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articles:nist_traceability [2019/05/25 12:46] – [What are SI Units?] rrandallarticles:nist_traceability [2019/11/20 07:26] – [What are "intrinsic" standards?] rrandall
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 As mentioned earlier, [[https://www.fluke.com|Fluke]] 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 for DC Volts. Even though they don't send an instrument to NIST for calibration, they [[https://www.fluke.com/en-us/learn/blog/electrical/the-volt-makes-a-stop-at-the-fluke-metrology-lab|compare their Josephson voltage system to an identical Josephson Voltage system maintained by NIST]].  As mentioned earlier, [[https://www.fluke.com|Fluke]] 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 for DC Volts. Even though they don't send an instrument to NIST for calibration, they [[https://www.fluke.com/en-us/learn/blog/electrical/the-volt-makes-a-stop-at-the-fluke-metrology-lab|compare their Josephson voltage system to an identical Josephson Voltage system maintained by NIST]]. 
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 +==== Legal Metrology ====
  
 Fluke performs this comparison because, just as the requirements for “measurement traceability” contained in ISO 9001:2015 & AS9100:2016 (Rev. D) are antiquated, so is U.S. law in this area. U.S. Law has designated that NIST holds the national standards of measurement, and NIST has defined the U.S. legal volt to be produced from its one particular Josephson voltage system, so it is the national standard. However, this is only pertinent to the area of "legal metrology" (Ref.: [[https://www.oiml.org/en/about/legal-metrology|International Organization of Legal Metrology]]). Fluke performs this comparison because, just as the requirements for “measurement traceability” contained in ISO 9001:2015 & AS9100:2016 (Rev. D) are antiquated, so is U.S. law in this area. U.S. Law has designated that NIST holds the national standards of measurement, and NIST has defined the U.S. legal volt to be produced from its one particular Josephson voltage system, so it is the national standard. However, this is only pertinent to the area of "legal metrology" (Ref.: [[https://www.oiml.org/en/about/legal-metrology|International Organization of Legal Metrology]]).
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 +U.S. Regulations often require metrological traceability "to NIST". For example:
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 ===== What are "International Standards"? ===== ===== What are "International Standards"? =====
 While ISO 9001:2015, AS9100:2016 (Rev. D) and ISO 17025:2017 all mention "International Standards", I am aware of only four (4) "international standards" (as opposed to SI //units//); three of which are listed as examples in the "Bureau International des Poids et Mesures" (BIPM) [[https://www.bipm.org/utils/common/documents/jcgm/JCGM_200_2012.pdf|JCGM 200:2012, "International vocabulary of metrology – Basic and general concepts and associated terms (VIM)"]] (3rd edition), sec. 5.2, "international measurement standard". However, there are probably others. Those that I am aware of include: \\ While ISO 9001:2015, AS9100:2016 (Rev. D) and ISO 17025:2017 all mention "International Standards", I am aware of only four (4) "international standards" (as opposed to SI //units//); three of which are listed as examples in the "Bureau International des Poids et Mesures" (BIPM) [[https://www.bipm.org/utils/common/documents/jcgm/JCGM_200_2012.pdf|JCGM 200:2012, "International vocabulary of metrology – Basic and general concepts and associated terms (VIM)"]] (3rd edition), sec. 5.2, "international measurement standard". However, there are probably others. Those that I am aware of include: \\
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 </WRAP> </WRAP>
  
-Unless required by statute or regulation (i.e., for Legal Metrology), mandating "NIST traceability" unnecessarily "limits" the sources for metrological traceability, excluding other NMIs and/or accredited commercial metrology laboratories.+Unless required by statute or regulation (i.e., for [[https://www.oiml.org/en/about/legal-metrology|Legal Metrology]]), mandating "NIST traceability" unnecessarily "limits" the sources for metrological traceability, excluding other NMIs and/or accredited commercial metrology laboratories.