RESULTS OF RADON INSPECTION OF SETTLEMENTS COMPROMISED DUE TO DISPOSAL OF RADIOACTIVE WASTE INTO THE TECHA RIVER

During past decades, specialists perform an epidemiological observation of the population exposed to the impact of radioactive discharges into the Techa River. The Techa River cohort studies have identified excess cases of leukemia and solid cancers associated with radiation exposure. At the same time natural sources of radiation, such as radon and its decay products, known to be significant human radiation exposure factor, are not sufficiently studied on this territory. The purpose of the study is to assess the mean value and the distribution indices of radon concentration in 14 settlements affected by radioactive contamination. Radon inspection in settlements located on the Techa River (Chelyabinsk and Kurgan regions) was executed. The measurements were performed in 511 dwellings. For radon inspection there were applied detectors based on LR-115 Kodak Track. The analysis shows the sample both to be representative and allow to estimate radon exposure for inhabitants. The average radon concentration in dwellings is 150 Bq/m3, which results in an annual effective dose of 11 mSv. The estimated number of dwellings with radon concentrations above ECC radon action level 200 Bq/m3 is 19. The factors affecting indoor radon accumulation were established. The radiation dose due to the inhalation of radon, accumulated over a long period of time, seems to be generally comparable to doses associated with the radioactive discharges into the Techa River during the 1949-1956.

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The Italian Survey as the Basis of the National Radon Policy

Radiation Protection Dosimetry ◽

10.1093/oxfordjournals.rpd.a082409 ◽

1994 ◽

Vol 56 (1-4) ◽

pp. 1-4 ◽

Cited By ~ 2

Author(s):

F. Bochicchio ◽

G. Campos-Venuti ◽

C. Nuccetelli ◽

S. Piermattei ◽

S. Risica ◽

...

Keyword(s):

Social Factors ◽

Radon Concentration ◽

Ad Hoc ◽

Indoor Radon ◽

Mean Value ◽

The Political ◽

Indoor Radon Concentration ◽

Radon Exposure ◽

Italian Survey ◽

Industrialised Countries

Abstract One of the most important goals of the Italian survey, initiated in 1989, was to promote ad hoc policies to reduce radon exposure of the population. In the survey a statistical representative sample of 5000 dwellings was chosen; two six-month measurements were made of the indoor radon concentration, in combination with one six month measurement of gamma exposure. The results of the radon concentration measurements are reported here they refer to 80% of the sample. The annual mean value was 81.5 Bq.m-3, which is higher than the reported for other industrialised countries. The survey was widely accepted by the families and provided an opportunity to collect information on families and their habits, as well as on the characteristics of the dwellings. The data will make it possible to evaluate the number of houses above a given level. It is up to the political authorities to define such a level on the basis of these data and the economic and social factors.

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

Scientific Reports ◽

10.1038/s41598-021-88904-2 ◽

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.

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Use of radon barriers to reach an acceptable radon level

E3S Web of Conferences ◽

10.1051/e3sconf/202017205003 ◽

2020 ◽

Vol 172 ◽

pp. 05003

Author(s):

Torben Valdbjørn Rasmussen ◽

Thomas Cornelius

Keyword(s):

Indoor Air ◽

Radon Concentration ◽

Indoor Radon ◽

Ventilation Rate ◽

Test Method ◽

Single Family ◽

Indoor Radon Concentration ◽

Radon Exposure ◽

Air Penetration ◽

Family House

A method is presented for theoretically estimating the necessary airtightness of a radon barrier. Radon barriers are used to balance the indoor radon concentration. To balance radon at an acceptable level, for a given ventilation rate for indoor air, a barrier must fulfil the requirements for airtightness and the indoor-air radon penetration from the soil, which is determined by the radon concentration in the soil gas. The method identifies the optimal radon barrier for a building. Ten different radon barriers are evaluated. Barriers include system solutions based on materials such as bitumen-based radon blockers, wet-room membranes, reinforced fix mortar pastes, and polyethylene membranes. The barriers are tested using a modified version of the test method NBI 167/02 radon membrane: test of airtightness. The radon barriers are evaluated for a typical building construction for a single-family house with radon exposure from the ground. An acceptable radon concentration of 100 Bq/m3 in indoor air is used in combination with a number of higher radon levels. The different radon barriers are evaluated in accordance with their ability to prevent air penetration from the ground. Furthermore, how mounting a barrier can affect the durability of a building is discussed, as the measures may create a far more vulnerable building.

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

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17082813 ◽

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.

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A finite element model development for simulation of the impact of slab thickness, joints, and membranes on indoor radon concentration

Journal of Environmental Radioactivity ◽

10.1016/j.jenvrad.2017.07.006 ◽

2017 ◽

Vol 177 ◽

pp. 280-289 ◽

Cited By ~ 10

Author(s):

E. Muñoz ◽

B. Frutos ◽

M. Olaya ◽

J. Sánchez

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Radon Concentration ◽

Indoor Radon ◽

Model Development ◽

Element Model ◽

Slab Thickness ◽

Indoor Radon Concentration ◽

The Impact

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Construction a process to measurement the indoor radon concentration

Science and Technology Development Journal ◽

10.32508/stdj.v16i3.1619 ◽

2013 ◽

Vol 16 (3) ◽

pp. 53-60

Author(s):

Hien Thi To ◽

Nguyen Thao Nguyen ◽

Huy Huu Duong

Keyword(s):

