scholarly journals Non-Uniformity of the Indoor Radon Concentration under a Convective Mixing Mechanism

2018 ◽  
Vol 15 (12) ◽  
pp. 2826
Author(s):  
Sergey Spotar ◽  
Nurlan Ibrayev ◽  
Aigerim Uyzbayeva ◽  
Jamil Atabayev
Keyword(s):  
Radon Concentration ◽  
Indoor Radon ◽  
Radioactive Decay ◽  
Cfd Modeling ◽  
Indoor Radon Concentration ◽  
Convective Mixing ◽  
Computational Fluid Dynamics Cfd ◽  
Air Tightness ◽  
Transport Problems ◽  
The Impact

This paper focuses on the results of computational fluid dynamics (CFD) modeling of radon concentration distribution in living areas within residences. The COMSOL Multiphysics® 5.3 software package has been employed for solving coupled momentum and species transport problems together with pseudo-reaction term modeling of the radon radioactive decay process. The reliability and verification of the simulation model was tested by comparing with available experimental data. The obtained results show the existence of stagnant zones where the concentration of radon is substantially higher than the average values. The impact of factors such as wind velocity, air tightness, and incoming radon flux were taken into consideration.

scholarly journals A new approach to radon temporal correction factor based on active environmental monitoring devices

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
T. Dicu ◽  
B. D. Burghele ◽  
M. Botoş ◽  
A. Cucoș ◽  
G. Dobrei ◽  
...  
Keyword(s):  
Radon Concentration ◽  
Residential Buildings ◽  
Indoor Radon ◽  
Smart Device ◽  
Correction Factors ◽  
Indoor Radon Concentration ◽  
Radon Measurements ◽  
The Impact ◽  
Monitoring Devices ◽  
Temporal Correction

AbstractThe present study aims to identify novel means of increasing the accuracy of the estimated annual indoor radon concentration based on the application of temporal correction factors to short-term radon measurements. The necessity of accurate and more reliable temporal correction factors is in high demand, in the present age of speed. In this sense, radon measurements were continuously carried out, using a newly developed smart device accompanied by CR-39 detectors, for one full year, in 71 residential buildings located in 5 Romanian cities. The coefficient of variation for the temporal correction factors calculated for combinations between the start month and the duration of the measurement presented a low value (less than 10%) for measurements longer than 7 months, while a variability close to 20% can be reached by measurements of up to 4 months. Results obtained by generalized estimating equations indicate that average temporal correction factors are positively associated with CO2 ratio, as well as the interaction between this parameter and the month in which the measurement took place. The impact of the indoor-outdoor temperature differences was statistically insignificant. The obtained results could represent a reference point in the elaboration of new strategies for calculating the temporal correction factors and, consequently, the reduction of the uncertainties related to the estimation of the annual indoor radon concentration.

scholarly journals Assessing the Impact of Housing Features and Environmental Factors on Home Indoor Radon Concentration Levels on the Navajo Nation

2020 ◽  
Vol 17 (8) ◽  
pp. 2813
Author(s):  
Sheldwin A. Yazzie ◽  
Scott Davis ◽  
Noah Seixas ◽  
Michael G. Yost
Keyword(s):  
Radon Concentration ◽  
Indoor Radon ◽  
Decay Product ◽  
Indoor Radon Concentration ◽  
Navajo Nation ◽  
Home Ventilation ◽  
Radon Gas ◽  
The Mean ◽  
The Impact ◽  
Concentration Levels

