DIN EN ISO 13162:2015-11

This International Standard specifies the conditions for the determination of 14C activity concentration in samples of environmental water or of 14C-containing water using liquid scintillation counting. The method is applicable to the analysis of any organic molecule soluble in water that is well mixed with the scintillation cocktail. It does not apply to micelles or "large" particles (lipids, fulvic acid, humic acid, etcetera) that are inadequately mixed with the scintillation cocktail and the water. Some beta energy is lost without any excitation of the scintillation cocktail and the results are underestimated. The method is not applicable to the analysis of organically bound 14C, whose determination requires additional chemical processing (such as chemical oxidation, combustion). It is possible to determine 14C activity concentrations below 10(up)6 Bq/l without any sample dilution. The text of ISO 13162:2011 has been prepared by Technical Committee ISO/TC 147 "Water quality" of the International Organization for Standardization (ISO) and adopted as FprEN ISO 13162:2015 by Technical Committee CEN/TC 230 "Water Analysis", the secretariat of which is held by DIN (Germany). The responsible German committee is Working Committee NA 119-01-03 AA "Wasseruntersuchung" ("Water examination") at DIN Standards Committee Water Practice (NAW).