Knowledge
Metrology Dictionary
The complete VIM vocabulary — all numbered concepts of JCGM 200:2012 as faithful paraphrases with clause citations — plus clearly labeled practice terms from the GUM, ILAC, ISO and NIST guidance.
Air buoyancy correction
The correction applied in precise mass comparisons for the differing volumes of the standards and the object weighed, proportional to air density and volume difference — dominant in high-accuracy mass work.
NIST SOP 2 / OIML R 111 · Mass
Conventional mass
The conventional value of the result of weighing in air, based on a reference density of 8000 kg/m³ for the weight and 1.2 kg/m³ for air at 20 °C — the basis on which standard weights are specified per OIML R 111.
OIML R 111-1:2004 · Mass