Calibration Fundamentals

Calibration determines the accuracy of measuring instruments by comparing its value to a higher-level measurement standard, usually a working standard gage block. Measurement standards follow a hierarchy consisting of primary, secondary, and working standards. Traceability links these standards together. Measurement uncertainty estimates the accuracy of a measurement. It is the range in which the true value of a measurement is expected to lie. High-accuracy parts require tight tolerances. Tighter tolerances require higher-accuracy measuring instruments. While uncertainty and error exists in every measurement, careful calibration can help to minimize inaccuracy when inspecting parts with measuring instruments. After taking this class, users should be able to explain how calibration and traceability impact the use and care of inspection devices.