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Report on Bilateral Key Comparison SIM.T-K6.1 on Humidity Standards in the Dew/Frost-point Temperature Range from –25 °C TO 20 °C



Christopher W. Meyer, Ken Hill


A Regional Metrology Organization (RMO) Key Comparison of dew/frost point temperatures was carried out by the National Institute of Standards and Technology (NIST, USA) and the National Research Council (NRC, Canada) between December, 2014 and April, 2015. The results of this comparison are reported here, along with descriptions of the humidity laboratory standards for NIST and NRC and the uncertainty budget for these standards. This report also describes the protocol for the comparison and presents the data acquired. The results are analyzed, determining degree of equivalence between the dew/frost-point standards of NIST and NRC.


Key Comparison, Humidity, Dew Point, Frost Point, Degree of Equivalence.
Created October 1, 2015, Updated November 10, 2018