Calibration of Thermometers

Policy:

Thermometers will be calibrated routinely to ensure accuracy of temperatures taken and that food is served to customers at safe temperatures.

Procedure:

A designated employee will calibrate thermometers on a weekly basis using the following steps:

Calibrating Thermometers –Ice-Point Method

Note: The ice-point method of calibrating thermometers should be used, unless a thermometer cannot read 32°F; the boiling-point method is sometimes less reliable due to variations in altitude and atmospheric pressure.

1. Fill a large glass (at least 6” in diameter) with crushed ice. Add cold, clean tap water until the glass is full. Stir the mixture well so that it will be at 32°F.
2. Put the end of the clean thermometer or probe stem into the ice water so that the sensing area is completely submerged, but the stem does not touch the bottom or sides of the glass. Wait 30 seconds. The thermometer stem or probe stem must remain in the ice water.
3. Hold the adjusting nut on a dial thermometer, located under the indicator head of the thermometer, secure with a small wrench or pliers, and rotate the head of the thermometer until it reads 32°F.
4. Press the reset button on a digital thermometer to adjust the readout.
5. Record in Calibration Record for Thermometers that calibration was completed, including date and initials of person verifying.

Calibrating Thermometers –Boiling-Point Method

1. Bring clean tap water to a boil in a deep pan (it will be at 212°F).
2. Put the stem of a clean thermometer or probe into the boiling water so that the sensing area is completely submerged but does not touch the bottom or sides of the pan. The thermometer or probe stem must remain in the boiling water for 30 seconds. Use a hot pad to hold the thermometer in the boiling water.
3. Hold the adjusting nut on a dial thermometer, located under the indicator head of the thermometer, securely with a small wrench or pliers, and rotate the head of the thermometer until it reads 212°F.
4. Press the reset button on a digital thermometer to adjust the readout.
5. Record in Calibration Record for Thermometers that calibration was completed, including date and initials of person verifying.

The restaurant manager will:

1. Review the Calibration Record for Thermometers weekly to ensure that thermometers were calibrated.
2. Follow-up as necessary.
3. File logs with HACCP records.