Food in a refrigerator is generally safe for about 4 hours without power if the door remains closed. For freezers, a full freezer will keep food frozen for about 48 hours (24 hours if half full) if unopened. Opening the doors frequently accelerates warming and decreases the safety time. Perishable items like meat, poultry, fish, dairy, and leftovers should be discarded if kept above 40°F (4°C) for more than 2 hours after power is lost. Use dry or block ice to extend safe storage time during prolonged outages. When in doubt, throw food out to avoid foodborne illness risks. This guidance is based on recommendations from food safety authorities like the FDA and CDC.