Mitigation Techniques for Interior Radon in Refurbishment Work in High Radiation Areas of Galicia: An Experimental Model to Test Building Solutions

The purpose of this work was to investigate the correlation between concentrations of radon (222Rn) and radium (226Ra) in soil and to estimate the potential natural radiation hazard indices in Southern Thailand, Songkhla province, Namom district. In this study, the concentration of radon was measured by RTM1688-2 radon monitor and radium content was made using a high-resolution gamma spectrometer. A positive correlation coefficient between exhaled radon in soil gas and radium concentrations has been observed. Average concentrations of 226Ra, 232Th and 40K in soil samples were (108 ± 26), (114 ± 22) and (1081 ± 278) Bq kg−1, respectively. These values were used to estimate the radiological health hazard indices using standard analytical methods. The estimated absorbed dose rate, annual effective dose equivalent, gamma radiation hazard index and excess lifetime cancer risk are higher than world permissible limit. These values show a significant health risk due to radiation pollution in Southern Thailand.

In present study, the technique was used, including nuclear track detector type (CR-39), for appreciative concentrations uranium and radon in soil samples from Baghdad University Campus-AL-Jadiriyah utilizing a prolonged -term with a solid-state nuclear path sensor, a technique for charged particles has been developed., the radon concentrations, effective dose rate and uranium concentrations have measured in soil samples. Eight various venues from soil Baghdad University Campus have appointed. The results indicated variant values about uranium and radon concentrations, the average value for radon gas, effective dose rate and uranium concentrations was found to be 281.59 Bq/cm3, 7.09 mSv/y and 0.01 Bq/mm-2 respectively. All results appeared that concentrations for radon and uranium in soil are infra the permitted limit from (ICRP) agency which are 1100 Bq/m3 and 11.7 (mg. Kg- 1) ppm respectively. All results were comparison with the domestic and worldwide results.

Spring waters used as spas and their region may contain significant amounts of natural radionuclides. The main sources of exposure are the inhalation of radon and its decay products released from the water and soil and terrestrial gamma-radiation. In order to evaluate the potential risk of thermal regions in Bursa, located in the impact area of the NAF (North Anatolian Fault), radon and thoron concentrations in soil gas, radon concentrations in thermal waters and outdoor gamma radiation levels were measured in thermal regions that have different geological formations. The radon and thoron concentrations in soil–gas were found to vary from 2272 ± 121 to 245196 ± 3455 Bq m−3 and from 999 ± 218 to 178 848 ± 17 742 Bq m−3, respectively. The radon concentrations in thermal waters ranged from 0.99 ± 0.21 to 226.74 ± 2.51 Bq l−1 in the rainy season and from 0.26 ± 0.10 to 178.03 ± 12.86 Bq l−1 in the dry season. The measured outdoor gamma radiation levels varied from 38 to 180 nGy h−1. The gamma dose rates were found to be strong positively correlating with the radon and thoron concentrations in soil–gas. The radon and outdoor gamma radiation levels were observed to be a function of the geological formations of the area.

In this paper, nine researched studies of radon concentrations in Tanzania were reviewed by searching specified databases from various search engines, such as Web of Science, Scopus, Google Scholar, Science Direct and PubMed for the studies published between the years 2010 and mid-April 2024 in English language to establish baseline data for the current research, which focused on Tanzania’s national radon survey and radon mapping strategy. The radon prediction map was created using well-known GIS software, ArcGIS 10.3. The results show that studies were conducted in central Tanzania close to Bahi and Manyoni uranium deposits, the Northern part of Tanzania at the Buhemba Gold mine and Tanzanite mines, and southern highlands at the Mkuju uranium project and Kiwira Coal mine. From the results of this review, the highest level of indoor radon concentration of 619 ± 59 Bq/m3 was recorded in Bahi Makulu, whilst the lowest average level of 19 ± 3 Bq/m3 was observed in Manyoni town. Radon in soil was conducted in Dodoma city only, and the mean was 59.8 kBq/m3. The average mean of radon in building materials is 74.6 Bq/m3, whilst no study has been found in the literature for radon in water. The lowest and highest radon concentration levels found in mining pits are 36 ± 5 and 4171.6 Bq/m3 reported from the Kiwira coal mine and Tanzanite Merelani mine, respectively. The results of this study emphasise the need for additional research on radon across the nation and raise awareness of the dangers and causes of radon exposure. Furthermore, this paper’s results will help develop the national indoor radon database and establish a regulatory framework for radon in buildings, soil, underground mines, building materials and water.

