ISO 17505:2025

Soil and waste characterization — Temperature dependent differentiation of total carbon (TOC400, ROC, TIC900) ISO 17505:2025

Publication date:   Jun 4, 2025

Scope

This document specifies a method for the differentiated determination of the organic carbon content (TOC400) which is released at temperatures up to 400 °C, the residual oxidizable carbon (ROC) (including e.g. lignite (brown coal), hard coal, charcoal, black carbon, soot) and the inorganic carbon (TIC900) which is released at temperatures up to 900 °C.
The basis of this method is the dry combustion or decomposition of carbon to CO2 in the presence of oxygen or non-oxygen conditions using temperatures ranging from 150 °C to 900 °C in dry solid samples of sediment, soil, soil with anthropogenic admixtures and solid waste (see Table 1) with carbon contents of more than 1 g per kg (0,1 % C) (per carbon type in the test portion).
NOTE            TIC900’ includes the TIC measured after acid addition e.g. by ISO 10694 or EN 15936. TOC400 is a fraction of TOC measured according to e.g. ISO 10694 or EN 15936.