Simultaneous Measurement of Radon and Thoron Exhalation Rate from Soil and Building Materials
Simultaneous measurement of radon and thoron exhalation rate from soil and building materials
C. Cosma, O. Cozar , T. Jurcut, C. Baciu , I. Pop
Babes-Bolyai University, Physics Department, 3400-Cluj-Napoca, Romania
University of Oradea, Sciences Department, 3700, Oradea, Romania
Babes-Bolyai University, Geology Department, 3400-Cluj-Napoca, Romania
Technical University, Physics Department, 3400, Cluj-Napoca, Romania
Our paper presents two methods for simultaneous measurement of radon and thoron exhalation from soil and building materials: (1)-charcoal adsorption, respectively (2)-Lucas cell method.
The both methods are applicable especially in the case of a soil flux enhanced in thoron gas. In the Lucas cell case a short accumulation time was used (10-15 minutes). The thoron concentration under accumulation volume was measured immediately after the sample gas extraction and a regression equation is used for determining equilibrium thoron concentration. In the case of charcoal method the thoron was measured 4 hours after a special degassing of the sample. Using the LUK-3A device for the building materials, the thoron flux was measured only on a special enhanced thorium+radium sample
1. INTRODUCTION
The radon isotopes 220Rn (thoron) and 222Rn (radon) were intensely studied in the last time due to their involvement in the lung cancer risk [1] and also for geological purposes [2]. The main sources of the indoor radon are the soil radon and radon exhalation from building materials [3]. The active charcoal was often utilized for radon measurement especially for indoor radon [4-5]. The method of the soil radon and exhalation measurement from the soil and building materials using adsorption in active charcoal was also used [6-8] with good results but in this case corrections regarding charcoal humidity related of the break point of charcoal are needed [9]. In all these cases the radon adsorbed in charcoal is measured by gamma spectrometry,
C. Cosma, O. Cozar , T. Jurcut, C. Baciu , I. Pop
Babes-Bolyai University, Physics Department, 3400-Cluj-Napoca, Romania
University of Oradea, Sciences Department, 3700, Oradea, Romania
Babes-Bolyai University, Geology Department, 3400-Cluj-Napoca, Romania
Technical University, Physics Department, 3400, Cluj-Napoca, Romania
Our paper presents two methods for simultaneous measurement of radon and thoron exhalation from soil and building materials: (1)-charcoal adsorption, respectively (2)-Lucas cell method.
The both methods are applicable especially in the case of a soil flux enhanced in thoron gas. In the Lucas cell case a short accumulation time was used (10-15 minutes). The thoron concentration under accumulation volume was measured immediately after the sample gas extraction and a regression equation is used for determining equilibrium thoron concentration. In the case of charcoal method the thoron was measured 4 hours after a special degassing of the sample. Using the LUK-3A device for the building materials, the thoron flux was measured only on a special enhanced thorium+radium sample
1. INTRODUCTION
The radon isotopes 220Rn (thoron) and 222Rn (radon) were intensely studied in the last time due to their involvement in the lung cancer risk [1] and also for geological purposes [2]. The main sources of the indoor radon are the soil radon and radon exhalation from building materials [3]. The active charcoal was often utilized for radon measurement especially for indoor radon [4-5]. The method of the soil radon and exhalation measurement from the soil and building materials using adsorption in active charcoal was also used [6-8] with good results but in this case corrections regarding charcoal humidity related of the break point of charcoal are needed [9]. In all these cases the radon adsorbed in charcoal is measured by gamma spectrometry,
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