ISO 13163:2013 pdf download.Water quality一Lead-210一Test method using liquid scintillation counting.
ISO 13163 specifies the determination of lead-210 activity concentration in samples of all types of water using liquid scintillation counting (LSC). For raw and drinking water, the sample should be degassed in order to minimize the ingrowth of 2lOPb from radon-222.
Higher 210Pb activity concentrations can be measured by either diluting the sample or using smaller sample aliquots or both.
It is the laboratory’s responsibility to ensure the suitability of this test method for the water samples tested.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC Guide 98-3, Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in measurement (GUM:1995)
ISO/IEC Guide 99, International vocabulary of metrology — Basic and general concepts and associated terms (VIM)
ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories ISO 5667-3, Water quality — Sampling — Part 3: Preservation and handling of water samples
ISO 11929, Determination of the characteristic limits (decision threshold, detection limit and limits of the confidence interval) for measurements of ionizing radiation — Fundamentals and application
ISO 80000-10, Quantities and units — Part 10: Atomic and nuclear physics
4 Principle
21OPb is a natural beta-emitting radionuclide with a maximum beta-energy of 63,9 keV and a half-life of 22,23 years (References [15][l6]). It appears in the 238U decay series (4n+2) as a long-lived decay product of 222Rn (see Figure 1).
2lOPb is separated from its daughters, bismuth-210 and polonium-210, by extraction chromatography and its activity is measured by liquid scintillation counting, either directly after its separation or indirectly after ingrowth of its progeny bismuth-210. Other separation methods exist (Reference [17]).
To avoid the possible interferences of the isotopes lead-211 and lead-214 and their progenies during the liquid scintillation counting, it is recommended to wait at least 3 h between elution of lead and the sample counting to allow these radionuclides to fully decay.
For radloisotopes with longer half-lives such as lead-212 and its progenies, their interferences are avoided by choosing appropriate counting windows as their energies are much higher than the energy of 2lOpb (see 7.42).
For samples with high activity concentration, dilution of the sample is required to avoid resin and detector saturation during the separation and counting steps, respectively.
Suspended material is removed prior to analysis by filtration using 0,45 um filters. The analysis of the in soluble fraction requires a mineralization step that is not covered by ISO 13163.ISO 13163 pdf download.