ISO 23649:2025 | IULTCS/IUC 444

This document specifies a method for determining the total content of the following cyclosiloxanes in chemicals for the leather tanning industry: —     octamethylcyclotetrasiloxane (D4); —     decamethylcyclopentasiloxane (D5); —     dodecamethylcyclohexasiloxane (D6); This method requires the use of gas chromatography (GC) equipped with a single quadrupole mass spectrometer (MS) to identify and quantify the cyclosiloxanes.