Radon is considered as the main source of man's exposure to ionizing radiation. It is a natur... more Radon is considered as the main source of man's exposure to ionizing radiation. It is a naturally occurring radioactive gas, its concentration in air depends mainly on the presence of Uranium or Thorium in the subsoil of the earth. The present study aims to demonstrate the possibility to use Solid State Nuclear Track Detectors (SSNTD) to evaluate radon concentration, particularly emanating from phosphates, and the conversion factor; allows to estimate from the radon mass activity the value of the Uranium concentration C = 2,7 ± 0,5 (ppm)/(Bq/Kg). The choice of the CR-39 SSNTD has been dictated by its sensitivity to all energies of alpha particles involved in measuring radon and its daughters.
Within the framework of the Fraunhofer diffraction theory, we investigate the intensity character... more Within the framework of the Fraunhofer diffraction theory, we investigate the intensity characteristics in the far-field region for a diffractive conical aperture irradiated by a plane wave. This calculation is applied to diffraction by conical tracks.
The present study aims to demonstrate the possibility to use only solid state nuclear tracks dete... more The present study aims to demonstrate the possibility to use only solid state nuclear tracks detectors (SSNTDs) and an α-source for the calculation of the calibration factor of LR-115 in different samples : solid, liquid or gaseous. The calibration factor is a linear function of the removed thickness of LR-115 sensitive layer, it allows the transformation of the observed tracks density in an alpha volume activity. The method has been used for the evaluation of the content 238 U in samples of phosphate as well as the rate of 222 Rn emanating from the phosphate and coal.
In this study, indoor and outdoor activities of radon and its progeny were measured using the pas... more In this study, indoor and outdoor activities of radon and its progeny were measured using the passive dosimetry CR-39 detectors inside and outside of 60 houses of El Jadida province, Morocco. Thereafter, three radiological parameters namely the potential alpha energy concentrations (PAEC), the annual effective dose (E), and the lung cancer cases per year per million person (CPPP) were calculated. The obtained results showed that the nature of construction materials, the presence of wells inside houses and the proximity of the industrial zone of Jorf Lasfar have a significant impact on indoor radon concentrations and its decay products. In fact, the registered activities go from 52 Bq m −3 in modern houses whose age is less than 20 years to 266 Bq m −3 in old houses of more than 50 years located near the industrial zone of Jorf Lasfar. The average values of the potential alpha energy concentrations, the annual effective doses, and the lung cancer risks per year per million person measured in the different houses vary respectively from 9.1 mWL, 1.50 mSv y −1 , 27 in modern houses to 48 mWL, 7.82 mSv y −1 , 141 in old houses of more than 50 years located near the industrial zone of Jorf Lasfar, values which remain close to the admissible safety limits (53.33 mWL, 10 mSv y −1 , 230). Due to this, it would be interesting and desirable to prohibit houses near industrial areas and borehole wells inside houses with a choice of construction materials adapted to the criteria of the limitation of doses.
Radon is considered as the main source of man's exposure to ionizing radiation. It is a natur... more Radon is considered as the main source of man's exposure to ionizing radiation. It is a naturally occurring radioactive gas, its concentration in air depends mainly on the presence of Uranium or Thorium in the subsoil of the earth. The present study aims to demonstrate the possibility to use Solid State Nuclear Track Detectors (SSNTD) to evaluate radon concentration, particularly emanating from phosphates, and the conversion factor; allows to estimate from the radon mass activity the value of the Uranium concentration C = 2,7 ± 0,5 (ppm)/(Bq/Kg). The choice of the CR-39 SSNTD has been dictated by its sensitivity to all energies of alpha particles involved in measuring radon and its daughters.
Within the framework of the Fraunhofer diffraction theory, we investigate the intensity character... more Within the framework of the Fraunhofer diffraction theory, we investigate the intensity characteristics in the far-field region for a diffractive conical aperture irradiated by a plane wave. This calculation is applied to diffraction by conical tracks.
The present study aims to demonstrate the possibility to use only solid state nuclear tracks dete... more The present study aims to demonstrate the possibility to use only solid state nuclear tracks detectors (SSNTDs) and an α-source for the calculation of the calibration factor of LR-115 in different samples : solid, liquid or gaseous. The calibration factor is a linear function of the removed thickness of LR-115 sensitive layer, it allows the transformation of the observed tracks density in an alpha volume activity. The method has been used for the evaluation of the content 238 U in samples of phosphate as well as the rate of 222 Rn emanating from the phosphate and coal.
In this study, indoor and outdoor activities of radon and its progeny were measured using the pas... more In this study, indoor and outdoor activities of radon and its progeny were measured using the passive dosimetry CR-39 detectors inside and outside of 60 houses of El Jadida province, Morocco. Thereafter, three radiological parameters namely the potential alpha energy concentrations (PAEC), the annual effective dose (E), and the lung cancer cases per year per million person (CPPP) were calculated. The obtained results showed that the nature of construction materials, the presence of wells inside houses and the proximity of the industrial zone of Jorf Lasfar have a significant impact on indoor radon concentrations and its decay products. In fact, the registered activities go from 52 Bq m −3 in modern houses whose age is less than 20 years to 266 Bq m −3 in old houses of more than 50 years located near the industrial zone of Jorf Lasfar. The average values of the potential alpha energy concentrations, the annual effective doses, and the lung cancer risks per year per million person measured in the different houses vary respectively from 9.1 mWL, 1.50 mSv y −1 , 27 in modern houses to 48 mWL, 7.82 mSv y −1 , 141 in old houses of more than 50 years located near the industrial zone of Jorf Lasfar, values which remain close to the admissible safety limits (53.33 mWL, 10 mSv y −1 , 230). Due to this, it would be interesting and desirable to prohibit houses near industrial areas and borehole wells inside houses with a choice of construction materials adapted to the criteria of the limitation of doses.
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