When was the SI established and by whom?

Question

Once again: science paper.

Answer 1

1960

International scientists

based on the metric system, which is older

"The 11th General Conference on Weights and Measures (1960) adopted the name Système International d'Unités (International System of Units, international abbreviation SI), for the recommended practical system of units of measurement.

The 11th CGPM laid down rules for the prefixes, the derived units, and other matters. The base units are a choice of seven well-defined units which by convention are regarded as dimensionally independent: the metre, the kilogram, the second, the ampere, the kelvin, the mole, and the candela. Derived units are those formed by combining base units according to the algebraic relations linking the corresponding quantities. The names and symbols of some of the units thus formed can be replaced by special names and symbols which can themselves be used to form expressions and symbols of other derived units.

The SI is not static but evolves to match the world's increasingly demanding requirements for measurement. "


http://en.wikipedia.org/wiki/SI
http://www.bipm.org/en/si/

Answer 2

The International System of Units (abbreviated SI from the French language name Système international d'unités) is the modern form of the metric system. It is the world's most widely used system of units, both in everyday commerce and in science.

The older metric system included several groupings of units. The SI was developed in 1960 from the meter-kilogram-second (mks) system, rather than the centimeter-gram-second (cgs) system which, in turn, had many variants.

The metric system was conceived by a group of scientists (among them, Lavoisier) which had been commissioned by king Louis XVI of France to create a unified and rational system of measures. After the French Revolution, the system was adopted by the new government.[1] On August 1, 1793 the National Convention adopted the new decimal "metre" with a provisional length as well as the other decimal units with preliminary definitions and terms. On April 7, 1795 (Loi du 18 germinal, an III) the terms gramme and kilogramme replaced the former terms "gravet" (correctly "milligrave") and "grave". A month after the coup of 18 Brumaire, the metric system was definitively adopted in France by the First Consul Bonaparte, (the later Napoleon I) on December 10, 1799. During the history of the metric system a number of variations have evolved and their use spread around the world replacing many traditional measurement systems.

By the end of World War II a number of different systems of measurement were still in use throughout the world. Some of these systems were metric system variations whilst others were based on the Imperial and American systems. It was recognised that additional steps were needed to promote a worldwide measurement system. As a result the 9th General Conference on Weights and Measures (CGPM), in 1948, asked the International Committee for Weights and Measures (CIPM) to conduct an international study of the measurement needs of the scientific, technical, and educational communities.

Based on the findings of this study, the 10th CGPM in 1954 decided that an international system should be derived from six base units to provide for the measurement of temperature and optical radiation in addition to mechanical and electromagnetic quantities. The six base units recommended were the metre, kilogram, second, ampere, Kelvin degree (later renamed the kelvin), and the candela. In 1960, the 11th CGPM named the system the International System of Units, abbreviated SI. The seventh base unit, the mole, was added in 1970 by the 14th CGPM.

Answer 3

The SI was established in 1960 by the 11th General Conference on Weights and Measures (CGPM, Conférence Générale des Poids et Mesures). The CGPM is the international authority that ensures wide dissemination of the SI and modifies the SI as necessary to reflect the latest advances in science and technology.

Answer 4

The International System of Units, universally abbreviated SI (from the French Le Système International d'Unités), is the modern metric system of measurement. Long the dominant system of measurement used in science, the SI is rapidly becoming the dominant system used in international commerce.

The first edition of this National Institute of Standards and Technology Publication, NIST SP 814, was published in 1991 and replaced Letter Circular LC 1132 published in 1982 by NIST's predecessor, the National Bureau of Standards (NBS). It reprinted the Department of Commerce, NIST, Federal Register notice of December 20, 1990 entitled "Metric System of Measurement: Interpretation of the International System of Units for the United States"; the Department of Commerce, Office of the Secretary, Federal Register notice of January 2, 1991 entitle "Metric Conversion Policy for Federal agencies"; and Executive Order I2770 issued by the President of the Untied States on July 25, 1991 entitled "Metric Usage in Federal Government Programs."

As for the metric system.
''metric system of measurement'' means the International System of Units as established by the General Conference of Weights and Measures in 1960 and as interpreted or modified for the United States by the Secretary of Commerce;