Tool
Thermometer check
Food thermometers scaled only in Fahrenheit are accurate to ±2°F (4-203.11(B)) and are calibrated as the manufacturer specifies (4-502.11(B)).
Check a thermometer
✓Reads 33°F in ice water: within ±2°F of 32°F.
Worked example. With JavaScript on, the result follows what you type.
±2°F
The accuracy of a Fahrenheit food thermometer (4-203.11(B)).
32°F
What ice water reads. A probe further off than 2°F is recalibrated or replaced.
Calibration
As the maker of the thermometer specifies (4-502.11(B)). Batch Log keeps each check with the date and the name of the probe.