USDA-based · How this page was made · Last reviewed August 31, 2026 · Sources ↓
The picnic and buffet clock: 2 hours, or 1 hour above 90°F
Hot food stays safe only if it stays at 140°F or warmer. Cold perishable food stays safe only if it stays at 40°F or below. Once it leaves that hold, the clock is 2 hours at room temperature, or 1 hour if the air is above 90°F — a summer picnic, a hot car. Discard anything that misses the clock. At a buffet, keep hot food in chafing dishes, slow cookers, or warming trays; nest cold dishes in ice; use small trays and replace them often.
The two-hour rule is not a suggestion to reheat later. Miss the clock and discard it.
Hold temperatures first
FSIS: hot food should be held at 140°F or warmer; cold food at 40°F or colder. Use a food thermometer to check holding temperatures. While food stays in those ranges, the picnic clock is not running the same way it does on the counter.
The clock once food leaves the hold
Perishable food must not sit at room temperature more than 2 hours — 1 hour when the temperature is above 90°F (outdoor picnic, hot car). Discard anything that misses that clock. Do not “just reheat” after a missed clock; some toxins survive cooking. See the danger zone guide for why — this page does not rewrite it.
Buffet setup
Keep hot food in chafing dishes, slow cookers, or warming trays. Keep cold food cold by nesting dishes in bowls of ice, or use small serving trays and replace them often (FSIS leftovers + steps-keep-food-safe).
After the meal
Leftovers that were held safely and refrigerated on time still need the 165°F reheat rule.
Sources
- USDA FSIS: Leftovers and Food Safety — USDA FSIS, 2026
- USDA FSIS: Keep Food Safe! Food Safety Basics — USDA FSIS, 2024