Studies of Radon in Rocks and Soil: Techniques for Measuring Radon in Soil: Methods of Characterization of Ground for Assessment of Indoor Radon Potential at a Site (A.B. Tanner). Simple Techniques for Soil-Gas and Water Sampling for Radon Analysis (G.M. Reimer). A Preliminary Evaluation of Environmental Factors Influencing Day-to-Day and Seasonal Soil-Gas Radon Concentrations (S. Asher-Bolinder, D.E. Owen, and R.R. Schumann). Derivation of Radon Migration Rates in the Surficial Environment by use of Helium Injection Experiments (G.M. Reimer). Geologic Field Studies: Radon in Sheared Metamorphic and Igneous Rocks (L.C.S. Gundersen). The Geology and Geochemistry of Soils in Boyertown and Easton, Pennsylvania (S.S. Agard and L.C.S. Gundersen). Radon in Soil Gas Gamma-Ray Activity of Rocks and Soils at the Mulligan Quarry, Clinton, New Jersey (M.E. Henry, M.E. Kaeding, and D. Monteverde). Radon in Soil Gas Along Active Faults in Central California (C-Yu King, C. Walkingstick, and D. Basler). Radon Emanation from Uranium Mill Tailings (E.R. Landa). Estimating Radon Potential: Use of Aerial Gamma-Ray Data to Estimate Relative Amounts of Radon in Soil Gas (J.S. Duval). Regional Radon Characterizations (R.T. Peake and R.R. Schumann). Reconnaissance Approach to Using Geology and Soil-Gas Radon Concentrations for Making Rapid and Preliminary Estimates of Indoor Radon Potential (G.M. Reimer, L.C.S. Gundersen, S.L. Szarzi, and J.M. Been). Studies of Radon in Water: Introduction: A Review of the Chemical Processes Affecting the Mobility of Radionuclides in Natural Waters, with Applications (R.B. Wanty and R. Schoen). Radionuclides in Ground Water, Rock and Soil, and Indoor Air of the Northeastern United States and Southeastern Canada-A Literature Review and Summary of Data (R.T. Paulsen). Techniques for Measuring Radon in Water: Sampling and Analysis of Dissolved Radon-222 in Water by the De-Emanation Method (C. Yang). A Comparison of Two Techniques for Radon-222 Measurement in Water Samples (A. Mullin and R.B. Wanty). Field Studies of Radon in Surface and Ground Waters: Use of Radon Measurements in Carters Creek, Maury County, Tennessee, to Determine Location and Magnitude of Ground-Water Seepage (R.W. Lee and E.F. Hollyday). Geologic and Geochemical Factors Controlling Uranium, Radium-226, and Radon-222 in Ground Water, Newark Basin, New Jersey (Z. Szabo and O.S. Zapecza). Radium-226, Radium-228, and Radon-222 in Ground Water of the Chickies Quartzite, Southeastern Pennsylvania (L.D. Cecil, L.A. Senior, and K.L. Vogel). Radon in Ground Water of Carson Valley, West-Central Nevada (M.S. Lico and T.G. Rowe). Geochemistry of Ground Water and Radionuclide Mobility in Two Areas of the Reading Prong, Eastern Pennsylvania (R.B. Wanty, P.H. Briggs, and L.C.S. Gundersen). Radionuclides in the Puerco and Lower Little Colorado River Basins, New Mexico and Arizona, Before 1987 (J.R. Gray and R.H. Webb). Uranium, Radium, and Radon in Deeply Buried Sediments of the U.S. Gulf Coast (T.F. Kraemer). Radon, Helium, and Other Gases in Shallow Ground Waters of Uraniferous Holocene Alluvium, Flodelle Creek, Stevens County, Northeast Washington (J.K. Otton and G.M. Reimer). Figures.

