What is the difference between calibration and verification in metrology

To put it simply, calibration is self-traceable, and verification is forced value transfer.

Verification and calibration

Verification: refers to the evaluation of measuring instruments.

The measurement performance of the company, to determine whether it is qualified or not, all the work carried out, including inspection and sealing, etc.

Calibration definition: A set of operations to determine the relationship between a quantity indicated by a measuring instrument or measuring system, or a value represented by a physical gauge or reference material, and the corresponding quantity reproduced by a standard, under specified conditions.

"Calibration" and "verification" are two different ways and means to ensure the accuracy and effectiveness of the value. Calibration and verification are the same in terms of value traceability, but they are different in terms of legal effect.

Clause A) in the GJB9001A-2001 standard requires: Compare with the measurement standards that can be traced back to international or national standards, if necessary, the measuring equipment should be calibrated or verified according to the specified time interval or before use.

The word "or" in the standard determines the juxtaposition and selectability between calibration and verification. in compliance with laws and regulations.

Under the premise, enterprises and institutions can choose their own verification or calibration methods for different situations.

Similarities and differences:

The similarity between verification and calibration is that they are both an effective and reasonable method and means for the traceability of the value, and the purpose is to achieve the traceability of the value. The difference between the two is:

1.Verification is a comprehensive evaluation of the metrological characteristics of measuring instruments; Calibration, on the other hand, is mainly used to determine its magnitude.

2.The verification should make a conclusion on whether the measuring instrument is qualified or not; Calibration does not determine whether the measuring instrument is qualified or not.

3.The verification shall be issued with a verification certificate, a verification mark or a notice of disqualification; Whereas, calibration is the issuance of a calibration certificate or calibration report.

4.The verification is based on the metrological verification procedures; The calibration is based on the calibration specifications.

The main differences between calibration and verification are:

1. Different objects - the object of verification is the measuring instrument of compulsory verification clearly stipulated in the "Metrology Law", and the object of calibration is the measuring instrument that belongs to the compulsory verification.

2. Different purposes - the purpose of verification is to carry out mandatory comprehensive evaluation of measuring instruments, and the purpose of calibration is to evaluate the indication error of measuring instruments against measurement standards to ensure the accuracy of the measurement value.

3. According to different - the verification is based on the verification regulations, and the measurement verification regulations refer to the technical provisions on the verification cycle, measurement characteristics, verification items, verification conditions, verification methods and verification data processing of measuring instruments. The calibration is based on the calibration specification, which can be carried out with reference to the verification procedures, or the calibration method can be determined by the calibration party and the user by agreement.

4. Different methods: verification can only be carried out in legal metrology and testing institutions or authorized qualified institutions, and calibration can be carried out in a combination of self-calibration, external school or self-external school.

5. The nature is different: verification is mandatory, and calibration is not mandatory.

6. The validity period is different: the validity period is required on the verification certificate. Calibration certificates generally do not give an expiration date.

7. Different legal effects: the conclusion of the verification has legal effect, and the verification certificate is a technical document with legal effect. The conclusion of the calibration has no legal effect, and the calibration certificate given only indicates the error of the measurement value, which is a technical document.

8. The conclusion is different: the verification must be based on the error range of the quantity specified in the "Verification Regulations", and the judgment of passing and failing must be given. The calibration result is usually a calibration certificate or calibration report, and there is no need to give a pass or fail decision.

The difference between verification and calibration is that the purpose, object, nature, basis, method, period, content and other seven aspects are different.

1. The purpose is different.

Calibration is mainly used to determine the indication error of the measuring instrument.

Verification is a comprehensive evaluation of the metrological performance of measuring instruments to determine whether they are qualified.

2. The objects are different.

The object of calibration is the measuring instrument other than the mandatory verification.

The object of verification is the measuring instrument that is clearly stipulated in the measurement law of our country.

3. The nature is different.

Calibration is not mandatory, and it is a voluntary traceability behavior of the unit.

The verification is mandatory and belongs to the scope of legal measurement management.

4. The basis is different.

The calibration is based on the "Calibration Specification" formulated by the laboratory according to the actual needs, or with reference to the requirements of the "Verification Regulations" and other technical documents.

The basis of the verification is the "Metrological Verification Regulations", which is a technical regulatory document that must be followed for metrological verification.

