RT journal article T1 A Practical Procedure to Determine Natural Radionuclides in Solid Materials from Mining A1 Barba Lobo, Alejandro A1 Gázquez González, Manuel Jesús A1 Bolívar, Juan Pedro A2 Física Aplicada K1 natural radionuclides K1 NORM K1 mining K1 gamma-ray spectrometry K1 alpha-particle spectrometry K1 secular disequilibrium AB There are many regulations related to the radiological control of NORMs (Naturally Occurring Radioactive Materials) in activities such as mining, industry, etc. Consequently, it is necessary to apply fast and accurate methods to measure the activity concentrations of long-lived natural radionuclides (e.g., U-238, Th-234,Th-232,Th-230,Th-228, Ra-228,Ra-226, Pb-210, Po-210, and K-40) in samples characterized by a wide variety of compositions and densities, such as mining samples (wastes, minerals, and scales). Thus, it is relevant to calculate the radioactive index (RI), which summarizes for all radionuclides the ratio between the activity concentration and its respective threshold activity concentration as established by regulations, in order to classify a material as a NORM. To proceed with the determinations of these radionuclides, two spectrometric techniques based on both alpha-particle and gamma-ray detections should be employed. In the case of gamma-ray spectrometry, it is necessary to correct the full-energy peak efficiency (FEPE) obtained for the calibration sample, s o due to self-attenuation and true coincidence summing (TCS) effects. The correction is especially significant at low gamma emission energies, that is, E-gamma < 150 keV, such as 46 keV (Pb-210) and 63 keV (Th-234). On the other hand, in samples which contain radionuclides that are in secular disequilibrium with others belonging to the same series (U-238 or Th-232 series), like wastes or intermediate products, it is necessary to measure some pure alphaemitters (Th-232, Th-230, Po-210) by employing alpha-particle spectrometry. A practical and general validated procedure based on both alpha and gamma spectrometric techniques and using semiconductor detectors is presented in this study. PB MDPI SN 2075-163X YR 2022 FD 2022-05 LK http://hdl.handle.net/10498/27210 UL http://hdl.handle.net/10498/27210 LA eng DS Repositorio Institucional de la Universidad de Cádiz RD 13-nov-2026