Summary Uranium and its daughters including Ra-226 are naturally present in the Earth's crust and other environmental bodies. During decay of Ra-226 radioactive noble gas radon is produced. This gas emanates to the atmosphere from solid matrixes containing Ra-226. It causes a special problem connected with the fact that radon accumulates in the closed spaces of buildings. Increased concentrations of radon indoors in many cases are the significant source of human exposure to ionizing radiation. Radon daughters having been deposited in the airways of human lungs are the source of alpha particles which irradiates the inner surface of airways. Since radiation quality of alpha radiation is high and small volumes of tissues are being irradiated, the influence of indoor radon as a source of ionizing radiation is significant. In order to forecast indoor radon concentrations and to take necessary remedial (in existing buildings) or prevention (in new buildings) measures, the main sources of indoor radon should be known in each country or geographical region. It may be soil, building materials, water and natural gas. It has been determined that the main source of indoor radon in Lithuania is soil. Permanent investigations of radionuclide content of building materials used or manufactured in Lithuania have not revealed any building materials with concentrations of naturally occurring radionuclides exceeding maximum permitted levels determined by the Lithuanian Hygienic Standards HN 40-1994. These investigations are performed by means of gamma spectrometry using the Ge spectrometer by Oxford after sample grinding and drying. A short review of radon risk mapping techniques used in Sweden, USA, Germany and Czech Republic is presented in paper. These techniques may be used for creation of similar technique in Lithuania with corrections connected with local geology. When determining radon risk mainly two parameters should be taken into account: radium content in soil (or radon content in soil air) which is associated with the type of soil and permeability of soil. The Lithuanian system of radon risk determination is not created yet because more detailed data on radon concentrations in soil air should be collected. Data from field measurements of radon concentrations in soil air and concentrations of naturally occurring radionuclides are presented. These measurements were carried out in some potentially important from the point of view of radon risk regions of Lithuania. Concentrations of Ra-226, Th-228 and K-40 in soil have been measured by gamma spectrometer GR-256 by Exploranium on the surface layer (up to 30 cm) of soil. Concentrations of radon in soil have been measured by MARKUS 10 in the depth of 70 cm. The measurements have been performed directly without sampling and sample preparation by digging the detector of Exploranium and pumping rod of MARKUS 10 in the investigated soil. The results indicate that there are some regions in Lithuania with radon concentrations in soil air exceeding 100 kBq/m3. Though radon risk depends on soil permeability these results show that these areas may be identified as areas of medium or even high radon risk. The system for classification of building sites in terms of indoor radon risk should be created in Lithuania in order to follow requirements of Lithuanian radiation protection standards and to keep below determined action levels of indoor radon- 400 Bq/m3 in existing buildings and 200 Bq/m3 in constructed ones. Results of indoor radon measurements are presented as well. The measurements have been performed in 400 randomly selected detached houses during heating season in two lowest permanently used rooms. Duration of one measurement exceeds 3 weeks. E-PERM electrets have been used for this type of measurements. The results show that the average concentration of indoor radon in Lithuania is 55 Bq/m3. In some cases these concentrations exceed the above-mentioned action levels and approach 2000 Bq/m. It shows that indoor radon problems exist in Lithuania as in many other countries. The average concentration of indoor radon in karst region is 125 Bq/m3. It shows that special attention should be paid to such regions because conditions for increased intake of radon to buildings may exist. Indoor radon is one of the main sources of exposure in Lithuania. In some cases it may be the essential source causing tens of milisieverts of annual effective dose. It shows that the problem of indoor radon is important in Lithuania.

Uranium and its daughters including Ra-226 are naturally present in the Earth's crust and other environmental bodies. During decay of Ra-226 radioactive noble gas radon is produced. This gas emanates to the atmosphere from solid matrixes containing Ra-226. It causes a special problem connected with the fact that radon accumulates in the closed spaces of buildings. Increased concentrations of radon indoors in many cases are the significant source of human exposure to ionizing radiation. Radon daughters having been deposited in the airways of human lungs are the source of alpha particles which irradiates the inner surface of airways. Since radiation quality of alpha radiation is high and small volumes of tissues are being irradiated, the influence of indoor radon as a source of ionizing radiation is significant. In order to forecast indoor radon concentrations and to take necessary remedial (in existing buildings) or prevention (in new buildings) measures, the main sources of indoor radon should be known in each country or geographical region. It may be soil, building materials, water and natural gas. It has been determined that the main source of indoor radon in Lithuania is soil. Permanent investigations of radionuclide content of building materials used or manufactured in Lithuania have not revealed any building materials with concentrations of naturally occurring radionuclides exceeding maximum permitted levels determined by the Lithuanian Hygienic Standards HN 40-1994. These investigations are performed by means of gamma spectrometry using the Ge spectrometer by Oxford after sample grinding and drying. A short review of radon risk mapping techniques used in Sweden, USA, Germany and Czech Republic is presented in paper. These techniques may be used for creation of similar technique in Lithuania with corrections connected with local geology. When determining radon risk mainly two parameters should be taken into account: radium content in soil (or radon content in soil air) which is associated with the type of soil and permeability of soil. The Lithuanian system of radon risk determination is not created yet because more detailed data on radon concentrations in soil air should be collected. Data from field measurements of radon concentrations in soil air and concentrations of naturally occurring radionuclides are presented. These measurements were carried out in some potentially important from the point of view of radon risk regions of Lithuania. Concentrations of Ra-226, Th-228 and K-40 in soil have been measured by gamma spectrometer GR-256 by Exploranium on the surface layer (up to 30 cm) of soil. Concentrations of radon in soil have been measured by MARKUS 10 in the depth of 70 cm. The measurements have been performed directly without sampling and sample preparation by digging the detector of Exploranium and pumping rod of MARKUS 10 in the investigated soil. The results indicate that there are some regions in Lithuania with radon concentrations in soil air exceeding 100 kBq/m3. Though radon risk depends on soil permeability these results show that these areas may be identified as areas of medium or even high radon risk. The system for classification of building sites in terms of indoor radon risk should be created in Lithuania in order to follow requirements of Lithuanian radiation protection standards and to keep below determined action levels of indoor radon- 400 Bq/m3 in existing buildings and 200 Bq/m3 in constructed ones. Results of indoor radon measurements are presented as well. The measurements have been performed in 400 randomly selected detached houses during heating season in two lowest permanently used rooms. Duration of one measurement exceeds 3 weeks. E-PERM electrets have been used for this type of measurements. The results show that the average concentration of indoor radon in Lithuania is 55 Bq/m3. In some cases these concentrations exceed the above-mentioned action levels and approach 2000 Bq/m. It shows that indoor radon problems exist in Lithuania as in many other countries. The average concentration of indoor radon in karst region is 125 Bq/m3. It shows that special attention should be paid to such regions because conditions for increased intake of radon to buildings may exist. Indoor radon is one of the main sources of exposure in Lithuania. In some cases it may be the essential source causing tens of milisieverts of annual effective dose. It shows that the problem of indoor radon is important in Lithuania.

