A determination of the concentration level of lead Pb-210 isotope in solid samples for the assessment of radiation risk occurring in coal mines

Lead Pb-210, an element of the natural uranium radioactive decay series, is not currently considered a source of radiation risk, especially in a radiation protection system in underground mines in Poland. However, it could be a completely independent element of the radioactive series due to its physical and chemical properties. Routine measurements showed significantly higher than expected concentrations of Pb-210 in underground radium rich sediments, based only on the radioactive decay law. This phenomenon implies a need of Pb-210 concentration monitoring in such sediments. Nevertheless, the laboratory analysis of Pb-210 by gamma radiation spectroscopy is connected with a particular hindrance, the self-attenuation of Pb-210 radiation in samples. Current work describes a practical method for obtaining the self-attenuation correction factor in the case of Pb-210 concentration analysis. Experimentally obtained correction factors range between 0.51–6.96 cm²/g. Neglecting this factor can cause a significant error or underestimations in radiological risk assessment.