FRIDGE
UP TO 4 HOURS
The FSA says a fridge should stay cold for up to four hours with the door kept closed as much as possible.
FULL FREEZER
UP TO 48 HOURS
A full freezer can keep food frozen for up to 48 hours. A half-full freezer is estimated at up to 24 hours.
If the cut lasts longer
Keep doors closed. If you have a fridge thermometer, the FSA says food can remain stored in a fridge below 8°C during a power cut. If the fridge reaches 8°C or above, prioritise eating food that normally requires refrigeration within four hours.
These are estimates; appliance design, room temperature and how often doors are opened all affect the result. Follow current FSA advice for the specific food in question.