World Metrology Day 2018


World Metrology Day is an annual celebration of the signature of the Metre Convention on 20 May 1875. The Metre Convention is the basis for worldwide cooperation in the field of metrology. The International System of Units, todays authoritative basis for measurement all over the world, is based upon the Metre Convention. 

Fundamental revision of the International System of Units (SI)

It is expected that in November 2018 a fundamental revision of the International System of Units will be approved. The revised SI is based on seven precisely defined physical constants. Starting from these constants, all the units making up the system, both base units as well as derived units, can be construed with the aid of physical laws. This also applies to the unit of mass, the kilogram, which is still defined today though a material measure, the international prototype kilogram in Paris. This fundamental revision will not have an influence for evereyday live: a kilogram will remain a kilogram.

Last modification 19.02.2019

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