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articles:nist_traceability [2019/11/20 07:48] – [An "unbroken chain of calibrations" to what?] rrandallarticles:nist_traceability [2020/01/15 15:06] – [An "unbroken chain of calibrations" to what?] rrandall
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 [[http://www.isobudgets.com/measurement-traceability-complying-iso-17025-requirements/|{{ :articles:measurement-traceability-pyramid-600px.jpg?direct }}]] [[http://www.isobudgets.com/measurement-traceability-complying-iso-17025-requirements/|{{ :articles:measurement-traceability-pyramid-600px.jpg?direct }}]]
  
-I describe the above pyramid as "//typical//" because, contrary to the antiquated language of ISO 9001:2015 & AS9100:2016, it is possible to “bypass” the National Metrology Institutes (NMIs) to obtain traceability to SI units. Using the example of DC volts, [[https://www.fluke.com|Fluke]], a world leader in the field of metrology, owns a [[https://nvlpubs.nist.gov/nistpubs/jres/095/jresv95n3p219_A1b.pdf|Josephson voltage system]], which they can use to realize the SI Units directly.+I describe the above pyramid as "//typical//" because, contrary to the antiquated language of ISO 9001:2015 & AS9100:2016, it is possible to “bypass” the National Metrology Institutes (NMIs) to obtain traceability directly to SI units. Using the example of DC volts, [[https://www.fluke.com|Fluke]], a world leader in the field of metrology, owns a [[https://nvlpubs.nist.gov/nistpubs/jres/095/jresv95n3p219_A1b.pdf|Josephson voltage system]], which they can use to realize the SI Units directly
 + 
 +Also, while not strictly speaking an NMI, the BIPM offers [[https://www.bipm.org/en/bipm-services/|calibration & Measurement services]] (with traceability to SI Units) to Member States
 ===== What are SI Units? ===== ===== What are SI Units? =====
 {{ :articles:2018-si.png?direct&130|}} {{ :articles:2018-si.png?direct&130|}}