BS ISO 20899:2018 PDF

Scope: 1 Scope This document specifies methods used to determine the concentration of plutonium and neptunium isotopes in water by inductively coupled plasma mass spectrometry (ICP-MS) ( 239 Pu, 240 Pu, 241 Pu and 237 Np). The concentrations obtained can be converted into activity concentrations of the different isotopes [ 9 ] . Due to its relatively short half-life and 238 U isobaric interference, 238 Pu can hardly be measured by this method. To quantify this isotope, other techniques can be used (ICP-MS with collision-reaction cell, ICP-MS/MS with collision-reaction cell or chemical separation). Alpha spectrometry measurement, as described in ISO 13167 [ 10 ] , is currently used [ 11 ] . This method is applicable to all types of water having a saline load less than 1 g·l −1 . A dilution of the sample is possible to obtain a solution having a saline load and activity concentrations compatible with the preparation and the measurement assembly. A filtration at 0,45 μm is needed for determination of dissolved nuclides. Acidification and chemical separation of the sample are always needed. The limit of quantification depends on the chemical separation and the performance of the measurement device. This method covers the measurement of those isotopes in water in activity concentrations between around [ 12 ][ 13 ] : — 1 mBq·l −1 to 5 Bq·l −1 for 239 Pu, 240 Pu...

BS ISO 20899:2018 history

2018 BS ISO 20899:2018 Water quality. Plutonium and neptunium. Test method using ICP-MS