Short answer: According to the proceedings from the 96th meeting of the CIPM (2007), CMC uncertainty is a calibration and measurement capability available to customers under normal conditions: As published in the BIPM key comparison database (KCDB) of the CIPM MRA or as described in the laboratory’s scope of accreditation granted by an ILAC-MRA signatory. […]
Short answer: Calibration uncertainty is calculated by combining the CMC uncertainty, UUT resolution, and UUT repeatability using the square root of the sum of squares (RSS) method per the JCGM 100:2008 section 5.1.2 and ILAC P14 section 5.3. The combined uncertainty is expanded to a 95.45 % confidence interval using an appropriate coverage factor (k), […]
Short answer: Calibration uncertainty is the measurement uncertainty expressed in calibration reports at a 95 % confidence interval, where k=2, with two significant digits. It is calculated by combining the laboratory’s CMC uncertainty with the Unit Under Test (UUT) resolution and repeatability per ILAC P14. Calibration Uncertainty Reporting Requirements Per ILAC P14 Section […]
Short answer: Divide the absolute uncertainty by the absolute value of the result. To express relative uncertainty as a percentage, multiply by 100. To express relative uncertainty as a part per million, multiply by 1,000,000. Step-by-Step Instructions: Relative Uncertainty as a Percentage Calculate the absolute expanded uncertainty. Divide the absolute uncertainty by the absolute […]
Short answer: Relative uncertainty is measurement uncertainty divided by the absolute value of the measurement or result so it can expressed in a term relative to the measurand, such as a percentage, parts-per-million, etc. According to the Vocabulary in Metrology (VIM), relative standard measurement Uncertainty is the “standard measurement uncertainty divided by the absolute value […]
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