EN
Verification and calibration of measuring instruments
Verification of measuring instruments is a set of operations performed by the bodies of the State Metrological Service (other bodies and organizations authorized to do so) in order to confirm the compliance of the measuring instrument with established metrological requirements.
Verification is necessary to determine whether the characteristics of a measuring instrument comply with the specified values and are suitable for use for its intended purpose.
All measuring instruments of the approved type are subject to verification. The actual users of the measuring instrument (legal entities and individuals) are responsible for the timely provision of the measuring instrument for verification.
Verification of measuring instruments is performed at the stages of release from production, after repair and during operation. There are the following types of verification of measuring instruments :
- Primary. Verification is performed when a new copy of the measuring instrument is put into operation or after repair.
- Periodic. It is carried out during the operation period in accordance with the regulated inter-verification intervals (IVI) : upon commissioning after storage, if the storage period exceeds the IVI.
- Extraordinary. This verification is carried out in the event of compliance of the verification mark with the form established in the Procedure for Verification of Measuring Instruments, as well as damage to the verification mark or seal.
The inter-verification interval for each type of measuring instrument is established by the State Center for Testing of Measuring Instruments during testing for the purpose of type approval and is indicated in the description of the measuring instrument type.
Verification of measuring instruments can be carried out by:
- State Scientific Metrology Centers (SSMC)
- Regional centers of metrology, standardization and certification (CSM)
- Legal entities and individuals, accredited in accordance with the established procedure
- Verification and control points based on enterprises engaged in the production and/or repair of measuring instruments.
The verification results are certified:
- verification mark
- verification certificate,
- an entry in the measuring instrument passport (form), certified by the signature of the verifier and the verification mark.
The design of the measuring instrument must provide the possibility of applying the verification mark in a place accessible for viewing. If the design features or operating conditions of the measuring instrument do not allow the verification mark to be applied directly to the measuring instrument, the verification mark may be applied to the verification certificate or to the passport (form).
If, based on the verification results, the measuring instrument is deemed unsuitable for further use, the previous verification certificate is cancelled and a notice of unsuitability in the established form is issued.
Calibration of measuring instruments.
Calibration of measuring instruments is a set of operations performed to determine the actual values of the metrological characteristics of the measuring instrument.
The calibration results allow us to determine:
- actual values of the measured quantity;
- correction to the readings of the measuring instrument;
- SI error.
If the equipment is not included in the State Register of Measuring Instruments, then it is subject to calibration, not verification.
The difference between verification and calibration.
Only an accredited laboratory can perform the verification procedure and issue the corresponding certificate, and the measuring instrument itself must be within the scope of its accreditation.
This is not required for the calibration procedure. It can be performed by any laboratory that has the appropriate equipment for measuring the required characteristics.
Another important difference is the following - during calibration, there is no task to check whether the obtained values meet the requirements of anything. The document mainly indicates only the obtained metrological data, without specifying the compliance with the class, GOST, TU, etc.
