Indexed on: 01 Apr '03Published on: 01 Apr '03Published in: Accreditation and Quality Assurance
Measurement uncertainties in the determination of 210Pb and 210Po in Reference Material IAEA-300 (Baltic Sea Sediment) were evaluated. 210Pb and 210Po were separated from the matrix using an Sr resin column. The chemical yield of 210Pb was determined gravimetrically in PbSO4 form. Precipitation was followed by beta proportional counting after 210Bi ingrowth. 210Po was determined by alpha spectrometry after its spontaneous deposition on a Cu planchet. The major source of uncertainty was identified as the statistical counting uncertainty, which was also expected and is almost impossible to reduce without extension of the time required for an analysis. The expanded uncertainties were determined as 7.4% and 12.2% for 210Pb and 210Po, respectively.