Metrological Traceability at Different Measurement Levels

Abstract

The international agreements are the basis for establishing the global metrological traceability at different measurement levels. The concepts and concept relations around metrological traceability are presented. An important element of providing the metrological traceability is the evaluation of measurement uncertainty. The procedure of linking of key and supplementary comparison results is described. Linking of key and supplementary comparison results of the Regional Metrology Organization for some quantities according to the described procedure was presented. Results for all participants of presented key and supplementary comparisons are satisfactory for chi-square test and E n number. The procedure of linking of key or supplementary comparison and national inter-laboratory comparison results is described. This procedure can be used for practical evaluation of specific interlaboratory comparison results on a national level in different countries by means of laboratory results of the National Metrology Institute and Designated Institute. This procedure can contribute the mutual recognition of measurement and testing results by different countries. Linking of key comparison and inter-laboratory comparison results for some quantities according to the described procedure was presented. Results for all participants of presented key comparison and interlaboratory comparison are satisfactory for chi-square test, E n number, z scores and ζ scores.

The Data Evaluation of Interlaboratory Comparisons for Calibration Laboratories

“…A program for all ILCs was implemented in accordance with the requirements of ISO/IEC 17043 [15]. CLs that participated in the ILCs performed calibration of the measuring instruments (calibration object) provided to the RL in accordance with their own methods according to the radial scheme [4]. RL sent the calibration object to the participating laboratory, and this laboratory returned this object back to RL.…”

“…The data obtained from CLs were necessarily checked by RL for their consistency. Indicators for assessing of consistency were E n and z indexes set and defined in [4,15]. The general algorithm of processing of the received primary data of ILCs given in [34] was used.…”

“…During of the evaluation of primary data from the participating CLs, the interlaboratory deviation of the measurement results or degree of equivalences (DoE) was calculated based on the ILCs results. The DoE for j-th CLs participant of ILC is calculated using Equation [4,34,38].…”

“…Participants in the International Laboratory Accreditation Cooperation (ILAC) Mutual Recognition Agreement (MRA) recognize the calibration or test results obtained by each other's accredited calibration and testing laboratories [1][2][3][4]. ILAC Policy and Procedural publications are for the operation of the ILAC MRA.…”

Traceability Features of the Electric Power Unit in Ukraine

“…MT at the highest metrological level is carried out through participation in international comparisons of the national standards of NMI or DI. In such case MT at lower measurement level is carried out through the calibration procedures of working standards by both NMIs or DIs and accredited CLs [8].…”