Creating a calibration chain for measuring instruments using relational database

One of the indicators of measurement quality is metrological traceability, which is represented in the form of calibration chains, that are documented sequences of calibration results from the working measuring instrument to the measurement standards with the highest accuracy. Based on conducted analysis, it is proposed to present calibration chains not linearly but as branched acyclic directed graphs. The aim of the study is to find a solution for calibration data storage and calibration chain creation for a particular measuring instrument using stored calibration data to ensure metrological traceability in a simple way. To store the information about measuring instruments and their calibrations, relational databases are proposed to be used. They provide consistent data and allow obtaining historical data about calibrations. In addition, an algorithm to create documented calibration chains for branched traceability chains is proposed. The practical value of the study lies in the development of a software product for measuring instruments of gas volume and volumetric gas flow rate. The software application will give the possibility to metrological centre “Ivano-Frankivskstandartmetrology” to keep consistent calibration data and to ensure metrological traceability for particular measuring instruments to the national measurement standards.