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International aspects of the SI     CIPM Consultative Committees
CCEM Comité Consultatif d'Électricité et Magnétisme (CCEM), new name given in 1997 to the Comité Consultatif d'Électricité (CCE) established in 1927.
The Consultative Committee for Electricity and Magnetism is concerned with practical realizations of the Sl volt, ohm, ampere, and watt, laboratory reference standards of the volt and the ohm based upon the Josephson and quantum Hall effects, capacitance standards, ac/dc measurements, and RF and microwave standards.
CCPR Comité Consultatif de Photométrie et Radiométrie (CCPR), new name given in 1971 to the Comité Consultatif de Photométrie (CCP) established in 1933 (between 1930 and 1933 the CCE dealt with matters concerning photometry).
The Consultative Committee for Photometry and Radiometry is concerned with photometric and radiometric scales, development of absolute radiometry, and radiometry for fibre optics (with the CCEM).
CCT Comité Consultatif de Thermométrie (CCT) established in 1937.
The Consultative Committee for Thermometry is concerned with the establishment and realization of the International Temperature Scale of 1990 (ITS-90), differences between T90 and thermodynamic temperature, extension and improvement of the ITS-90, secondary reference points, international reference tables for thermocouples, and resistance thermometers.
CCL Comité Consultatif des Longueurs (CCL), new name given in 1997 to the Comité Consultatif pour la Définition du Mètre (CCDM) established in 1952.
The Consultative Committee for Length is concerned with the definition and realization of the meter, and practical length and angle measurements.
CCTF Comité Consultatif du Temps et des Fréquences (CCTF), new name given in 1997 to the Comité Consultatif pour la Definition de la Seconde (CCDS) established in 1956.
The Consultative Committee for Time and Frequency is concerned with the definition and realization of the second, and the establishment and diffusion of International Atomic Time (TAI) and Coordinated Universal Time (UTC).
CCRI Comité Consultatif des Rayonnements Ionisants (CCRI), new name given in 1997 to the Comité Consultatif pour les Étalons de Mesure des Rayonnements lonisants (CCEMRI) established in 1958.
The Consultative Committee for Ionizing Radiations is concerned with definitions of quantities and units, standards for x-ray, gamma-ray and neutron dosimetry, radioactivity measurement, and the international reference system for radionuclides (SIR).
CCU Comité Consultatif des Unités (CCU) established in 1964 (this committee replaced the Commission for the System of Units established by the CIPM in 1954).
The Consultative Committee for Units is concerned with the development of the Système International d'Unités (Sl), and the preparation of successive editions of the BIPM Sl Brochure.
CCM Comité Consultatif pour la Masse et les grandeurs apparentées (CCM) established in 1980.
The Consultative Committee for Mass and Related Quantities is concerned with comparisons of mass standards with the international prototype of the kilogram, considerations affecting the definition of the unit of mass, and also density, pressure, and force standards.
CCQM Comité Consultatif pour la Quantité de Matière (CCQM) established in 1993.
The Consultative Committee for Amount of Substance is concerned with primary methods for measuring amount of substance, related international comparisons, and the establishment of international traceability between national laboratories concerned with metrology in chemistry.
CCAUV Comité Consultatif de l'Acoustique, des Ultrasons et des Vibrations (CCAUV) established in 1998.
The Consultative Committee for Acoustics, Ultrasound and Vibration is concerned with the organization of key comparisons in acoustics (airborne and underwater), in ultrasound measurement, and in vibration measurement; it acts as the focus for this diverse community, seeking to develop common aims and increased collaboration between national metrology institutes and appropriate designated organizatjions in Member Countries of the Meter Convention.

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