ISO/CD 20041-3:2026

ISO 20041-3 describes analysis methods for the determination of tritium and carbon-14 activities by liquid scintillation counting and calculation methods to determine the tritium activities discharged as tritiated water vapour (HTO) and tritium in other chemical compounds (non-HTO) as wells as carbon-14 activities discharged as carbon dioxide (14CO2) and carbon-14 in other chemical compounds (non-14CO2). The results of the measurement are therefore expressed in becquerels. ISO 20041-3 applies to samples that were obtained on molecular sieves according to ISO 20041-1 and that are representative of a certain volume stream or volume of discharge during a given period of time and of the corresponding volume discharged. This document does not apply to tritium and carbon-14 activity concentrations in the environmental air, e. g. in the vicinity of nuclear installations.