Difference one, different management bodies
Mandatory calibration by the government measurement of the administrative department of the statutory metrological certification bodies or authorized measurement and certification bodies to carry out supervision and management;
Non-compulsory calibration of measuring instruments by the use of their own units or entrusted to have a public standard of measurement or authorized by the metrological calibration body of their own legal management.
Difference between two, different calibration cycle
The mandatory calibration of the calibration cycle is mandatory, the calibration relationship is fixed, the fixed point of regular inspection;
Non-compulsory calibration of the calibration cycle, according to the actual use of measuring instruments by the enterprise in accordance with the principles of science, economy and the accuracy of the value of the self-service determination.
Mandatory verification is the public standard of measurement of society, departments and enterprises and institutions using the highest standard of measurement for trade settlement, safety and security, medical and health care and environmental monitoring in four areas included in the national mandatory inspection of the catalog of work measuring instruments.
Expanded Information:
p>Can be divided into the following five categories:
1, according to the level of accuracy can be divided into in a particular field with the highest metrological characteristics of the benchmark and the benchmark to determine the value of the sub-benchmark by comparing with the benchmark, or with a different accuracy of the various levels of standards;
2, according to the composition of the structure can be divided into a single standard, or by a group of the same standard composed of a group of standards through the use of the joint role of standardizer Standards, or a group of standards with different specific values of a group of standards, individually or in combination to provide a given range of values of a series of standards;
3, according to the scope of application can be divided into the international agreement recognized by the international standard, used in the international determination of the amount of other standards, or by the official decision of the State, recognized in the country for the determination of the amount of other standards of standards National standard, or reference standards with the highest metrological characteristics available at a given location;
4, according to the nature of the work can be divided into daily used to calibrate or test measuring instruments working standard, or used as an intermediary to compare the measurement standards or measuring instruments transfer standard, or sometimes have a special structure, transportable standard;
5, according to the work of the Principle can be divided into by the material composition, size, etc. to determine the value of the physical standard or by physical laws to determine the value of the natural standard.
Baidu Encyclopedia - Compulsory Certification
Baidu Encyclopedia - Non-compulsory Certification