and Prevention describe precautions for keeping food safe before, during, and after a power outage. Both agencies also describe how to handle food and water if flooding occurs. The Food and Drug Administration says the best strategy is to already have a plan in place, and notes that local officials will notify people of any evacuations or states of emergency.
Before a power emergency
The Food and Drug Administration advises keeping appliance thermometers in the refrigerator and freezer. It says the freezer should be at or below 0° F and the refrigerator at or below 40° F. Those thermometers show the temperatures during an outage and help determine whether food is safe, according to the agency.
The Centers for Disease Control and Prevention, in guidance dated Nov. 24, 2025, likewise says the refrigerator should be at 40°F or below and the freezer at 0°F or below. Both agencies describe freezing containers of water, and gel packs, to help keep food cold. The Food and Drug Administration says melting ice can also supply drinking water if the normal water supply is contaminated or unavailable.
The Food and Drug Administration advises freezing refrigerated items such as leftovers, milk, and fresh meat and poultry that may not be needed immediately. It says grouping food together in the freezer helps the food stay cold longer. Coolers should be on hand if the power will be out for more than four hours, the agency says, and ice cubes and gel packs can be frozen ahead of time for use in the refrigerator or in coolers.
The Food and Drug Administration says local sources should be checked to know where dry ice and block ice can be purchased. It says food should be placed on shelves where contaminated water would not reach it if flooding occurs. A supply of bottled water should be stored where it will be as safe as possible from flooding, the agency says, and bottled water with an odor should not be drunk or used.
If bottled water has an odor, the Food and Drug Administration says to dispose of it or, if applicable, call the bottled water provider to arrange a replacement. The agency also says that if food or beverage containers are used during an emergency to hold non-food substances such as gasoline, they should be disposed of after use and not recycled.
While the power is out
The Food and Drug Administration says refrigerator and freezer doors should be kept closed as much as possible to maintain the cold temperature. An unopened refrigerator will keep food cold for about four hours, the agency says. A full freezer will keep the temperature for approximately 48 hours, or 24 hours if it is half full, if the door remains closed.
The Centers for Disease Control and Prevention states the same limits if the doors stay closed: four hours in a refrigerator, 48 hours in a full freezer, and 24 hours in a half-full freezer. It says that if the power has been out for four hours and a cooler and ice are available, refrigerated perishable foods can be placed in the cooler. Ice, or a cold source such as frozen gel packs, can be added to keep them at 40°F or below, according to the agency.
The Food and Drug Administration says dry or block ice can be used to keep the refrigerator as cold as possible if the power will be out for a prolonged period. The agency says a fully stocked freezer of 18 cubic feet should stay cold for two days with 50 pounds of dry ice.
If refrigerated or frozen meat, poultry, fish, or eggs are eaten while they are still at safe temperatures, the Food and Drug Administration says each item should be thoroughly cooked to a safe minimum internal temperature. That step is meant to destroy any foodborne bacteria that may be present, the agency says. It says perishable food held at room temperature for two hours or more, or for one hour if outdoor temperatures are above 90º F, should be discarded.
After power returns
The Food and Drug Administration says that if an appliance thermometer was kept in the freezer, the temperature should be checked after electricity returns. A freezer thermometer reading of 40° F or lower means the food can go back into the freezer, according to the agency. If a thermometer was not kept in the freezer, each package should be checked, and the agency says appearance or odor cannot be relied on.
Food that still has ice crystals, or that measures 40° F or lower, can be cooked or returned to the freezer, the Food and Drug Administration says. The Centers for Disease Control and Prevention likewise says thawed frozen food that still contains ice crystals, or that is at 40°F or below, can be safely refrozen or cooked. The Centers for Disease Control and Prevention says food should never be tasted to decide whether it is safe, and states, “When in doubt, throw it out.”
The Food and Drug Administration says refrigerated food should still be usable after an outage of no more than four hours if the doors stayed shut. When power returns, the temperature in the refrigerator or of the food should be checked, the agency says. It says to throw out refrigerated items that spoil easily, including meat, poultry, seafood, milk, eggs, or leftovers, if they spent four hours or more above 40°F.
The Food and Drug Administration says perishable foods whose temperature, taken with a food thermometer, is no higher than 45°F can still be eaten, provided they are cooked and eaten without delay. The agency says meat, poultry, seafood, milk, and eggs can still make people sick if they are eaten after not being held cold enough in a refrigerator or freezer, and cooking them all the way through does not remove that risk. The Centers for Disease Control and Prevention says to throw out perishable refrigerator food, including meat, fish, cut fruits and vegetables, eggs, milk, and leftovers, after four hours without power or a cold source, and to throw out food that smells, looks, or feels unusual.
If flooding occurs
The Food and Drug Administration says only water from a safe source should be used for drinking and for washing or preparing food. Bottled water that has not been exposed to flood waters should be used if it is available, the agency says. If bottled water is not available, water should be boiled or disinfected.
