Abstract. This article describes the results of the first COOMET key comparison in which four national metrology institutes (NMIs) took part. Three samples of Newtonian liquids with nominal kinematic viscosities of 30 mm²/s, 100 mm²/s and 1000 mm²/s at 20 °C were used to determine the degrees of equivalence of the national standards of Belarus, Ukraine and Bulgaria to the standards of NMIs that took part in the KC CIPM (CCM.V-K1).

The results of the evaluation of data obtained for all liquids used in the comparison were compared with the reference values (KCRV), obtained in the first key comparison CIPM (CCM.V-K1).

Main text. To reach the main text of this Paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.

The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).