Food safety when the refrigerator is out of power

According to USDA - US Department of Agriculture and CDC - US Centers for Disease Control, refrigerated and frozen foods may no longer be safe after a power outage. They also provide some recommended steps with the foods in your fridge:
1.1. With a refrigerator Keep a thermometer in your refrigerator and freezer (if possible). The refrigerator should be at 5°C or below, the freezer should be at -18°C or below. Avoid opening the refrigerator or freezer door unnecessarily. If covered, food will stay cold longer - a closed refrigerator will keep food cold for about four hours. A full freezer will keep the temperature for about 48 hours (24 hours if half full). Set meat and poultry aside on the freezer tray: this prevents contamination from cross-contaminating the vegetables or fruits. Use dry ice or block ice in the refrigerator to keep it as cool as possible. About 22.7kg of ice can keep a 5.4m high freezer cold for 2 days.

1.2. Store food in the refrigerator during a power outage Check the foods inside the freezer and refrigerator: discard any perishable foods such as meat, fish, eggs, leftovers if they are already at room temperature. above 5°C for two hours or more. Do not use any foods that have an unusual smell, color, texture, or feel warm to the touch. Check frozen foods for ice crystals. Food in your freezer that has been partially or completely thawed can be safely refrozen if it still contains ice crystals or the temperature is 4.5°C or below. Never taste foods to see if they are still usable.

References: foodsafety.gov, today.com