5. Different ways.

The calibration can be carried out by laboratory self-calibration, external calibration, or a combination of self-calibration and external calibration.

The verification must be carried out by a legal metrology verification body, or an authorized metrological verification body.

6. The cycle is different.

The calibration interval is determined by the laboratory itself according to the needs of the measuring instrument used.

The verification cycle must be determined by the metrological verification institution that undertakes the verification work in accordance with the provisions of the "Verification Regulations", and the verification cycle is a mandatory constraint.

7. The content is different.

The content and items of calibration are only to evaluate the indication error of the measuring instrument to ensure the accuracy of the measurement.

The content of the verification is to comprehensively evaluate the measurement performance of the measuring instrument to ensure that the measuring instrument is qualified and effective.

1. The purpose is different.

Calibration: Determine whether the measurement value of the monitoring and measuring device is accurate, which is the bottom-up traceability of the value and evaluate the indication error.

Verification: Mandatory comprehensive evaluation of measurement characteristics, whether it meets the specified requirements, is a top-down value transmission.

2. The cycle is different.

Calibration: Determined by the organization according to the needs of use, and can be performed periodically, irregularly, or before use.

Verification: It is implemented according to the mandatory verification cycle stipulated by the laws of our country.

3. The content is different.

Calibration: Evaluate the indication error.

Verification: A comprehensive evaluation of the metrological characteristics, including the evaluation of the error of the value.

4. Different ways.

Calibration: It can be self-calibrating, external calibration, or a combination of self-calibration and external calibration.

Accreditation: It can only be carried out in a prescribed appraisal department or in a legally authorized and qualified organization.

5. The conclusions are different.

Calibration: It does not determine whether it is qualified or not, only evaluates the indication error, and issues a calibration certificate or calibration report.

Verification: According to the error range of the quantity specified in the regulations, the judgment of passing and unqualified is given, and the verification certificate is issued.

The difference between "verification" and "calibration" is: 1. Different purposes of calibration: the purpose of calibration is to evaluate the indication error of the measuring device against the measurement standard to ensure the accuracy of the value, which belongs to a group of operations that trace the value from the bottom up.

Verification: The purpose of verification is to carry out a mandatory comprehensive assessment of the measuring device. This kind of comprehensive assessment belongs to the category of value unification, which is a top-down value transfer process.

2. Different objects are calibrated: the objects of calibration are measuring devices that belong to the mandatory verification. The measuring devices for non-compulsory verification in China mainly refer to the measuring instruments used in a large number of production and service provision processes, including the measuring instruments used in incoming inspection, process inspection and final product inspection.

Verification: The object of verification is the measurement device for compulsory verification clearly stipulated in China's metrology law. 3. Calibrations with different properties

Calibration is not mandatory, it is a voluntary traceability behavior of the organization. This is a kind of technical activity, which can evaluate the indication error of measuring instruments according to the actual needs of the organization, and determine the process of determining the value of measuring instruments or reference materials. Organizations can prescribe calibration specifications or calibration methods based on actual needs.

Define calibration cycles, calibration markings, records, etc. Verification: Verification is a mandatory law enforcement act and belongs to the legal measurement management.

The difference between the two

First, the purpose is different.

Verification – a mandatory comprehensive assessment of metrological characteristics. The value of the genus is unified, and whether it meets the specified requirements is verified. Top-down transmission of quantities.

Calibration – Determine the accuracy of the monitoring and measuring device measurements yourself. It is a bottom-up value traceability and evaluation of the indication error.

Second, the object is different.

Verification - National Compulsory Verification: Measurement Reference Instrument; Metrological standards; It is used as a working measuring instrument for settlement, safety protection, medical and health care, and environmental monitoring.

There are 59 species in total. Calibration – measuring instruments and measuring devices other than mandatory verification.

Third, the basis is different.

Verification - the verification procedures uniformly formulated by the measurement department authorized by the state.

Calibration – Calibration specifications or calibration methods, which can be uniformly prescribed by the state or developed by the organization itself.

Fourth, the nature is different.

Verification - a mandatory law enforcement act within the scope of legal measurement management.

Calibration - not mandatory, it is a voluntary traceability behavior of the organization.

Fifth, the cycle is different.

Verification: It is implemented according to the mandatory verification cycle stipulated by the laws of our country.

