How it works. Food held between 5°C and 60°C for less than 2 hours can be used, sold or put back in the refrigerator to use later. Food held between 5°C and 60°C for 2-4 hours can still be used or sold, but can't be put back in the fridge. Food held between 5°C and 60°C for 4 hours or more must be thrown away.