Power outages can threaten food safety and cause food loss for operations like cafeterias, food pantries, hospitals, restaurants, and grocery stores. The United States Department of Agriculture's (USDA) Food Safety and Inspection Service (FSIS) provides the following information to help reduce food loss and minimize the risk of foodborne illness.

To prepare for emergencies, keep thermometers in refrigerators and freezers to help evaluate food safety during power outages. The temperature should never rise above 40° F in the refrigerator and 0° F in the freezer. In both the refrigerator and freezer, group foods together—this will help them stay cold longer if the power goes out. Freeze foods like milk, meat, and poultry to allow them to stay at a safe temperature longer. Keep portable coolers handy to store refrigerated food when the power will be out for more than four hours. Store ice and gel packs in the freezer for use in refrigerators and coolers.

If a power outage occurs, make sure freezer and refrigerator doors stay closed as much as possible. A freezer will keep its temperature for two days when full and one day when half-full, and a closed refrigerator will keep food cold for about four hours. If possible, have generators ready to power them during power outages. Make sure to plan ahead and know where to purchase block ice to keep refrigerators cold if a generator is not available and the power is out for more than four hours. If you have to handle block ice, protect yourself by wearing proper safety glasses, gloves, and footwear.