SI-Traceable Water Content Measurements in Solids, Bulks, and Powders

Methods such as Karl Fischer titration and Loss-on-Drying, commonly used for estimating moisture content in samples, have been in existence for many years, but have difficulties obtaining a direct calibration chain toward water content. In recognition of this challenge, the joint research project, METefnet, was funded by the European Metrology Research Programme in 2012. The goal of METefnet is to establish a European metrology infrastructure for water content measurement and to develop primary standards for unambiguous determination of water mass fraction in materials. Here, we describe the primary standard developed by Danish Technological Institute in METefnet. This standard establishes traceability of the water content of a sample to dewpoint temperature. The standard only measures water, and the measurement result is not affected by other components.