Most of the national mass standard laboratories perform volume (density) determinations of their sets of mass standards by hydrostatic weighing. There is a need to assess the uncertainty of the volume determination of the mass standards because of its important contribution to the uncertainty of the mass standard itself.
The aim of this project is to intercompare the volume determination by checking the compatibility of the measured volume values through the calibration of one or more transfer standards by hydrostatic weighing.
The transfer standards will be spheres made of ceramic material (Si3N4_MgO). They will be carefully selected and monitored at regular intervals by the pilot laboratory before and during the intercomparison.
Three spheres will be available for the intercomparison with the following approximate data:
|1 kg||316 cm^3||85 mm|
|700 g||221 cm^3||75 mm|
|277 g||88 cm^3||55 mm|
The comparison was completed and published in the KCDB.