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articles:nist_traceability [2019/01/26 14:45] – [An "unbroken chain of calibrations" to what?] rrandallarticles:nist_traceability [2019/05/19 11:25] – [What are SI Units?] rrandall
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 a. calibrated or verified, or both, at specified intervals, or prior to use, against measurement standards __traceable to international or national measurement standards; when no such standards exist, the basis used for calibration or verification shall be retained as documented information__;//" a. calibrated or verified, or both, at specified intervals, or prior to use, against measurement standards __traceable to international or national measurement standards; when no such standards exist, the basis used for calibration or verification shall be retained as documented information__;//"
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-Unfortunately, the language in ISO 9001:2015 & AS9100:2016 (Rev. D) is extremely antiquated (by about 55 years) in stating its requirements for "measurement traceability". In contrast, ISO 17025:2017 is much more modern and technically correct in stating:\\+Unfortunately, the language in ISO 9001:2015 & AS9100:2016 (Rev. D) is extremely antiquated in stating its requirements for "measurement traceability". In contrast, ISO 17025:2017 is much more modern and technically correct in stating:\\
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 **ISO 17025:2017, “General requirements for the competence of testing and calibration laboratories”** \\ **ISO 17025:2017, “General requirements for the competence of testing and calibration laboratories”** \\
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 SI Units are also explained on the NIST web site at: https://www.nist.gov/pml/weights-and-measures/metric-si/si-units SI Units are also explained on the NIST web site at: https://www.nist.gov/pml/weights-and-measures/metric-si/si-units
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 +And, alternatively, are presented in "[[https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication330e2008.pdf|NIST Special Publication 330 -  The International System of Units (SI)]]" (which will likely be updated after May 20, 2019).
  
 Because SI units are derived from intrinsic (i.e., invariant) constants of nature, "intrinsic measurement standards" exist. This is acknowledged in ISO 17025:2017, sec. 6.5.2, which provides 3 (three) different methodologies for achieving metrological traceability. And is further clarified in ISO 17025:2017, "Annex A: Metrological traceability". \\ Because SI units are derived from intrinsic (i.e., invariant) constants of nature, "intrinsic measurement standards" exist. This is acknowledged in ISO 17025:2017, sec. 6.5.2, which provides 3 (three) different methodologies for achieving metrological traceability. And is further clarified in ISO 17025:2017, "Annex A: Metrological traceability". \\