Calibration: Determined by the organization according to the needs of use, and can be performed periodically, irregularly, or before use.

Sixth, the way is different.

Accreditation – may only be conducted in a prescribed accreditation department or in a qualified organization authorized by the Legal-Lee-Critical Accreditation Department.

Calibration: It can be self-calibrating, external calibration, or a combination of self-calibration and external calibration.

Seventh, Nathan is different.

Verification: A comprehensive evaluation of the metrological characteristics, including the evaluation of the error of the value.

Calibration: Evaluate the indication error.

8. The conclusions are different.

Verification - according to the error range of the quantity specified in the verification regulations, the judgment of pass and failure is given, and the verification certificate is issued. Calibration: It does not determine whether it is qualified or not, only evaluates the indication error, and issues a calibration certificate or calibration report.

9. The legal effect is different.

Verification - The verification conclusion is a legally valid document and serves as the legal basis for the verification of measuring instruments or measuring devices.

Calibration - The calibration conclusion is a technical scrambled document with no legal effect.

Calibration and verification are explained below:

1) Danji verification: the full name of the verification of measuring instruments or the verification of testing instruments, referred to as metrological verification or verification, refers to "the identification and confirmation of measuring instruments in accordance with the statutory requirements of the activities, it includes inspection, marking and or issuance of verification certificates." ”

2) Calibration: a set of operations under specified conditions, the first step is to determine the relationship between the quantity value provided by the measurement standard and the corresponding indication value, and the second step is to use this information to determine the relationship between the measurement result obtained by the indication template socks, where the measurement standard provides the quantity value and the corresponding indication value have uncertainty.

3) Testing: For a given product, in accordance with the prescribed procedures to determine one or more characteristics, processing or providing services composed of technical operations.

"Calibration" and "verification" are two different ways and means to ensure the accuracy and effectiveness of the value. Calibration and verification are the same in terms of value traceability, but they are different in terms of legal effect. Clause A) in the GJB9001A-2001 standard requires:

Measurement equipment should be calibrated or verified at specified intervals or prior to use, if necessary, against measurement standards that can be traced to international or national standards. The word "or" in the standard determines the juxtaposition and selectability between calibration and verification. Under the premise of meeting laws and regulations, enterprises and institutions can choose their own verification or calibration methods for different situations.

Calibration is a voluntary traceability behavior of enterprises and institutions, not mandatory, enterprises and institutions can be calibrated on their own, or they can be commissioned, generally not legally effective technical documents. The verification is a mandatory law enforcement act of the state, the verification results must be submitted to the measuring instruments, instruments and equipment to make a judgment of whether they are qualified or not, when the results are qualified, the verification certificate will be issued, and the unqualified notice will be issued, and the verification results have legal effect. Measuring instruments that are subject to mandatory verification must meet two conditions at the same time:

First, the instrument is included in the catalogue of working measuring instruments for compulsory verification by the state; Second, the measuring instrument must be used for specific purposes such as settlement, safety protection, medical and health care, and environmental testing. Measuring instruments used for settlement, safety protection, medical and health, and environmental testing purposes, such as measuring instruments used in scientific research, production, and business management, can generally be managed and controlled in accordance with non-compulsory verification of measuring instruments.

CLP metering and testing, instrument calibration, providing door-to-door on-site testing, calibration and testing centers in each city, and the quasi-certificate of the school file family meets the requirements of ISO, UL, 3C, CQC, CE and customer factory audit.

Calibration is not legal, it is a voluntary traceability behavior of enterprises; The verification rules are legal and belong to the implementation of the scope of measurement management; Calibration mainly determines the indication error of the measuring instrument; The verification is a comprehensive assessment of the compliance of its metrological characteristics and technical requirements; The basis of calibration is calibration specifications and calibration methods, which are usually uniformly specified and sometimes can be formulated by themselves; The basis of the verification is the verification procedure; Calibration usually does not judge whether the measuring instrument is qualified or not, and if necessary, it can also determine whether the performance of a certain skin barrier meets the expected requirements; The verification must make a conclusion of whether it is qualified or not; The results of the calibration are usually issued with a calibration certificate or a calibration report; The verification result is that the qualified certificate will be issued, and the unqualified will be issued a notice of disqualification.