Uranium is naturally found in the environment as a radioactive metal element with high concentrations in the Southwestern US. In this region is the Navajo Nation, which spans approximately 69,930 square kilometers. A decay product of uranium is radon gas, a lung carcinogen that has no color, odor, or taste. Radon gas may pass from soil into homes; and, indoor accumulation has been associated with geographical location, seasonality, home construction materials, and home ventilation. A home and indoor radon survey was conducted from November 2014 through May 2015, with volunteers who reported residence on the Navajo Nation. Home geolocation, structural characteristics, temperature (°C) during radon testing, and elevation (meters) were recorded. Short-term indoor radon kits were used to measure indoor radon levels. 51 homes were measured for indoor radon levels, with an arithmetic mean concentration of 60.5 Becquerels per cubic meter (Bq/m3) (SD = 42.7). The mean indoor radon concentrations (Bq/m3) by house type were: mobile, 29.0 (SD = 22.9); wood, 58.6 (SD = 36.0); hogan, 74.0 (SD = 0.0); homes constructed of cement and wood, 82.6 (SD = 3.5); and homes constructed of concrete and cement, 105.7 (SD = 55.8). A key observation is that house construction type appears to be associated with the mean home indoor radon concentration. This observation has been published in that the basic structural make-up of the home may affect home ventilation and therefore indoor radon concentration levels.

scholarly journals A simple model for the assessment of indoor radionuclide Pb-210 surface contamination due to the presence of radon

2013 ◽  
Vol 28 (1) ◽  
pp. 68-72
Author(s):  
Dusan Mrdja ◽  
Istvan Bikit ◽  
Miroslav Veskovic ◽  
Sofija Forkapic ◽  
Natasa Todorovic ◽  
...  
Keyword(s):  
Radon Concentration ◽  
Indoor Radon ◽  
Radioactive Decay ◽  
Surface Contamination ◽  
Historical Period ◽  
Indoor Radon Concentration ◽  
Average Value ◽  
Retrospective Assessment ◽  
Concentration Changes

The presented, very simplified model provides a possibility for estimation of surface Pb-210 activity, depending on the changes of Rn-222 concentration during the long-term radon presence inside the closed room. This can be useful for retrospective assessment of the average indoor radon concentration for certain historical period, based on the surface contamination by the radionuclide Pb-210 in a closed or poorly ventilated room over a long period of time. However, the surface Pb-210 contamination depends on the pattern of radon concentration changes, and in this model is supposed that the change of indoor radon concentration, which periodically enters the room, is affected only by the radioactive decay and the inserted amount of radon in each entry. So, each radon entry can be comprehended as a ?net amount? of radon, or excess which remains inside the room due to radon?s periodical in-out flow. It is shown, that under the conditions of the model, the achieved average value of radon concentration of 275 Bq/m3, implies that the saturated surface contamination by the Pb-210 of 160 Bq/m2 after approximately 150 years.

scholarly journals Radon and thoron exhalation rate measurements from building materials used in Serbia

Nukleonika ◽  
2020 ◽  
Vol 65 (2) ◽  
pp. 111-114
Author(s):  
Igor T. Čeliković ◽  
Gordana K. Pantelić ◽  
Miloš Z. Živanović ◽  
Ivana S. Vukanac ◽  
Jelena D. Krneta Nikolić ◽  
...  
Keyword(s):  
Building Material ◽  
Radon Concentration ◽  
Building Materials ◽  
Indoor Radon ◽  
Exhalation Rate ◽  
Indoor Radon Concentration ◽  
Active Device ◽  
Closed Chamber ◽  
Materials Used ◽  
The Impact

AbstractThe second most important source of indoor radon, after soil beneath dwelling, is building material. With the increase in environmental awareness and new energy-saving policies, residents tend to replace the existing windows with tighter windows, which leads to a decrease in air exchange rate and consequently an increase in indoor radon concentration. In case of low exchange rates, dose caused by inhalation of radon and its progeny can exceed external dose originating from the radium content in the surrounding building material. In this paper, surface exhalation rates of radon (222Rn) and thoron (220Rn) from typical building materials used for construction and interior decoration of houses in Serbia were investigated. Surface exhalation rate measurements were performed using the closed-chamber method, while concentrations of radon and thoron in the chamber were continuously measured using an active device, RTM1688-2, produced by SARAD® GmbH. Finally, the impact of the replacement of windows on the indoor radon concentration was estimated.

