Resilience & food safety
Two timers start the moment supply drops: four hours on the fridges, forty-eight on a full freezer. Here is the sequence that keeps the stock, the record and the restart safe.
When the lights go
The moment supply drops, every fridge, freezer, hot-hold and extract fan in the building stops doing its job - and two timers start running. One is the roughly four hours a closed fridge holds temperature. The other is the 48 hours a full, unopened freezer stays frozen.
Kitchens that come through outages cheaply are not lucky; they have a plan the whole brigade knows before it happens. The sequence below is written to be printed, laminated and stuck inside the dry store door. It follows the Food Standards Agency's power cut guidance and the temperature rules your food safety management system already uses.
The sequence
Before it ever happens
Everything above works better with an hour of preparation done in daylight. Fit a battery or dial thermometer in every unit so you are not blind when the digital displays die with the power. Keep a stock of insulated boxes and frozen gel packs. Know your electricity network operator's fault line (105 from any phone in Great Britain) and your account reference. And decide in advance who owns the log, because the paperwork is the part that gets forgotten at 7pm on a Friday - the same discipline covered in our piece on the paper trail inspectors expect.
It is also worth deciding your stock strategy calmly. Kitchens running cook-chill systems hold days of production in the chill chain, which concentrates the risk of a long outage into one place; the trade-offs are covered in our comparison of cook-chill and cook-freeze operations. Whatever the model, the rule is the same: the food's history decides its fate, and you can only prove that history if you wrote it down.
The numbers that decide it
These are planning lines, not guarantees - cabinet age, ambient heat and door discipline all move them. When any food's temperature history is unknown, the old rule stands: if in doubt, throw it out.
Questions
Yes, if it never really thawed. Food that still contains ice crystals, or has stayed at fridge temperature or below, can be safely refrozen or cooked, though quality may suffer. Anything fully thawed and warm goes in the bin - never judge safety by look or smell, because the bacteria that cause food poisoning change neither.
Almost never. If your cookline sits under an extraction canopy with a gas interlock - required on installations since 2001 under BS 6173 - loss of the extract fan means ventilation cannot be proven and gas is cut or must not be used. Cooking under a dead canopy fills the kitchen with combustion products and grease-laden vapour, so plan for a cold menu instead.
There is no automatic duty to report a power cut itself, but your food safety management system must show how you handled it: timings, temperatures, what was discarded and why. If you served food during or after the outage and its safety is later questioned, that written record is your defence. When in doubt about a specific situation, your local authority food team will advise.
Phoenix Duct Clean · by the numbers
Cold rooms, drains and wash-up areas deep cleaned before you restock - with the certificate for your file.