The Danger Zone
The CDC's rule of thumb is that bacteria can multiply rapidly if food is left at room temperature or in the Danger Zone between 40°F and 140°F, which is 4°C to 60°C. Everything else follows from keeping food out of that band: the refrigerator sits below it, cooking takes food above it, and the time limits say how long food may pass through it.
| °F | °C | What it marks |
|---|---|---|
| 0 | -18 | Freezer. The FDA says food kept at 0°F stays safe indefinitely, though quality falls the longer it is frozen |
| 40 | 4 | Refrigerator, at or below. The top of the Danger Zone |
| 90 | 32 | Air temperature above which the 2-hour rule shrinks to 1 hour |
| 140 | 60 | Bottom of the Danger Zone; hot food held above it stays out of it |
| 145 | 63 | Whole cuts of meat and fish |
| 160 | 71 | Ground meat and egg dishes |
| 165 | 74 | Poultry, leftovers and casseroles |
The temperature converter handles any other value, and the oven temperature converter translates recipe settings, which are oven air temperatures and not the internal temperatures below.
The two-hour rule
The FDA's wording: refrigerate or freeze meat, poultry, eggs, seafood and other perishables within 2 hours of cooking or purchasing, and within 1 hour if the temperature outside is above 90°F. The CDC applies the same limit to any perishable food left out, and the FDA applies it to leftovers and takeout. The clock is cumulative: an hour on the buffet and an hour in a warm car is the whole allowance.
Safe minimum internal temperatures
Measured with a food thermometer in the thickest part, away from bone:
| Food | °F | °C | Note |
|---|---|---|---|
| Beef, pork, veal and lamb: steaks, chops, roasts; fresh ham | 145 | 63 | then rest 3 minutes before carving or eating |
| Fish with fins | 145 | 63 | or until the flesh is opaque and separates easily with a fork |
| Ground meats: beef, pork, veal, lamb | 160 | 71 | |
| Egg dishes | 160 | 71 | |
| All poultry, including ground chicken and turkey, parts, whole birds and stuffing | 165 | 74 | |
| Leftovers and casseroles | 165 | 74 | |
| Fully cooked ham, reheated | 140 | 60 |
The 3-minute rest for whole cuts is part of the rule: the temperature keeps rising and evening out after the meat leaves the heat. The meat cooking time calculator and the turkey cooking time calculator estimate how long a roast needs to get there, but time is only an estimate; the thermometer reading is the test. Dishes made with eggs need the 160°F figure; the egg timer covers boiled eggs by time.
Storing cold food
- Refrigerator at or below 40°F (4°C), freezer at 0°F (-18°C). The FDA gives both figures; an appliance thermometer confirms them.
- Freezing stops the clock but not the decline. The FDA says food will be safe indefinitely at 0°F, while quality decreases the longer it stays frozen. Date what goes in.
- Leftovers go in within 2 hours and are reheated to 165°F (74°C) throughout before serving, the same figure the table gives for leftovers and casseroles.
- Keep raw and ready-to-eat apart. The CDC's "separate" step: raw meat, poultry and seafood away from other food, in the cart, in the fridge and on the cutting board.
Thawing
The FDA lists three safe ways to defrost food: in the refrigerator, in cold water and in the microwave. The counter is not one of them, and the CDC spells out the reason: the outside of a frozen roast reaches room temperature, inside the Danger Zone, long before the centre thaws, so bacteria multiply in the outer layers while the inside is still frozen.
The short version
- Fridge at or below 40°F, freezer at 0°F.
- Perishables into the cold within 2 hours, 1 hour above 90°F.
- Whole cuts and fish to 145°F with a 3-minute rest, ground meat and egg dishes to 160°F, poultry and leftovers to 165°F.
- Thaw in the fridge, in cold water or in the microwave, never on the counter.
- Use a thermometer; colour and time are guesses.
Frequently asked questions
What is the Danger Zone in food safety?
The range between 40°F and 140°F (4°C to 60°C). The CDC says bacteria can multiply rapidly if food is left at room temperature or in that zone. Cold storage keeps food below it, cooking and hot holding keep food above it, and the time rules limit how long food may sit inside it.
How long can food sit out?
Two hours, and one hour when the air temperature is above 90°F. The FDA and the CDC state the rule the same way: refrigerate or freeze meat, poultry, eggs, seafood and other perishables within 2 hours of cooking or buying, within 1 hour above 90°F. The clock includes the time on the table and in the car.
What temperature should the fridge and freezer be?
The refrigerator at or below 40°F (4°C) and the freezer at 0°F (−18°C), per the FDA. A fridge thermometer is the only way to know; the dial numbers on most refrigerators are not temperatures.
Why is poultry 165°F but steak only 145°F?
The safe minimum temperatures come from what it takes to kill the bacteria typical of each food. Whole cuts of beef, pork, veal and lamb are safe at 145°F with a 3-minute rest, ground meat and egg dishes need 160°F, and poultry, leftovers and casseroles need 165°F. Grinding spreads surface bacteria through the meat, which is why ground beef needs more than a steak.
Can I thaw meat on the counter?
No. The FDA names three safe ways to defrost: in the refrigerator, in cold water or in the microwave. The CDC explains why the counter is out: the outer layers reach room temperature, inside the Danger Zone, long before the middle thaws.
Sources
- US Food and Drug Administration: Safe food handling (refrigerator at or below 40°F, freezer at 0°F; refrigerate within 2 hours, 1 hour above 90°F; the safe minimum internal temperature table; the three safe ways to thaw)
- US Food and Drug Administration: Are you storing food safely? (40°F and 0°F; the 2-hour and 1-hour rule for leftovers and takeout; food safe indefinitely at 0°F with declining quality)
- Centers for Disease Control and Prevention: Four steps to food safety (clean, separate, cook, chill; the Danger Zone between 40°F and 140°F; the safe temperatures; never thaw on the counter)