How to protect food during a power cut

What official guidance says

The Food Standards Agency guidance for England, Northern Ireland and Wales says that an outage shorter than four hours is unlikely to affect food in chilled or frozen storage. It advises keeping the doors closed, using a fridge thermometer where possible and treating the four-hour fridge, 48-hour full-freezer and 24-hour half-full-freezer figures as estimates.^[1]

Food Standards Scotland gives the same broad household advice for Scotland. It notes that appliance type and room temperature affect how long food remains cold.^[2]

Prepare your fridge and freezer before a power cut

There is no need to turn routine food shopping into emergency stockpiling. A thermometer, a small amount of non-perishable food and a simple note of what is in the freezer can make a later decision calmer and clearer.

The UK Government recommends non-perishable food that does not need cooking, bottled water and a tin opener. It also advises keeping doors closed during an interruption. A freezer inventory is a practical household choice, not an official requirement.^[3]

What to do when the power goes off

Preserve the cold air already in the appliances. Avoid opening the fridge or freezer to inspect individual items. Record when the outage began. If the fridge stays below 8°C, food can remain there during the outage. If it reaches 8°C or above, eat food that normally needs refrigeration within four hours. If power is not restored within that time, discard it.^[1]

If the outdoor temperature is below 8°C, the FSA says suitable food can be stored outside in clean, dry conditions, out of direct sunlight and protected from animals in a sealed container. This is an official option for suitable conditions, not a reason to leave food exposed outdoors.^[1]

How long will a freezer stay cold?

A full freezer may stay frozen for up to 48 hours and a half-full freezer for around 24 hours if it remains closed. The appliance, room temperature and door opening all affect the result. Keep the door closed, record the time and use official guidance if food starts to thaw.^{[1] [2]}

Who should be especially cautious?

The FSA identifies young children, pregnant women, older people and people with underlying health conditions as groups who may be at greater risk from food poisoning. Take extra care with ready-to-eat chilled food, deli meats and smoked fish.^[1]

If you are preparing infant formula during a power cut, follow the NHS guidance. Powdered formula requires freshly boiled water that has cooled for no more than 30 minutes so it remains at least 70°C. If boiling water is not available, ready-to-use formula may be an option.^[4]

Practical conclusion

Most household power cuts are short. Keep the doors closed, use a thermometer if available and note the time. For a longer interruption, use the official guidance to prioritise chilled food and make cautious decisions. If you are checking a packaged food item for a current safety alert, search RecallBite’s live recalls by product name, brand, lot code, batch code or available barcode.