<Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (January 2017) (Learn how and when to remove this template message) </Td> </Tr> <P> Metrication (or metrification) is the process of introducing the International System of Units, also known as SI units or the metric system, to replace a jurisdiction's traditional measuring units . Although all U.S. customary units have been redefined in terms of SI units, as of 2017 the United States is one of only seven countries, including Myanmar (Burma), Liberia, Palau, the Marshall Islands, the Federated States of Micronesia, and Samoa . that have not officially adopted the metric system as the primary means of weights and measures . However, both Myanmar and Liberia are reportedly essentially metric, even without official legislation . </P> <P> Although customary units are used more often than metric units in the U.S., the SI system is used extensively in some fields such as science, medicine, the military, automobile production and repair, and international affairs . Post 1994 federal law also mandates most packaged consumer goods be labeled in both customary and metric units . Still, most Americans are unable to make metric conversions, but smartphone apps can help (e.g. on iOS and Android). </P> <P> Although the Constitution grants Congress the authority to determine standards of measure, it was not until 1832 that the customary system of units was formalized . In the early 19th century, the U.S. Coast and Geodetic Survey, the government's surveying and map - making agency, used meter standard ("Commitee Meter", French: Mètre des Archives) brought from Switzerland . Shortly after the American Civil War, the 39th United States Congress protected the use of the metric system in commerce with the Metric Act of 1866 and supplied each state with a set of standard metric weights and measures . In 1875 the United States solidified its commitment to the development of the internationally recognized metric system by becoming one of the original seventeen signatory nations to the Metre Convention, also known as the Treaty of the Metre . The signing of this international agreement concluded five years of meetings in which the metric system was reformulated, refining the accuracy of its standards . The Metre Convention established the International Bureau of Weights and Measures (Bureau international des poids et mesures, BIPM) in Sèvres, France, to provide standards of measurement for worldwide use . </P>

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