Soil radon gas in some soil types in the rainy season in Ho Chi Minh City, Vietnam

Exploring the relationship between soil degassing and seismic activity by continuous radon monitoring in the Longitudinal Valley of eastern Taiwan

Development of multi-detector soil radon measurement system based on IoT.

Radon is a naturally occurring radioactive gas which tends to build up within structures. It is therefore necessary to include techniques to mitigate radon concentration when undertaking refurbishment. The goal of this study is to assess the effectiveness of a mitigation technique based on pressurizing the interior of a building, by testing a prototype of the mitigating device, developed by Siglo 21 Consultores and the LaRUC of the University of Cantabria, under real conditions, to determine its effectiveness during refurbishment. The methodology involved installing the proposed solution in a traditional country dwelling in an area characterized by high radon concentration, on the coast of Galicia, Spain. In order to measure the effectiveness of the solution, continuous measurement sensors, set in an ionization chamber, and properly calibrated by the LaRUC laboratory, were installed. The results obtained show that pressurizing the living quarters brings about an effective reduction in the radon concentration, with a relatively simple building solution. This solution, which is compatible with the principle of minimum intervention, is seen to be especially appropriate when work is undertaken in structures recognized as heritage.

Soil-based radon investigations are of value in correlating radon production and its transportation into buildings through the processes of convection and diffusion. Such studies can help in identifying land areas that pose special concerns. We present preliminary results of soil radon gas measurements at 60 different locations in an attempt to map out the geohazard zone of the city of Muzaffarabad. The seismic geohazard microzonation for the area includes five microzones based on different hazard parameters: a very high hazard zone, a high hazard zone, a moderate hazard zone, a low hazard zone, and a safe zone. Measurements were taken with an active radon monitoring system at the depths of 30, 40, 50, and 60 cm below the ground surface. The results obtained were explained by the lithology of the area. Average soil radon gas concentrations were correlated with the depth from the ground surface and indoor radon values for the study area. No significant correlation was found between soil radon gas and meteorological parameters, however soil radon gas increases as the depth from the surface of the ground grows. The results showed a linear relation between soil radon concentrations with depth from ground surface (R2 = 0.9577). The minimum soil radon concentration (68.5 Bq/m3) was found at a depth of 30 cm in the very high hazard zone, the maximum value (53.300 Bq/m3) at a depth of 60 cm in the seismically safe zone. Measured soil gas radon concentrations at depths of 30, 40, 50, and 60 cm were mapped for high, moderate, and low radon concentrations. Elevated soil radon gas concentrations were found in the safe zone, otherwise considered to be suitable for any type of construction.

19th International Conference on Nuclear Tracks in Solids, Besançon, France, 31 August-4 September 1998

Study on active tectonic faults using soil radon gas method in Viet Nam

On-line monitoring of soil radon (222Rn) concentration system was constructed on one of the main active fault zone of East Anatolian Fault System (EAFS) in Turkey. The preliminary results, observed during the second part of 2004 and first part of 2005 is presented. During the monitoring of soil radon concentration, numerous anomalies that equal or twice standard deviation were observed. In addition, the variation of the radon concentration was examined between the mean values and plus/minus two standard deviations and any increase in radon concentration above this limit was assumed to be 222Rn anomalies. These anomalies usually appeared between a few days or weeks before the earthquakes occurrence. The obtained data were also compared as considered respect to the earthquakes occurred in a 100 km radius of the fault system.