Editing Metrology (section)

=={{anchor|Historical development}}History==
{{see also|History of measurement}}
The ability to measure alone is insufficient; standardisation is crucial for measurements to be meaningful.<ref name="MSC-History">{{cite web|title=History of Metrology|date=17 June 2016 |url=http://www.msc-conf.com/history-of-metrology/|publisher=Measurement Science Conference|access-date=28 February 2017|url-status=live|archive-url=https://web.archive.org/web/20170301094329/http://www.msc-conf.com/history-of-metrology/|archive-date=1 March 2017}}</ref> The first record of a permanent standard was in 2900 BC, when the [[Cubit#Ancient Egyptian royal cubit|royal Egyptian cubit]] was carved from black [[granite]].<ref name="MSC-History"/> The cubit was decreed to be the length of the Pharaoh's forearm plus the width of his hand, and replica standards were given to builders.<ref name = BGtoM/> The success of a standardised length for the building of [[Giza pyramid complex|the pyramids]] is indicated by the lengths of their bases differing by no more than 0.05 percent.<ref name="MSC-History"/>

In China weights and measures had a semi religious meaning as it was used in the various crafts by the [[Kao Gong Ji|Artificers]] and in ritual utensils and is mentioned in the [[Book of Rites|book of rites]] along with the [[steelyard balance]] and other tools.<ref>{{Cite book |last=Confucius |url=https://books.google.com/books?id=cu3qDAAAQBAJ&q=book+of+rites |title=Delphi Collected Works of Confucius - Four Books and Five Classics of Confucianism (Illustrated) |date=2016-08-29 |publisher=Delphi Classics |isbn=978-1-78656-052-0 |language=en}}</ref>

Other civilizations produced generally accepted measurement standards, with Roman and Greek architecture based on distinct systems of measurement.<ref name="MSC-History"/> The collapse of the empires and the Dark Ages that followed lost much measurement knowledge and standardisation. Although local systems of measurement were common, comparability was difficult since many local systems were incompatible.<ref name="MSC-History"/> England established the Assize of Measures to create standards for length measurements in 1196, and the 1215 [[Magna Carta]] included a section for the measurement of wine and beer.<ref name="NPL-HofL">{{cite web|title=History of Length Measurement|url=http://www.npl.co.uk/educate-explore/posters/history-of-length-measurement/|publisher=National Physical Laboratory|access-date=28 February 2017|url-status=live|archive-url=https://web.archive.org/web/20170301094410/http://www.npl.co.uk/educate-explore/posters/history-of-length-measurement/|archive-date=1 March 2017}}</ref>

Modern metrology has its roots in the [[French Revolution]]. With a political motivation to harmonise units throughout France, a length standard based on a natural source was proposed.<ref name="MSC-History"/> In March 1791, the [[metre]] was defined.<ref name="French-History">{{cite web|title=History of measurement – from metre to International System of Units (SI) |url=http://www.french-metrology.com/en/history/history-mesurement.asp |publisher=La metrologie francaise |access-date=28 February 2017 |url-status=dead |archive-url=https://web.archive.org/web/20110425025041/http://www.french-metrology.com/en/history/history-mesurement.asp |archive-date=25 April 2011 }}</ref> This led to the creation of the decimal-based [[metric system]] in 1795, establishing standards for other types of measurements. Several other countries adopted the metric system between 1795 and 1875; to ensure international conformity, the [[International Bureau of Weights and Measures]] ({{langx|fr|Bureau International des Poids et Mesures}}, or BIPM) was formed by the [[Metre Convention]].<ref name = BGtoM/><ref name="French-History"/> Although the BIPM's original mission was to create international standards for units of measurement and relate them to national standards to ensure conformity, its scope has broadened to include electrical and [[Photometry (optics)|photometric]] units and [[ionizing radiation]] measurement standards.<ref name="French-History"/> The metric system was modernised in 1960 with the creation of the [[International System of Units]] (SI) as a result of a resolution at the 11th [[General Conference on Weights and Measures]] ({{langx|fr|Conference Generale des Poids et Mesures}}, or CGPM).<ref name = R12_11/>