Calibration is the process of comparing the measurement values of an instrument or equipment with a known standard to determine its accuracy. The process can be done in-house using calibration equipment or by a third-party calibration service. The steps involved in the calibration process are selecting a standard, preparing the instrument, comparison, adjustment, and recording.
To illustrate how to perform a calibration, let’s consider an example of calibrating a digital thermometer used in a food manufacturing plant.
Selecting a standard. The first step is to select a reference thermometer with a known accuracy as the standard for comparison. The standard can be a reference instrument or equipment with known accuracy.
Preparing the instrument. Next, the thermometer must be prepared for calibration by cleaning and inspecting it to ensure it is functioning correctly.
Comparison. The next step is to take measurements with the thermometer and compare them to the reference thermometer to determine the accuracy of the instrument.
Adjustment. If the measurements are not within the acceptable range, adjustments can be made to bring them in line with the reference thermometer.
Recording. Finally, the calibration results are recorded in a calibration certificate, which includes information on the standard used, the calibration method, the date of calibration, and the accuracy of the thermometer.
