Development of Reference Materials of Specific Electrical Conductivity of Liquids

Specific electrical conductivity is one of the most important indicators of water quality in technological processes of microelectronics production, pharmaceutics, thermal and nuclear power engineering; the indicator studied during environmental monitoring. Based on accurate data on specific electrical conductivity of liquid, it is possible to reliably assess the state of production systems and technological processes. The article describes a study conducted to develop and produce two types of reference materials of specific electrical conductivity of liquid – SEC‑10 (GSO 12746-2024) and SEC‑20 (GSO 12374-2023). The article presents the materials and instruments used in the production of reference materials. An assessment of the relative uncertainty of certified values of long-term and short-term stability is given, calculations of the relative expanded uncertainty of certified values of reference materials are presented in accordance with GOST ISO Guide 35–2015. In the course of the work, the metrological traceability of the certified values of reference materials to the measurements unit of “specific electrical conductivity” reproduced by State Primary Standard of the unit of specific electrical conductivity of liquids in the range from 0,001 to 50 S/m GET 132‑2018 was established. The developed reference materials were added to the list of available domestic reference materials due to the increased range of specific electrical conductivity values, which is from 1 to 20 S/m. Market availability will allow new reference materials to replace imported analogues, thereby reducing the time and cost of metrological work. The article is addressed to state metrology centers performing verification, calibration and testing for approval of the type of conductometric analyzers. The publication may be useful for organizations conducting scientific research and metrology services of enterprises of various industries.