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– and to ensure the coherence of national standards.
The Convention adopted French as its official language.
The international level
In addition, the BIPM (International Bureau of Weights and
Measures) was intended to improve the processes of comparison and
transfer between standards. Once the aims of the BIPM were
established, all that was needed was a venue. On 22nd April 1876, the
French government set the former Breteuil pavilion at the disposal of
the Comité International des Poids et Mesures. The pavilion was
situated at the heart of the Saint Cloud park, far away from any
sources of vibration, and was a 4 hectare international enclave in
French territory.
The BIPM
Today, at the beginning of the 21st century, the BIPM continues
to attend to the standardization of physical measurements in the world.
Its scientific activity aside, the BIPM is certainly the oldest
establishment that “standardizes”; it is indeed possible to consider the
SI as the oldest published document of international harmonization.
The BIPM, together with the national metrology institutes, are
responsible for the SI (Systems of Units), which is the key to the
uniformity of measurements internationally and one of the
unquestionable bases of the industrialized world. In order to fulfill this
mission of standardization, the BIPM has to establish the basic
standards, as well as the scales of the physical quantities, and keep the
international prototypes. To this day, only the unit of mass is kept
under the form of a “materialized measure”. The other basic quantities
of the SI are defined today from physical constants, such as the
distance traveled by light in 3.34 nanoseconds (the physical constant
is the speed of light in vacuum):
– to compare the national standards to the international standards;
– to organize international comparisons at the level of national
standards;
– to ensure the coordination of the corresponding techniques of
measurement;
– to bring into existence the determinations relative to the basic
physical constants and coordinate them.

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