The 2-Hour / 4-Hour Rule: How Long Food Can Be Out of the Fridge
The 2-hour/4-hour rule for food in the danger zone: when to use, refrigerate or discard potentially hazardous food, and how the cumulative time is counted.
The 2-hour/4-hour rule is a guide for how long ready-to-eat, potentially hazardous food can safely be in the temperature danger zone (5°C–60°C). Under 2 hours total, it can be used or refrigerated; between 2 and 4 hours it should be used immediately; beyond 4 hours it should be thrown out. The time is cumulative across the food's whole life. Key takeaways: Under 2 hours in the danger zone: use it or put it back in the fridge.. 2 to 4 hours: use it now — don't refrigerate it again.. Over 4 hours: throw it out.. The clock is cumulative across the food's entire life, not reset each time.. The 2-hour / 4-hour thresholds: Total time in the danger zone (5–60°C), What to do. Under 2 hours — Use it, or put it back in the fridge. 2 to 4 hours — Use it now — don't refrigerate it again. Over 4 hours — Throw it out. What the rule actually says The rule applies to ready-to-eat potentially hazardous food that has been in the 5°C–60°C range. It counts the total time the food has spent in that zone across receiving, prep, display and service — not just the current sitting. Once you know the total, you know whether to use, refrigerate or discard it. Why time is cumulative Bacteria don't reset when food goes back in the fridge. If a tray of chicken spent 1 hour out during prep and later another 1.5 hours on display, that's 2.5 hours total — so it should be used immediately, not chilled again. Tracking cumulative time is the part most businesses get wrong. Making it workable on a busy floor Label prepared food with the time it came out of temperature control, or track it on a display sheet. Prepare and display in smaller batches so food isn't sitting in the zone longer than needed, and top up rather than leaving a full tray out for hours. Worked examples: Adding up a tray of chicken's time: A tray of cooked chicken spent 1 hour out of temperature control during prep, then later another 1.5 hours on display. That is 2.5 hours total in the danger zone, so under the rule it should be used immediately, not chilled again. The clock is cumulative across the food's whole life, so the earlier hour still counts. Checklist: Prepared foods labelled with the time they left temperature control. Cumulative danger-zone time tracked, not per-sitting. Food over 4 hours discarded. Food between 2–4 hours used, not re-chilled. Common mistakes: Resetting the clock each time food goes back in the fridge. Refrigerating food that has already been out for 3 hours. Guessing the time instead of labelling when food came out. Leaving a large batch on display for the whole service.
How to apply the 2-hour/4-hour rule
Record the time cold food leaves the fridge or hot food drops below 60°C.
Include every period the food has been between 5°C and 60°C across its life.
Under 2h: use or refrigerate. 2–4h: use immediately. Over 4h: discard.
Logging the decision shows an inspector you're managing time actively.
Frequently asked questions
Does the 2-hour/4-hour rule apply to all food?
It applies to ready-to-eat potentially hazardous food. Foods that aren't temperature-sensitive (like most dry, canned or high-acid foods) don't need the rule, and raw food destined for thorough cooking is managed differently.
If food has been out for 3 hours, can I refrigerate it?
No. Between 2 and 4 hours the food should be used immediately, not put back in the fridge. Only food that has been out for less than 2 hours total can safely be refrigerated for later use.
Is the rule a law?
It is a widely used guideline based on FSANZ guidance for keeping food safe when it can't be kept under strict temperature control. Your food safety program or regulator may reference it; it's a practical way to meet the underlying requirement to keep food safe.
Does the clock reset when I put the food back in the fridge?
No. Bacteria don't reset when food goes back in the fridge, so the time is cumulative across the food's entire life, not reset each time. Add up every period the food has been between 5°C and 60°C across receiving, prep, display and service. Tracking cumulative time is the part most businesses get wrong.
How can I keep track of danger-zone time during a busy service?
Label prepared food with the time it came out of temperature control, or track it on a display sheet, so the total is easy to add up. Prepare and display in smaller batches so food isn't sitting in the zone longer than needed, and top up rather than leaving a full tray out for hours. Recording your decision also shows an inspector you're managing time actively.