Comparison for gas flow range 5 ml/min to 30 l/min (EURAMET.M.FF-S10)

The EURAMET.M.FF-S10 comparison, also registered as EURAMET project 1325, was organized to compare the results of low gas flow facilities at twelve European laboratories. The following laboratories took part in the comparison: MIKES (Finland), INRIM (Italy), PTB (Germany), FORCE (Denmark), METAS (Switzerland), VSL (Netherlands), EIM (Greece), UL (Slovenia), CMI (Czech Republic), LNE (France), GUM (Poland), LEI (Lithuania). Due to the high amount of participants, the comparison was carried out in two parallel loops with one circulating transfer standard in each loop. MIKES acted as the pilot laboratory and INRIM and PTB were the linking laboratories. High-accuracy piston provers (MesaLabs DryCal 800) provided by Mesa Laboratories Inc. were used as transfer standards. Each transfer standard package consisted of three flow cells in order to cover the flow range of the comparison from 5 ml/min to 30 l/min. Generally, a good agreement between participating laboratories was found; 85% of the results agree with the comparison reference value and only 8% were found inconsistent. The remaining 7% of results were classified as inconclusive, because the participating laboratory stated uncertainty was lower than the standard uncertainty of the transfer standard. The comparison provided valuable experience of using piston provers as high precision transfer standards. Such an extensive inter-comparison using piston provers has not been done before. As such, it gives a good overview on the capabilities of European laboratories of calibrating such instruments that are commonly used in industrial calibration laboratories worldwide. 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 (CIPM MRA).