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R9 Laboratory SOP 460
Percent Solids (or Moisture) Determination in Solid and Semisolid Samples
Summary
This Standard Operating Procedure (SOP) is applicable to solid, semisolid and tissue samples and is used to determine percentage of solid material. If the sample matrix is of such a nature that the losses which occur in the 104°C oven can be reasonably attributed to evaporation of water then the procedure can be utilized to determine percent moisture. The procedure is not applicable to samples with extremely volatile or flammable components or which become unstable upon heating.
A representative portion of the sample is measured into a tared aluminum tin. The sample is then oven dried at 104°C for 12-24 hours, cooled in a desiccator, and weighed. The dried weight of the sample divided by the original sample weight is used to determine percent solids. The weight loss can be used to determine moisture content in an analogous fashion.