ISO 11465:2025
Sludge and solid environmental matrices - Determination of dry residue or water content and calculation of the dry matter fraction on a mass basis
This document specifies methods for the calculation of the dry matter fraction of sludge, sludge products, treated biowaste, soil and waste for which the results of performed analysis are calculated to the dry matter basis. Depending on the nature and origin of the sample, the calculation is based on a determination of the dry residue (method A) or a determination of the water content (methods A and B). It applies to samples containing more than 1 % (mass fraction) of dry residue or more than 1 % (mass fraction) of water.Method A applies to sludge, sludge products, treated biowaste, soil and solid waste. Method B applies to liquid waste and to samples which are suspected or known to contain volatiles except for water.
This document specifies methods for the calculation of the dry matter fraction of sludge, sludge products, treated biowaste, soil and waste for which the results of performed analysis are calculated to the dry matter basis. Depending on the nature and origin of the sample, the calculation is based on a determination of the dry residue (method A) or a determination of the water content (methods A and B). It applies to samples containing more than 1 % (mass fraction) of dry residue or more than 1 % (mass fraction) of water.
Method A applies to sludge, sludge products, treated biowaste, soil and solid waste. Method B applies to liquid waste and to samples which are suspected or known to contain volatiles except for water.
The method specified can be applied to all types of soil samples. Different procedures are specified for air-dried soil samples, e.g. samples pretreated according to ISO 11464, and for field-moist soil samples. Its principle is drying soil samples to constant mass at 105 °C and using the difference in mass of an amount of soil before and after the drying procedure to calculate the dry matter and water contents on a mass basis. For the determination of soil water content on a volume basis, refer to ISO 11461.
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