The International Bureau of Weights and Measures (french: Bureau international des poids et mesures, BIPM) is an

intergovernmental organisation An international organization or international organisation (see spelling differences), also known as an intergovernmental organization or an international institution, is a stable set of norms and rules meant to govern the behavior of states an ...

, through which its 59 member-states act together on measurement standards in four areas:

chemistry Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions ...

ionising radiation Ionizing radiation (or ionising radiation), including nuclear radiation, consists of subatomic particles or electromagnetic waves that have sufficient energy to ionize atoms or molecules by detaching electrons from them. Some particles can travel ...

, physical

metrology Metrology is the scientific study of measurement. It establishes a common understanding of units, crucial in linking human activities. Modern metrology has its roots in the French Revolution's political motivation to standardise units in Fran ...

, and

coordinated universal time Coordinated Universal Time or UTC is the primary time standard by which the world regulates clocks and time. It is within about one second of mean solar time (such as UT1) at 0° longitude (at the IERS Reference Meridian as the currently used ...

. It is based in

Saint-Cloud Saint-Cloud () is a commune in the western suburbs of Paris, France, from the centre of Paris. Like other communes of Hauts-de-Seine such as Marnes-la-Coquette, Neuilly-sur-Seine and Vaucresson, Saint-Cloud is one of France's wealthiest tow ...

Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. S ...

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

. The organisation has been referred to as IBWM (from its name in English) in older literature.

Structure

The BIPM is supervised by the

International Committee for Weights and Measures The General Conference on Weights and Measures (GCWM; french: Conférence générale des poids et mesures, CGPM) is the supreme authority of the International Bureau of Weights and Measures (BIPM), the intergovernmental organization established i ...

(french: Comité international des poids et mesures, CIPM), a committee of eighteen members that meet normally in two sessions per year, which is in turn overseen by the

General Conference on Weights and Measures The General Conference on Weights and Measures (GCWM; french: Conférence générale des poids et mesures, CGPM) is the supreme authority of the International Bureau of Weights and Measures (BIPM), the intergovernmental organization established i ...

(french: Conférence générale des poids et mesures, CGPM) that meets in Paris usually once every four years, consisting of delegates of the governments of the Member States and observers from the Associates of the CGPM. These organs are also commonly referred to by their French initialisms.

History

The BIPM was created on 20 May 1875, following the signing of the

Metre Convention The Metre Convention (french: link=no, Convention du Mètre), also known as the Treaty of the Metre, is an international treaty that was signed in Paris on 20 May 1875 by representatives of 17 nations (Argentina, Austria-Hungary, Belgium, Brazi ...

, a

treaty A treaty is a formal, legally binding written agreement between actors in international law. It is usually made by and between sovereign states, but can include international organizations An international organization or international o ...

among 17 Member States ( there are now 59 members). It is based at the

Pavillon de Breteuil The Pavillon de Breteuil is the headquarters of the International Bureau of Weights and Measures (BIPM). The building lies in the southeastern section of the Parc de Saint-Cloud in Saint-Cloud, France, to the west of Paris. It is listed in France ...

, France, a site (originally ) granted to the Bureau by the

French Government The Government of France (French: ''Gouvernement français''), officially the Government of the French Republic (''Gouvernement de la République française'' ), exercises executive power in France. It is composed of the Prime Minister, who i ...

in 1876. Since 1969 the site has been considered international territory, and the BIPM has all the rights and privileges accorded an intergovernmental organisation. This status was further clarified by the French decree No 70-820 of 9 September 1970.

Function

The BIPM has the mandate to provide the basis for a single, coherent system of measurements throughout the world, traceable to the International System of Units (SI). This task takes many forms, from direct dissemination of units to coordination through international comparisons of national measurement standards (as in electricity and ionising radiation). Following consultation, a draft version of the BIPM Work Programme is presented at each meeting of the General Conference for consideration with the BIPM budget. The final programme of work is determined by the CIPM in accordance with the budget agreed to by the CGPM. Currently, the BIPM's main work includes: * Scientific and technical activities carried out in its four departments: chemistry, ionising radiation, physical metrology, and time * Liaison and coordination work, including providing the secretariat for the CIPM Consultative Committees and some of their Working Groups and for the CIPM MRA, and providing institutional liaison with the other bodies supporting the international quality infrastructure and other international bodies * Capacity building and knowledge transfer programs to increase the effectiveness within the worldwide metrology community of those Member State and Associates with emerging metrology systems * A resource centre providing a database and publications for international metrology The BIPM is one of the twelve member organisations of the International Network on Quality Infrastructure (INetQI), which promotes and implements QI activities in

, accreditation, standardisation and conformity assessment. The BIPM has an important role in maintaining accurate worldwide time of day. It combines, analyses, and averages the official atomic time standards of member nations around the world to create a single, official

Coordinated Universal Time Coordinated Universal Time or UTC is the primary time standard by which the world regulates clocks and time. It is within about one second of mean solar time (such as UT1) at 0° longitude (at the IERS Reference Meridian as the currently used ...

(UTC).

Directors

Since its establishment, the directors of the BIPM have been:

References

External links