A power outage can occur due to severe weather or natural disasters, vehicle accidents near power lines, and high energy demands, among other reasons.
Utility workers can usually fix a minor accident — such as a downed power line — in a few hours, but when the cause is related to severe weather or a natural disaster, it may take days or even weeks to restore power.
In either case, it’s important to know how to keep food safe during a power outage, especially if you work in a nursing home or other healthcare facility where residents or patients depend on you for meals.
This article explains how to keep food safe during a power outage and how long you can safely keep refrigerated and frozen foods.
Before a power outage
You should always be prepared for a power outage, especially if you live in an area where high winds from hurricanes, tropical storms, or tornadoes are common.
Make sure fridges maintain a maximum temperature of 41ºF (5ºC) and freezers a temperature cold enough to keep food frozen, usually around 0ºF (-18ºC) (1).
In preparation for a storm, you can purchase dry ice or block ice to keep your food colder for longer in the fridge.
Reducing the freezer temperature and moving foods that you don’t need immediately from the fridge to the freezer can keep them cold for longer.
You can also stack or bring cold food close together — while still being careful to avoid cross-contamination — to keep them cold.
If you’re a nursing home or healthcare facility, review your disaster menu and make sure you have several days’ worth of nonperishable food — including gallons of water — to use the menu.
Even if you don’t use chafing dishes, keeping one on hand with fuel is a good strategy to keep hot-held food warm once a power outage occurs.
Keep flashlights with fresh batteries and lighters on hand.
Prepare for a power outage by maintaining your fridge and freezer at the proper temperature and purchasing dry or block ice. If you’re a nursing home or other healthcare facility, make sure you have enough food and water on hand to use your disaster menu.
During a power outage
The first thing to do when a power outage occurs is to write down the time so you can track how long you were without power.
Unlike food in dry storage, food in fridges and freezers is vulnerable to spoilage and bacterial growth.
This is because they are time-temperature controlled for safety (TCS).
Keep the fridge and freezer doors closed as much as possible to prevent cold air from escaping.
You can safely keep food in the fridge for up to six hours without power as long as the temperature doesn’t exceed 70ºF (21ºC).
Food can stay safe for up to 48 hours in a full freezer and for 24 hours in a half-full freezer.
Discontinue all cooking operations and, if you’re a healthcare facility, turn to your disaster menu.
Toss any food that is being cooked at the time of a power outage but has not reached a safe internal cooking temperature.
Food that has reached a safe internal cooking temperature can be cooled using the two-stage method and then stored in the fridge or freezer.
Food that was being hot-held at 135ºF (57ºC) can be kept warm using chafing dishes or tossed after four hours without temperature controls.
Write down the time of the power outage. Discontinue all cooking operations and focus your attention on keeping the TCS foods inside the fridge and freezer cold for as long as possible.
After a power outage
Once the power is restored, write down the time, and determine the time you were without power.
Refrigerated food may be safe to keep if you were without power for six hours or less.
However, you still need to check the temperature of each food using a calibrated thermometer and toss any food above 70ºF (21ºC).
You don’t need to toss non-TCS foods that you may normally keep in the fridge like ketchup, mustard, olives, jelly, vinegar-based dressings, butter and margarine, most baked goods, and whole fruits and vegetables.
You can refreeze previously frozen food as long as its temperature didn’t exceed 41ºF (5ºC), otherwise, check it for signs of spoilage and keep it in the fridge.
But keep in mind that fridges and freezers take several hours to reach the proper temperature so you must continuously temp the food to make sure it doesn’t exceed 70ºF (21ºC) during this process.
Depending on how long you were without power, you may need to wipe up water from frost and ice that melted and then wash all interior surfaces of the fridge and freezer.
Just make sure to remove the food first.
If your freezer doesn’t have a self-defrost feature, now may also be a good time to defrost it — if it isn’t already.
After power is restored, toss any refrigerated food that exceeded 70ºF (21ºC). Frozen food below 41ºF (5ºC) can be refrozen. Clean up any spills and wash the fridge and freezer floors and walls.
The bottom line
You should always be prepared for a power outage, especially if you live in an area with frequent severe weather.
Refrigerated foods kept at 41ºF (5ºC) or below can last up to six hours without power as long as it doesn’t exceed 70ºF (21ºC).
Frozen food can last up to 48 hours in a full freezer or 24 hours in a half-full freezer.
Once power is restored, clean up any spills and wash the inside of the fridge and freezer after removing the food.
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