Meaning of calibration

The activity of determining that the indication error of measuring instruments meets the prescribed requirements through experiments and proof provided by the legal metrology department or legally authorized organization in accordance with the verification regulations.

Meaning of calibration

Under specified conditions, in order to determine the indication value of measuring instruments or measurement systems, or the indication value represented by physical measuring tools or standard materials, high precision calibrated qualified standard equipment and the measured equipment are used to test the same measured object, and a set of operations are performed to obtain the relative error of the measured equipment compared to the standard equipment, thereby obtaining the corrected value of the measured equipment's indication data.

The main difference between verification and calibration

Different purposes

The purpose of calibration is to compare the measurement standards, evaluate the indication error of the measuring device, ensure the accuracy of the measurement value, and belong to a set of bottom-up measurement value traceability operations.

The evaluation of this indication error should be made according to the organization's calibration procedures, according to the calibration cycle, and calibration records and labels should be kept. In addition to evaluating the indication error of the measuring device and determining the relevant metrological characteristics, calibration results can also be expressed as correction values or calibration factors, which guide the operation of the measurement process.

The purpose of calibration is to conduct a mandatory comprehensive evaluation of the measuring device. This comprehensive evaluation belongs to the category of unified values and is a top-down process of value transmission. Verification should evaluate whether the measuring instruments meet the specified requirements. This regulation requires the error range specified in the calibration regulations for measuring devices. Evaluate whether the error range of the measuring device is within the specified error range through calibration.

Different objects

The object of calibration is a measuring device that falls outside of mandatory verification. The non mandatory calibration of measuring devices in our country mainly refers to the measuring instruments widely used in the production and service provision process, including the measuring instruments used in incoming inspection, process inspection, and final product inspection.

The object of verification is the measurement device that is clearly defined as mandatory verification by China's Metrology Law. Article 9 of the Metrology Law of the People's Republic of China clearly stipulates that the metrological administrative departments of the people's governments at or above the county level shall carry out compulsory verification on the social public metrological standard instruments, the highest metrological standard instruments used by departments, enterprises, and institutions, as well as the working metrological instruments listed in the mandatory inspection catalog for trade settlement, safety protection, medical and health, and environmental monitoring. Those who fail to apply for verification according to regulations or fail verification shall not be used.

Therefore, the main objects of verification are three categories of measuring instruments. This is:

1. Measurement standards (including international and national standards) are defined in ISO 10012-1 "Quality Assurance Requirements for Measurement and Testing Equipment".

The ISO 10012-1 standard defines "metrology" as a physical measuring instrument, measuring instrument, standard substance or system used to define, implement, maintain, or reproduce units or one or more known quantity values, and transmit them to other measuring instruments through comparison.

3. According to the detailed regulations of China's Metrology Law and the People's Republic of China's mandatory calibration of work measuring instruments, all instruments used for trade settlement, safety protection, medical and health, and environmental monitoring shall be subject to mandatory calibration. In this detailed catalog, it is clearly stated that