THE INTERNATIONAL WORLD REFERENCE VALUE FOR HIGH PRESSURE NATURAL GAS FLOW AS APPROVED BY CIPM KEY COMPARISONS

Key words: flow measurement, calibration of gas meters, international reference value, BIPM-CIPM Key comparisons, world reference value for natural gas flow measurements Harmonized Reference Value, Harmonized European Gas Cubic Meter. Under auspices of the BIPM (International Bureau for Weight and Measures) as well as the CIPM (International Conference for Weight and Measures), which is the highest metrological authority worldwide, so called Key Comparisons (KC) have been conducted to get international reference values for all quantities of interest. Among these KCs, the flow area is of economic importance and Key Comparisons for natural gas flow at high pressure and larger flow rates as well as for compressed air have been conducted successfully among all interested National Metrology Institutes. The outcome of such a KC is the international Key Comparisons Reference Value (KCRV), which is then considered to be the worldwide best available realization of Natural Gas Flow at high pressure. (World Reference Value). These KCs have been conducted among the National Primary Standards of all nation