If a well has been flooded, the Food and Drug Administration says the water should be tested and disinfected after flood waters recede. If contamination is suspected, the agency says a local or state health department or agricultural extension agent can be contacted for specific advice. Cloudy water should first be filtered through clean cloths, or allowed to settle so the clear water can be drawn off, before boiling or disinfecting, according to the agency.
Boiling water will kill most types of disease-causing organisms that may be present, the Food and Drug Administration says. The agency says the water should be boiled for one minute, then cooled and kept in covered clean containers. Household bleach does not eliminate every kind of disease-causing organism that the water may contain, the Food and Drug Administration says, though it does kill some of them. It describes adding one-eighth teaspoon, or eight drops, of unscented household liquid bleach at 5.25% concentration for each gallon of water, stirring well, and letting it stand for 30 minutes before use.
The Food and Drug Administration says not to eat any food that may have come into contact with flood water. Food and beverage that are not in a waterproof container should be discarded if there is any chance of contact with flood water, the agency says. It describes waterproof containers as undamaged, commercially prepared foods in all-metal cans and retort pouches, which it calls flexible, shelf-stable juice or seafood pouches.
The Food and Drug Administration counts screw-caps, snap lids, pull tops, and crimped caps among closures that do not keep water out. The agency says cardboard juice, milk, and baby formula boxes, and home-canned foods, should also be discarded if they contacted flood water, because they cannot be effectively cleaned and sanitized. Damaged cans should be discarded, including those with swelling, leakage, punctures, holes, fractures, extensive deep rusting, or crushing or denting severe enough to prevent normal stacking or opening with a manual, wheel-type can opener, the agency says.
The Centers for Disease Control and Prevention says to throw away food that smells, looks, or feels unusual, food whose packaging does not keep water out, and food that may have contacted floodwater or stormwater. Its list also covers cardboard containers and closures such as screw caps, snap lids, crimped caps, twist caps, flip tops, and snap tops, along with home-canned foods or cans that are bulging, open, or damaged. The agency states, “Unsafe food can make you sick even if it looks and smells normal.”
Saving packages and recognizing illness
Undamaged, commercially prepared foods in all-metal cans and retort pouches can be saved by a set procedure, the Food and Drug Administration says. Removable labels should be removed because they can harbor dirt and bacteria, and dirt or silt should be brushed or wiped away. The cans or pouches should be washed with soap and water, using hot water if available, then rinsed with water that is safe for drinking if available, because dirt or residual soap will reduce the effectiveness of chlorine sanitation, according to the agency.
The Food and Drug Administration describes two ways to sanitize those cans and pouches. One is to place them in water, bring the water to a boil, and continue boiling for two minutes. The other is to soak them for 15 minutes in a solution of one cup, or 8 oz/250 mL, of unscented household bleach at 5.25% concentration mixed with five gallons of water.
Cans or retort pouches should air dry for a minimum of one hour before opening or storing, the Food and Drug Administration says. If labels were removed, they should be replaced with a permanent marking pen, including the expiration date. Food in reconditioned cans or pouches should be used as soon as possible thereafter, the agency says. The Centers for Disease Control and Prevention describes a similar sequence for cans and plastic or metal pouches: remove labels if possible and note the expiration date, wipe away dirt, wash with hot soapy water, rinse with clean safe water, then sanitize by a 15-minute bleach soak or a two-minute boil, re-label, and use as soon as possible.
The Food and Drug Administration says metal pans, ceramic dishes, and utensils, including can openers, should be washed with soap and water, using hot water if available, then rinsed and sanitized. Sanitizing can be done by boiling them in clean water or immersing them for 15 minutes in one tablespoon of unscented household liquid bleach, at 5.25% concentration, per gallon of water, the agency says. Countertops should be washed, rinsed, and sanitized with that same bleach solution and allowed to air dry, according to the agency.
The Centers for Disease Control and Prevention describes a four-step process for dishes, utensils, and other surfaces that touch food, such as refrigerator drawers or kitchen countertops. The steps are washing with hot, soapy water, rinsing with clean, safe water, sanitizing, and air drying. Its sanitizing solution is one cup, or 8 oz/240 mL, of unscented household chlorine bleach in five gallons of clean water, with items soaked for one minute, or the solution applied with a cloth to surfaces that cannot be immersed.
The Centers for Disease Control and Prevention says wooden cutting boards, baby bottle nipples, and pacifiers should be thrown out if they have contacted floodwaters, because sanitizing methods are not effective for removing contaminants in floodwater from those items. For infants, the Food and Drug Administration says to try to use prepared, canned baby formula that requires no added water. Otherwise, concentrated baby formula in reconditioned all-metal containers should be diluted with clean drinking water, the agency says.
Consuming dangerous foodborne bacteria will usually cause illness within one to three days of eating the contaminated food, the Food and Drug Administration says. Sickness can also occur within 20 minutes or up to six weeks later, according to the agency. Symptoms can include vomiting, diarrhea, and abdominal pain, and flu-like symptoms such as fever, headache, and body ache. The agency says that if a person thinks that they or a family member has a foodborne illness, a healthcare provider should be contacted immediately.