State primary standard of unit of the mass concentration of oxygen, hydrogen and carbon dioxide in liquid media GET 212-2023

Abstract

The accuracy of measurements of the mass concentration of dissolved carbon dioxide and the requirements for the accuracy of such measurements, namely, the relative error of measurements of the mass concentration of carbon dioxide (about 10 %) at the enterprises of the Russian industry are investigated. The issues of ensuring the uniformity of measurements and achieving metrological traceability of the measurement results of the mass concentration of carbon dioxide in liquid media to the state primary standard are considered. The State primary standard of units of mass concentration of oxygen, hydrogen and carbon dioxide in liquid media GET 212-2023 is described. The GET 212-2023 includes new technical means: systems of gas supply and gas mixing of carbon dioxide, measurement system of dissolved carbon dioxide. Gas supply and gas mixing systems implement the reproduction method. A software-controlled measuring system is used to measure the mass concentration of dissolved carbon dioxide. A method of reproducing the unit of mass concentration of dissolved carbon dioxide based on the Henry-Dalton law is described. The results of studies of metrological characteristics of GET 212-2023 are presented. For the fi rst time, the fundamental possibility of reproducing the unit of mass concentration of dissolved carbon dioxide in the range from 0 to 15 g/dm3 with a relative non-excluded systematic error not exceeding 2.5% has been achieved in the Russian Federation. GET 212-2023 will ensure current requirements in various industries, such as food, pharmaceutical and chemical, as well as in the fi eld of environmental protection, electronics and semiconductor technologies.