Determination of 210Pb by direct gamma-ray spectrometry, beta counting via 210Bi and alpha-particle spectrometry via 210Po in coal, slag and ash samples from thermal power plant

In order to compare three different techniques and estimate radiological impact, activity concentration of Pb-210 in coal, slag and ash samples from thermal power plant "Nikola Tesla", Serbia, were measured, and results are presented in this study. Determination of Pb-210 was carried out in three ways: using HPGe gamma spectrometer and via in-growth of Po-210 and Bi-210 by alpha-particle spectrometry and proportional counting, respectively. The results obtained for three different techniques were compared. Statistical analysis and comparison of methods were carried out by combination of Z score and chi (2) statistical tests. Tests results, as well as values of measured activities concentrations obtained by alpha and gamma spectrometry, showed that gamma spectrometry is a valid alternative to time-consuming alpha spectrometry for low level activity measurements of Pb-210. This remark is also valid even for gamma spectrometers with poor efficiency in low energy region.