Linking of rounds results of interlaboratory comparisons on calibration of electrical resistance measures on a direct current

Abstract

Interlaboratory comparisons (ILC) are used to evaluate and confirm measurements’ accuracy, reliability, and reproducibility. ILCs are conducted for both testing and calibration laboratories (CL). They are comparing the results of measurements or calibrations obtained by different laboratories. The main stages of confirming the competence of laboratories include accreditation as the first step of such confirmation, as well as periodic participation in the ILCs. This is the basis for confirmation of the competence of laboratories and contributes to increasing confidence in the data obtained in these laboratories. The proposed approach to linking the results obtained by the laboratories in different rounds made it possible to jointly evaluate the CL results of two rounds of the ILC on the calibration of measures of electrical resistance on direct current. This provided confirmation of the competence of a larger number of CLs in the calibration of resistance measures. This approach can be applied to the evaluation of the laboratory results and a larger number of ILC rounds, but under the condition that the same CL is chosen as the reference laboratory. The majority of CLs, which participated in two rounds of the ILC for the calibration of resistance measures of nominal values of 1 Ω, 10 Ω, 100 Ω, received positive evaluation results using a modified criterion based on functioning statistics – the En number. They have confirmed their qualification in performing calibration for this measurand in accordance with the requirements of ISO/IEC 17025 standard. Several CLs do not meet the requirements for the value of En, so they need to implement the necessary corrective measures.