WASHINGTON, Aug. 28 (UPI) -- Should the power go out due to Hurricane Isaac or any other storm, U.S. officials advise residents to keep refrigerator and freezer doors closed.
The U.S. Department of Agriculture's Food Safety and Inspection Service said a refrigerator will keep food cold for about 4 hours if the door is kept closed, a full freezer will keep its temperature for about 48 hours -- 24 hours if half-full.
"If the power is out for an extended period of time, buy dry or block ice to keep the refrigerator as cold as possible," FSIS officials said in a statement. "Fifty pounds of dry ice should keep a fully-stocked 18-cubic-feet freezer cold for two days."
The FSIS also advises to:
-- Check refrigerator thermometer, it should be 40 degrees F or below to keep food safe.
-- Freezers should be at 0 degrees or lower, but if a freezer has no thermometer, check each package of food. If food still contains ice crystals or is at 40 degrees F or below when checked with a food thermometer, it may be safely refrozen.
-- Discard any perishable food -- meat, poultry, fish, soft cheeses, milk, eggs, leftovers and deli items -- kept in a refrigerator or freezer above 40 degrees F for 2 hours or more.