Traceability

General provisions

The laboratory ensures measurement consistency with reference standards of the Central Office of Measures and accredited national and foreign laboratories. Measurement uncertainty is determined with probability of expansion of approximately 95% under accepted conditions. Calibration results include the size of the underlying error and the uncertainty of the result.

Traceability

Equipment used for testing and calibration (control and utility meters) shall be calibrated before putting it into use to ensure connection with the SI International Units System. Equipment supervision is based on internal Laboratory procedures. Records of the surveillance performed are recorded in the equipment catalogs.

Calibration is performed by selected accredited laboratories, GUM and laboratories of leading manufacturers of measuring equipment. Condition of recognition of the manufacturer's certificates is that they are accredited for compliance with the international standard EN ISO / IEC 17025 and that the certificate must bear the sign of a laboratory accredited with reference to the standard.

Estimation of uncertainty

The Laboratory applies the guidance of the document EA-4/02 M:2021 for measuring uncertainty and measuring capacity (CMC) for the calibration methods used. Statistical methods are used to calculate calibration uncertainty and CMC. Calibration uncertainty is presented in calibration certificates, as recommended by EA-4/02 M: 2021, in the form of extended uncertainty with an expansion probability of approximately 95%.

Each calibration manual developed and used in the Laboratory has a point for estimating measurement uncertainty and an attachment for designation CMC with calculations for the calibration method used.



Calibration range