"Calibration" is the act of comparing a measurement device against a known and traceable standard.
Set of operations that establish, under specified conditions, the relationship between values of quantities indicated by a measuring instrument or measuring system, or values represented by a material measure or a reference material, and the corresponding values realized by standards.
NOTE 1. The result of a calibration permits either the assignment of values of measurands to the indications or the determination of corrections with respect to indications.
NOTE 2. A calibration may also determine other metrological properties such as the effect of influence quantities.
NOTE 3. The result of a calibration may be recorded in a document, sometimes called a calibration certificate or a calibration report.
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