Konopelko L.A.,Di Mendeleyev Institute For Metrology Vniim |
Kustikov Y.A.,Di Mendeleyev Institute For Metrology Vniim |
Kolobova A.V.,Di Mendeleyev Institute For Metrology Vniim |
Pankratov V.V.,Di Mendeleyev Institute For Metrology Vniim |
And 9 more authors.
Metrologia | Year: 2014
A comparison was proposed in 2011 within the cooperation program in the field of metrology between VNIIM and INMETRO. In 2012 it was registered as COOMET regional comparison. The objective of present preparative comparison is demonstration of each NMI's capability in GRAVIMETRIC PRODUCTION OF PRIMARY STANDARD GAS MIXTURE (PSM) OF METHANE IN SYNTHETIC AIR in the concentration range 10 to 1000 ?mol/mol. The participants prepared gas mixtures for the comparison gravimetrically in accordance with requirements of ISO 6142  and studied regarding their composition and stability in accordance with requirements of ISO 6143. Inmetro prepared 1 PSM of methane in synthetic air on the level of 100 ?mol/mol, carried out verification measurements against 3 calibration standards, produced by VSL, with certified values in the range 30 to 150 μmol/mol. The measurement protocol requested each laboratory to perform at least 3 measurements obtained under repeatability conditions including at least three separate calibrations. VNIIM prepared 3 primary gas mixtures (?H4/synt air). All of them had nominally similar methane mole fraction on the level of 100 ?mol/mol. Inmetro and VNIIM PSMs for methane in synthetic air (100 μ mol/mol) are in a good agreement, the pair-wise degree of equivalence is substantially smaller than its expanded uncertainty.