Resolution 7 of the 21st CGPM (1999)

The definition of the kilogram

The 21st Conférence Générale des Poids et Mesures,

considering

• the need to assure the long-term stability of the SI,
• the intrinsic uncertainty in the long-term stability of the artefact defining the unit of mass, one of the base units of the SI,
• the consequent uncertainty in the long-term stability of the other three base units of the SI that depend on the kilogram, namely, the ampere, the mole and the candela,
• the progress already made in a number of different experiments designed to link the unit of mass to fundamental or atomic constants,
• the desirability of having more than one method of making such a link,

recommends that national laboratories continue their efforts to refine experiments that link the unit of mass to fundamental or atomic constants with a view to a future redefinition of the kilogram.

DOI : 10.59161/CGPM1999RES7E