What is the temperature danger zone, and how long can food safely remain in it?

• A. 50°F–140°F; up to 24 hours.
• B. 32°F–212°F (0°C–100°C); unlimited.
• C. 41°F–135°F (5°C–57°C); up to 2 hours (1 hour if ambient temp exceeds 90°F/32°C).
• D. 0°F–32°F (−18°C–0°C); up to 8 hours.

Answer: (C)

Bacteria grow most rapidly within a defined temperature band, so keeping food out of that zone minimizes the chance of harmful growth. The temperature danger zone is 41°F to 135°F (5°C to 57°C). In this range, bacteria can multiply quickly, so perishable foods should not stay there for long: at most two hours total, or one hour if the ambient temperature is above 90°F (32°C).

The other alternatives mix up the ranges or the timing. One option uses a not-standard TDZ and an impractically long time; another spans temps outside the zone and claims unlimited time; another is a freezing range, which doesn’t apply to TDZ rules. So the 41°F–135°F range with the two-hour (or one-hour in hot conditions) guideline is the accurate guidance.