In this paper we present the results of a survey of indoor radon concentration levels in Mexico. In order to investigate whether differences in climate translate into significant differences in indoor radon concentrat...In this paper we present the results of a survey of indoor radon concentration levels in Mexico. In order to investigate whether differences in climate translate into significant differences in indoor radon concentrations, the country was divided into three climate regions: the northern semi-desert region, the central semitropical region and the southern tropical region. The survey was carried out using nuclear track methodology. The dosimeters employed for the survey were based on the passive closed-end cup device, developed at the Physics Institute of the National Autonomous University of Mexico, and used PADC as detector material. A well-established protocol for chemically etching and reading the detectors was followed. Average annual temperatures differ between regions (from 15℃ to 28℃) but vary relatively little within each region. Atmospheric temperature is one of the most important factors which need to be considered when carrying out a survey of indoor radon concentrations because temperature largely determines building ventilation habits, and ventilation habits are known to have significant effects on indoor radon concentrations. Other factors, including building construction materials, architectural styles, geological and hydrological characteristics, and seismicity, vary from region to region and within each region. In each of the three regions low levels of indoor radon (from 37 to 179 Bq·m-3) were found.展开更多
This work presents the results of the Radon (220Rn and 222Rn) measurements made with 486 chips of CR-39 (Allyl Dyglicol Poly Carbonate) MASL? bared detectors, in a reticular mode distribution, inside of a cellar with ...This work presents the results of the Radon (220Rn and 222Rn) measurements made with 486 chips of CR-39 (Allyl Dyglicol Poly Carbonate) MASL? bared detectors, in a reticular mode distribution, inside of a cellar with average indoor radon concentration 862 ± 49 Bq/m3. The exposure time was 3 months, in microclimate condition of constant temperature, humidity, barometric pressure and no airflow. After these 3 months, all the detectors were chemically etched in KOH 6.25 M solution at 60°C ± 1°C for 18 hours, following a very well established protocol for indoor radon survey by the Dosimetry Applications Laboratory of the Physics Institute of the National Autonomous University of Mexico, and later read automatically by CADIS (Counting Automatically Digital Image System). The results show that each one of the nine measured planes is not homogeneous presenting important differences of indoor radon concentration values. Specifically, the Radon (220Rn and 222Rn) concentration levels vary for each measured point within the cellar. It is a very important observation to consider for the calculation of dose and radiological risk.展开更多
文摘In this paper we present the results of a survey of indoor radon concentration levels in Mexico. In order to investigate whether differences in climate translate into significant differences in indoor radon concentrations, the country was divided into three climate regions: the northern semi-desert region, the central semitropical region and the southern tropical region. The survey was carried out using nuclear track methodology. The dosimeters employed for the survey were based on the passive closed-end cup device, developed at the Physics Institute of the National Autonomous University of Mexico, and used PADC as detector material. A well-established protocol for chemically etching and reading the detectors was followed. Average annual temperatures differ between regions (from 15℃ to 28℃) but vary relatively little within each region. Atmospheric temperature is one of the most important factors which need to be considered when carrying out a survey of indoor radon concentrations because temperature largely determines building ventilation habits, and ventilation habits are known to have significant effects on indoor radon concentrations. Other factors, including building construction materials, architectural styles, geological and hydrological characteristics, and seismicity, vary from region to region and within each region. In each of the three regions low levels of indoor radon (from 37 to 179 Bq·m-3) were found.
文摘This work presents the results of the Radon (220Rn and 222Rn) measurements made with 486 chips of CR-39 (Allyl Dyglicol Poly Carbonate) MASL? bared detectors, in a reticular mode distribution, inside of a cellar with average indoor radon concentration 862 ± 49 Bq/m3. The exposure time was 3 months, in microclimate condition of constant temperature, humidity, barometric pressure and no airflow. After these 3 months, all the detectors were chemically etched in KOH 6.25 M solution at 60°C ± 1°C for 18 hours, following a very well established protocol for indoor radon survey by the Dosimetry Applications Laboratory of the Physics Institute of the National Autonomous University of Mexico, and later read automatically by CADIS (Counting Automatically Digital Image System). The results show that each one of the nine measured planes is not homogeneous presenting important differences of indoor radon concentration values. Specifically, the Radon (220Rn and 222Rn) concentration levels vary for each measured point within the cellar. It is a very important observation to consider for the calculation of dose and radiological risk.
