在通过ISO 17025认证的实验室进行校准

Calibration is defined as "an activity which, under specified conditions, establishes a relationship between the quantity values provided by standards with their measurement uncertainties and the corresponding indications with their associated measurement uncertainties and, in a second step, a relationship by means of which a measurement result is obtained from an indication" (International Dictionary of Metrology). Only calibration by an accredited laboratory can provide and verify this required metrological proof with international acceptance.