Calculation of the Expanded Uncertainty of the Measurements of the Moisture Content of a Lot of Paper Samples

Oven drying at 105°C is considered as a method for the laboratory determination of the dry matter content. It is in this work applicable for papers and boards which do not contain other chemical substances, other than water, in order to determine its moisture content. This work is aimed to further apply the ISO approach into the laboratory using four paper substrates and to statistically analyse the results of the experiments. Importance is given as to the appropriate sampling procedure, as well as the conditioning of the quality control sample paper. The determinations of the moisture content are carried out in an oven at 105°C, for 16 hours. The analytical results show a moisture content of 4%-6%w/w for the paper substrates examined. The moisture content is finally expressed as a percentage mass fraction.