Difference Between Calibration and Verification

1. Different purposes

verification - a mandatory comprehensive evaluation of the measurement characteristics. Uniformity of values and compliance of the test with the specified requirements. Top-down transfer of values.

Calibration - self determination of the accuracy of monitoring and measuring devices. Is the bottom-up traceability of the measurement value, assessment of the display value error.

Comment: Accreditation, the key is to compare with the measurement standard to determine whether it meets the statutory requirements. Calibration, compared with the measurement standard, to give "measured value ± extended uncertainty".

2. Different objects

Verification - the national compulsory verification: measurement reference apparatus; measurement standards; for trade settlement, safety and security, medical and health, environmental monitoring of the work of measuring instruments a total of 59 kinds.

Calibration - in addition to the mandatory verification of measuring instruments and measuring devices.

Comment: The object of inspection is, included in the national legal management of measuring instruments catalog of measuring instruments. This includes part of the mandatory verification of measuring instruments. Calibration of the object is, selectively, you can choose to do calibration of non-compulsory verification of measuring instruments.

3. Based on different

Verification - by the state authorized by the measurement of the unified development of the verification procedures.

Calibration - calibration specifications or calibration methods, can be used by the state unified regulations, or by the organization's own development.

Comment: The calibration specification prepared by oneself must be approved by the competent authority (or administrative approval of the organization).

4. Different properties

Verification - mandatory, is the legal measurement of the scope of management of law enforcement.

Calibration - not mandatory, voluntary traceability of the organization.

5. Different cycles

Verification - in accordance with the mandatory testing cycle prescribed by law in China to implement.

Calibration - by the organization according to the use of the need to determine their own, can be regular, irregular or before use.

6. Different methods

Verification - only in the provisions of the calibration department or by the statutory authorization of qualified organizations.

Calibration - can be self-calibration, external school or self-calibration and external school combination.

7. Different contents

Verification - the measurement of the characteristics of the *** assessment, including the assessment of the value of the error.

Calibration - assessment of the error in the display value.

Note: The error can be calculated according to the measured value - standard value, but the error can not be assessed.

Calibration consists of comparing the displayed value of the calibrated instrument with the standard value to obtain the actual value or error or correction value or correction curve or correction value graph or correction value table. The actual or corrected values should be accompanied by a measurement uncertainty value.

8. Different conclusions

Verification - based on the range of error in the value of the test specification, to give a qualified and unqualified judgment, issued by the certificate of conformity.

Calibration - not to determine whether qualified, only assess the error in the indicated value, issued by the calibration certificate or calibration report.

Comment: test failed to issue a notice of test results.

Calibration generally do not do conformity assessment, unless there is a written contract with the customer can do to pass the judgment, the need to do conformity judgment must be based on what the first few terms of the document (not necessarily product specifications or test procedures, including the customer to provide the measurement of the production process requirements).

9. Different legal effects

Verification - calibration conclusions are legally binding documents, as measuring instruments or measuring devices calibration of the legal basis.

Calibration - calibration conclusions are not legally binding technical documents.

Comment: Accreditation conclusions can be used as a legal basis for qualified or not. Calibration results do not have legal effect.