Lung Cancer ◽

Exposure Time ◽

Radon Concentration ◽

Indoor Radon ◽

Construction Process ◽

Indoor Radon Concentration ◽

Radon Exposure ◽

Indoor Location ◽

Radon Inhalation ◽

Radon Concentrations

Radon is a naturally radioactive gas , but it causes lung cancer to humans. The risk of lung cancer due to radiation depends on the amount of radon inhalation and radon exposure time. In Vietnam, radon concentrations are usually determined by RAD7, however RAD7 just showed the immediate values of radon, and have to regularly calibrate it. The construction process to determine the accumulates indoor radon concentration by detector CR- 39 in order to be widely used in the study of environmental pollution, especially the study of health risks of radon for humans and mapping radon pollution. Detector CR - 39 is placed in a 7 cm - plastic holder, and in exposure time, the holders were covered with glass fiber filter paper ∅ 47mm on the bottom of the detector to avoid the exposure of dust. Then it is hung in the indoor location as Vietnam Standard 7889:2008. After 3 months, holders are returned to a laboratory, and CR - 39 will be soaked in 6M NaOH at 700C. Indoor radon concentrations will be proportional to the density traces obtained on CR-39. The study uses an radium 226 source of the NIST (National Institute for Standards and Technology) with the released radon coefficient : f = 0.891 ± 0.015. Results show the calibration factor K is 4.533 ± 0.218 [(Bq.m-3. day)]/(tracks / CR-39)]. Using K factor, we can determine the cumulative indoor radon concentration.

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Indoor radon assessment in kindergartens: towards a national action plan

Brazilian Journal of Radiation Sciences ◽

10.15392/bjrs.v9i2.1234 ◽

2021 ◽

Vol 9 (2) ◽

Author(s):

Danila Carrijo da Silva Dias ◽

Nivaldo Carlos Da Silva ◽

Wanilson Luiz Silva ◽

Marcos Vinícius Rodrigues

Keyword(s):

Indoor Radon ◽

Action Plan ◽

Construction Materials ◽

Mean Value ◽

High Variability ◽

Local Perception ◽

Geometrical Mean ◽

Materials Used ◽

National Programs ◽

The Impact

The study presents the results of indoor radon monitoring of 342 public kindergarten rooms of a Brazilian municipality within a region featuring high natural radioactivity. Facility characterization local perception assessment were also conducted. Rooms were monitored by exposure of ATD detectors for an average 356 days. Monitoring resulted in arithmetic and population weighted means of 83 and 82 Bq m-3 respectively, while a geometrical mean value of 61 Bq m-3 was estimated. Concentrations ranged between < 3 and 697 Bq m-3 while 8.1% of rooms presented values above 200 Bq m-3 (in different units), where similarities in construction materials used in floors were noted. High variability was observed among regions, CEI units within a region and even rooms within a unit. The collected data on room ventilation elucidated challenges to large monitoring programs when evaluating the impact of human habits and window characteristics in results. The high variability of results poses challenges to the establishment of national programs in large and diverse areas such as Brazil. The first indoor radon study in children facilities in the country represents an important step towards it.

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Comparison of Predicted and Measured Variations of Indoor Radon Concentration

Radiation Protection Dosimetry ◽

10.1093/oxfordjournals.rpd.a080276 ◽

1988 ◽

Vol 24 (1-4) ◽

pp. 231-235 ◽

Cited By ~ 20

Author(s):

H. Arvela ◽

A. Voutilainen ◽

I. Mäkeläinen ◽

O. Castrén ◽

K. Winqvist

Keyword(s):

Seasonal Variations ◽

Radon Concentration ◽

Pressure Difference ◽

Indoor Radon ◽

Indoor Radon Concentration ◽

Entry Rate ◽

Concrete Walls ◽

Factors Affecting ◽

Air Infiltration ◽

Concentration Ratios

Abstract Prediction of the variations of indoor radon concentration were calculated using a model relating indoor radon concentration to radon entry rate, air infiltration and meteorological factors. These calculated variations have been compared with seasonal variations of 33 houses during 1-4 years, with winter-summer concentration ratios of 300 houses and the measured dirunal variation. In houses with a slab in ground contact the measured seasonal variations are quite often in agreement with variations predicted for nearly pure pressure difference driven flow. The contribution of a diffusion source is significant in houses with large porous concrete walls against the ground. Air flow due to seasonally variable thermal convection within eskers strongly affects the seasonal variations within houses located thereon. Measured and predicted winter-summer concentration ratios demonstrate that, on average, the ratio is a function of radon concentration. The ratio increases with increasing winter concentration. According to the model the diurnal maximum caused by a pressure difference driven flow occurs in the morning, a finding which is in agreement with the measurements. The model presented can be used for differentiating between factors affecting radon entry into houses.

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Long-Lived Radon Decay Products as a Long-Term Radon Exposure Indicator

Radiation Protection Dosimetry ◽

10.1093/oxfordjournals.rpd.a082435 ◽

1994 ◽

Vol 56 (1-4) ◽

pp. 123-126 ◽

Cited By ~ 9

Author(s):

C. Samuelsson ◽

L. Johansson

Keyword(s):

Indoor Radon ◽

Radon Exposure ◽

Decay Products ◽

Decay Series ◽

Radon Diffusion ◽

Radon Daughter ◽

Radon Decay ◽

Low Activity ◽

Long Term Studies

Abstract The different members of the uranium decay series have distinct roles to play in the scenario of indoor radon. The 222Rn gas is the airborne carrier of the dose giving short-lived decay products. These transform into long-lived daughters (LRnD) of low activity, useful as retrospective radon tracers. Porous objects constitute volume traps for LRnD via radon diffusion, while surfaces trap LRnD through alpha recoil implantation. Only when the build-up of LRnD activity proceeds undisturbed over many years, do we have a system which is potentially useful for retrospective radon/radon daughter exposure studies. The feasibility of using LRnD in humans and in volume and surface traps as radon retrospective monitors is discussed. It is concluded that only surface implantation sinks are potentially well suited for long-term studies at radon levels met in dwellings.

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