Ensuring metrological traceability of reference gas mixture composition materials
摘要
The modern concept of metrological assurance of the analytical gas-measuring instruments is presented based on the use of reference gas mixture composition materials in pressurized tanks. These reference materials are most commonly used during analytical gas measurements as the means for transferring units of mole fraction and mass concentration of the components in gaseous and gas-condensate media. In the reference materials, the content of the target component(s) in the gaseous medium (analytical matrix) is certified. To ensure the uniformity of analytical gas measurements, all produced reference gas mixture composition materials are traced to the State primary standard of units of mole fraction, mass fraction, and mass concentration of the components in gaseous and gas-condensate media (GET 154-2019). A procedure for ensuring metrological traceability of the reference gas mixture composition materials with the use of GET 154-2019 is presented, which accounts for the constantly increasing pool of analytical gas-measuring instruments and for the emergence of new measuring tasks in various industry sectors and areas of environmental control. Currently, a pool of secondary and work standards has been created at the enterprises that produce reference gas mixture composition materials, and the traceability of such materials to GET 154-2019 has been implemented according to the state verification schedule. It was shown that the variety and multitude of the actual measurement tasks involving gas analysis in various industrial sectors and social sphere determine the need for prioritizing directions for improving the existing base of reference materials, including the composition of the GET 154-2019 standard and the range of the reference gas mixtures. The strategic program, developed for the period up to 2030 by the Working Group on Gas Analysis of the Consultative Committee for Amount of Substance of the International Bureau of Weights and Measures, has been analyzed, and a review of the long-term tasks of analytical gas measurements was performed. The currently utilized latest-generation GET 154-2019 standard ensures reproduction, storage, and transfer of the units of mole fraction and mass concentration of the components in gaseous and gas-condensate media ranging from 1.5 · 10−8 to 99.99999% and from 1.0 · 10−6 to 2.0 · 105 mg/m3, respectively. The GET 154-2019 characteristics have been confirmed by the results of participation in about 90 comparisons. The results of these international comparisons are provided, which confirm the comparability of the obtained and reference values of the target component content in gaseous mixtures. The calibration and measurement capability database of the International Bureau of Weights and Measures has published about 400 positions related to analytical gas measurements.