Guide to the Expression of Uncertainty in Measurement (GUM) and "mutual recognition of national measurement standards and of calibration and measurement certificates issued by national metrology institutes" (MRA): Some problems of data processing and measurement uncertainty evaluation

In the present report the outcomes of discussion of the concept of the measurement uncertainty in Russia are represented, the opinion of the authors on the given problem is expressed, the ways of application of Guide to the Expression of Uncertainty in Measurement (GUM) in Russia are demonstrated, The concept of the equivalence of the measurement standards, its place in a traceability system of measurements throughout the world, tasks of key-comparisons and quantitative estimators of degrees of equivalence of the measurement standards are considered. The common problems of the procedure for performing measurements at key comparisons are discussed.