Distribution characteristics on indoor radon concentration of multiple-use facilities in Gwangju area

2019 ◽  
Vol 18 (2) ◽  
pp. 177-184 ◽  
Author(s):  
Min-jin Kim ◽  
Sang-su An ◽  
Min-cheol Cho ◽  
Se-il Park ◽  
Jong-min Kim ◽  
...  
Keyword(s):  
Radon Concentration ◽  
Indoor Radon ◽  
Distribution Characteristics ◽  
Multiple Use ◽  
Indoor Radon Concentration

Indoor radon concentration in the rural dwellings of Chhattisgarh state (India)

2006 ◽  
Vol 119 (1-4) ◽  
pp. 434-437 ◽  
Author(s):  
M. S. K. Khokhar ◽  
R. S. Kher ◽  
V. B. Rathore ◽  
T. V. Ramachandran
Keyword(s):  
Radon Concentration ◽  
Indoor Radon ◽  
Indoor Radon Concentration

scholarly journals Seasonal indoor radon studies in buildings of Accra Metropolis of Greater Accra region of Ghana

2018 ◽  
Vol 53 (3) ◽  
pp. 199-206 ◽  
Author(s):  
F. Otoo ◽  
E.O. Darko ◽  
M. Garavaglia ◽  
C. Giovani ◽  
S. Pividore ◽  
...  
Keyword(s):  
Radon Concentration ◽  
Rainy Season ◽  
Indoor Radon ◽  
Dry Season ◽  
Strong Positive Correlation ◽  
Cumulative Frequency Distribution ◽  
Indoor Radon Concentration ◽  
Kolmogorov Smirnov ◽  
Greater Accra Region ◽  
Action Levels

Indoor radon concentration for annual, rainy and dry season have been studied in 228 buildings which includes bedroom, kitchen, sitting room, laboratories and offices in Accra metropolis of Greater Accra of Ghana. The passive radon CR-39 SSNTD was used for this study. The cumulative frequency distribution, normalizing Q-Q plots, Kolmogorov-Smirnov and Shapiro-Wilk statistical test showed that the result of both workplaces and dwellings are not normally distributed. The strong positive correlation between the two seasons occurred at 95% confidence level with 2 tailed. The rainy season recorded highest coefficient variation of r2 = 0.982. Statistical analysis of median (39.3), AM (103.4), GM (57.9) and GSD (3.2) for rainy season were greater than that of the dry season of median (26.9), AM (88.2), GM (49.2) and GSD (2.8) respectively. Rainy season was found to contain high radon concentrations than the dry season for all the studied locations. In general, workplace had radon concentration far greater than dwellings. The results obtained from this study ranged between 13.6 to 533.7 Bq/m3, out of which 9.6%, 12.7% and 3.5% were found to be greater than action levels proposed by WHO, EC and ICRP.

scholarly journals Long-Term Impacts of Weather Conditions on Indoor Radon Concentration Measurements in Switzerland

Atmosphere ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 92
Author(s):  
Joan Frédéric Rey ◽  
Stéphane Goyette ◽  
Mauro Gandolla ◽  
Martha Palacios ◽  
Fabio Barazza ◽  
...  
Keyword(s):  
Radon Concentration ◽  
Indoor Radon ◽  
Weather Conditions ◽  
Indoor Environments ◽  
Indoor Radon Concentration ◽  
Prone Area ◽  
Building Characteristics ◽  
Study Sites ◽  
Radon Measurements

Radon is a natural and radioactive gas that can accumulate in indoor environments. Indoor radon concentration (IRC) is influenced, among other factors, by meteorology, which is the subject of this paper. Weather parameters impact indoor radon levels and have already been investigated, but rarely in Switzerland. Moreover, there is a strong need for a better understanding of the radon behaviour inside buildings in Switzerland for public health concerns as Switzerland is a radon prone area. Based on long-term, continuous, and hourly radon measurements, radon distributions classified according to different weather event definitions were investigated and then compared at three different study sites in Western Switzerland. Outdoor temperature influences the most indoor radon, and it is globally anti-correlated. Wind influences indoor radon, but it strongly depends on intensity, direction, and building characteristics. Precipitation influences periodically indoor radon levels relatively to their intensity. Atmospheric pressure and relative humidity do not seem to be huge determinants on IRC. Our results are in line with previous findings and provide a vivid example in Western Switzerland. This paper underlines the different influence complexities of radon, and the need to communicate about it within the broader public and with construction professionals, to raise awareness.

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