What does a change in value when a check standard is measured multiple times indicate?

A change in value when a check standard is measured multiple times primarily indicates drift. Drift refers to a gradual change in the measurement performance of an instrument over time, which can be caused by factors such as aging components, environmental conditions, or the wear and tear of the device. When measurements yield varying results over repeated checks, it suggests that the instrument’s performance is shifting and that it may require recalibration or adjustment to restore accuracy.

This is a crucial aspect of maintaining measurement reliability in calibration processes. Continuous monitoring with check standards helps identify drift, allowing technicians to take corrective actions. Recognizing drift is essential for ensuring measurement integrity in various applications, as it informs technicians when intervention is necessary to maintain the quality of measurements being taken.