Final Report "The comparison of national standards of the sound pressure unit in air through calibration of working standard microphones"

Abstract

The supplementary comparison COOMET.AUV.A-S2 for secondary calibration methods using WS1 and WS2 measurement microphones was carried out from 2014 to 2015. The results were submitted to and approved by CCAUV in September 2018.Four National Metrological Institutes which took part in this comparison are as follows: (BelGIM (Belarus), VNIIFTRI (Russia) and DP NDI "Sistema" (Ukraine)). Two of the above NMIs (VNIIFTRI and DP NDI "Sistema") had earlier participated in the COOMET key comparison and one NMI (VNIIFTRI) had also participated in CCAUV key comparison.The Comparison Reference Values were calculated as the weighted mean values from results obtained by two institutes. The comparison results showed agreement for all participants in the frequency range from 20 Hz to 10 kHz for WS1 microphones and in the frequency range from 20 Hz to 20 kHz for WS2 microphones.The obtained results confirm the uncertainties of the electrostatic sensitivity measurement level for inch and half-inch working standard microphones Types WS1P and WS2P respectively.KEY WORDS FOR SEARCHacoustics, supplementary comparison, standard microphone, electrostatic sensitivity mesurement levelMain textTo 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 CCAUV, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).