A couple of years back, 600 million people in India were without power for two days. It was not only lights out – but lights out for half of the population. Can you imagine the chaos?
More recently, there have been significant power outages in North America. In late October 2012, Hurricane Sandy brought high winds and coastal flooding to a large portion of the eastern United States, leaving an estimated 8 million customers without power. Not quite as bad but serious none-the-less, the ice storms of December 2013 cumulatively left over 1 million people without power.
When the power goes out (commonly called “grid down”), so do transportation systems, manufacturing systems, communications systems and of course, household systems. And what about those household systems? The first thing that comes to mind is heating and cooling when the temperate drops to below freezing or the heat swelters to 90 degrees Fahrenheit with 80% humidity.
Personal comfort aside, there is a big issue with our dependence on refrigeration in keeping food safe. In recent weeks, I have been asked about food safety when the grid is down. One of the more specific questions has been “what is safe to eat after thawing and being re-frozen following a power outage?”.
I can not say that I am an expert on the subject but I can share some guidelines to follow when the power grid goes down for more than a few hours.
Keeping Food Safe When the Power Goes Out
1. Place appliance thermometers in both the refrigerator and the freezer. After a power outage, check the temperature to determine whether your food is still safe to consume. Safe temperatures are 40°F or lower in the refrigerator, 0°F or lower in the freezer.
2. Keep your freezer as full as possible. Fill empty juice or milk jugs with water and keep them in the freezer (unless you need the space for food, of course). If the power grid goes down, you can use these frozen blocks of ice to maintain the cold temperature in your refrigerator and/or to keep the temperature in your freezer colder for a longer period. A full freezer will hold its temperature for about 48 hours but only 24 hours if half-full.
3. Place ice cubes in zipper type bags and place them in the freezer. Later, if the power goes out, keep the freezer door closed. When the power is restored, leave the freezer door closed long enough for it to go back to its normal, freezing temperature. If the ice cubes have melted into a bag of solid ice, you will know that everything in the freezer thawed and is likely unsafe.
4. Have a minimum of a week’s supply of ready-to-eat food that does not require cooking or refrigeration after being opened.
5. Do not open the refrigerator and freezer doors unnecessarily. Take out what you need quickly then close the doors and keep them closed. A refrigerator will keep food cold for four to six hours if the door is kept closed.
6. Have coolers on hand that can be used to store the refrigerated foods that you think you will need for the short term. Use the frozen jugs of ice from your freezer to keep the food in your cooler cold. This will mitigate having to open and close the refrigerator door unnecessarily.