64 research outputs found
Active and passive radon concentration measurements and first-step mapping in schools of Banja Luka, Republic of Srpska
Radon concentration measurements were performed in all 25 primary schools in Banja Luka city, the capital of Republika Srpska, during 2011 and 2012, using both active RAD7 continual radon measuring instruments and CR-39 passive (commercially known as Gamma) detectors. The two complimentary methods were employed not only to obtain annual averages, but also to study the dynamics of radon concentration changes during the week. For each school, average and temporal variations of radon concentrations were analysed, taking into consideration local geology, building materials and meteorological conditions. The influence of forced ventilation, caused by frequent opening of doors and windows during working hours, with typical dawn and weekend peaks is evident in most but not all schools. Elevated levels of radon concentration (>400 Bq m-3) were found in a few schools using both methods. Although high correlation factor of 0.8 between passive and active methods was found, still short-time (one-week) measurements cannot be used for annual estimation of radon activity but screening one. Thus, the conclusion concerns only long time measurements as valid indicator of annual radon activity.JRC.E.8-Nuclear securit
European data portal for radioactivity in the environment
A prototype of a web tool to report all environmental samples collected via the following activities EURDEP, REM database and European Atlas of Natural Radiation. This tool must become a part of the REM website and enable users to search, aggregate and export the natural radioactivity data in the view of interactive maps, PDF downloadable.JRC.G.10-Knowledge for Nuclear Security and Safet
The first version of the Pan-European Indoor Radon Map
A hypothetical Pan-European Indoor Radon Map has been developed using summary statistics estimated from 1.2 million indoor radon samples. In this study we have used the arithmetic mean (AM) over grid cells of 10 km10 km to predict a mean indoor radon concentration at ground-floor level of buildings in the grid cells where no or few data (N < 30) are available. Four interpolation techniques have been tested: inverse distance weighting (IDW), ordinary kriging (OK), collocated cokriging with uranium concentration as a secondary variable (CCK), and regression kriging with topsoil geochemistry and bedrock geology as secondary variables (RK). Cross-validation exercises have been carried out to assess the uncertainties associated with each method. Of the four methods tested, RK has proven to be the best one for predicting mean indoor radon concentrations; and by combining the RK predictions with theAMof the grids with 30 or more measurements, a Pan-European Indoor Radon Map has been produced. This map represents a first step towards a European radon exposure map and, in the future, a radon dose map
Some results of a radon survey in 207 Serbian schools
In this paper the results of radon concentration measurements performed in 207 schools in 7 communities of Southern Serbia are presented. The annual radon concentration varied from 17 Bqm-3 to 428 Bq m-3 with a median value of 96 Bq m-3. The arithmetic mean (AM) of the 207 annual averages was 118 Bq m-3 with a standard deviation (SD) of 78 Bq m-3. The best distribution fitting of radon concentration by log-normal function was obtained. The log-normal parameters are the following: geometric mean (GM) = Bq m-3, geometric standard deviation (GSD) = 1.9. In addition, a spatial distribution of the indoor radon concentration over the investigated areas is observed.JRC.E.8-Nuclear securit
Similarities and differences between radon surveys across Europe: results from MetroRADON questionnaire
Background: As a major cause of lung cancer after smoking, indoor radon is a hazard for human health. Key steps of radon surveys are numerous and include metrology, survey design, development of maps, communication of results to stakeholders, etc. The Council Directive 2013/59/EURATOM introduced new challenges for European Union Member States, such as the identification of radon priority areas, which calls for efforts to improve all the key steps involved in radon surveys.
Objective: This study aims to compare existing radon measurement procedures between different European countries and to use the results to optimize the consistency of indoor radon data across Europe.
Design: A questionnaire was developed and sent to more than 70 European institutions working in this field to collect information on indoor radon surveys carried out in the respective countries, in order to identify the rationale and methodologies used.
Results: A total of 56 questionnaire forms on indoor radon surveys were completed and returned by universities, research institutions, and competent authorities on national and regional surveys from 24 European countries. The replies have been analyzed, and the main findings have been reported, although these replies did not allow to answer all the questions about comparability.
Conclusions: From the replies given by the respondents, there is evidence that European indoor radon surveys are comparable regarding measurement methods but not comparable regarding the survey design. Comparability regarding data management, statistical treatment, aggregation, and mapping is unclear on the basis of the replies putting in evidence the need of further information
European Atlas of Natural Radiation
Natural ionizing radiation is considered as the largest contributor to the collective effective dose received by the world population. The human population is continuously exposed to ionizing radiation from several natural sources that can be classified into two broad categories: high-energy cosmic rays incident on the Earthâs atmosphere and releasing secondary radiation (cosmic contribution); and radioactive nuclides generated during the formation of the Earth and still present in the Earthâs crust (terrestrial contribution). Terrestrial radioactivity is mostly produced by the uranium and thorium radioactive families together with potassium. In most circumstances, radon, a noble gas produced in the radioactive decay of uranium, is the most important contributor to the total dose.
This Atlas aims to present the current state of knowledge of natural radioactivity, by giving general background information, and describing its various sources. This reference material is complemented by a collection of maps of Europe displaying the levels of natural radioactivity caused by different sources.
It is a compilation of contributions and reviews received from more than 80 experts in their field: they come from universities, research centres, national and European authorities and international organizations.
This Atlas provides reference material and makes harmonized datasets available to the scientific community and national competent authorities. In parallel, this Atlas may serve as a tool for the public to:
⢠familiarize itself with natural radioactivity;
⢠be informed about the levels of natural radioactivity caused by different sources;
⢠have a more balanced view of the annual dose received by the world population, to which natural radioactivity is the largest contributor;
⢠and make direct comparisons between doses from natural sources of ionizing radiation and those from man-made (artificial) ones, hence to better understand the latter.JRC.G.10-Knowledge for Nuclear Security and Safet
European Atlas of Natural Radiation
Natural ionizing radiation is considered as the largest contributor to the collective effective dose received by the world population. The human population is continuously exposed to ionizing radiation from several natural sources that can be classified into two broad categories: high-energy cosmic rays incident on the Earthâs atmosphere and releasing secondary radiation (cosmic contribution); and radioactive nuclides generated during the formation of the Earth and still present in the Earthâs crust (terrestrial contribution). Terrestrial radioactivity is mostly produced by the uranium and thorium radioactive families together with potassium. In most circumstances, radon, a noble gas produced in the radioactive decay of uranium, is the most important contributor to the total dose.This Atlas aims to present the current state of knowledge of natural radioactivity, by giving general background information, and describing its various sources. This reference material is complemented by a collection of maps of Europe displaying the levels of natural radioactivity caused by different sources. It is a compilation of contributions and reviews received from more than 80 experts in their field: they come from universities, research centres, national and European authorities and international organizations.This Atlas provides reference material and makes harmonized datasets available to the scientific community and national competent authorities. In parallel, this Atlas may serve as a tool for the public to: ⢠familiarize itself with natural radioactivity;⢠be informed about the levels of natural radioactivity caused by different sources;⢠have a more balanced view of the annual dose received by the world population, to which natural radioactivity is the largest contributor;⢠and make direct comparisons between doses from natural sources of ionizing radiation and those from man-made (artificial) ones, hence to better understand the latter.Additional information at: https://remon.jrc.ec.europa.eu/About/Atlas-of-Natural-Radiatio
Exploring European Thematic Maps for Radioecology Modelling
Geographic Information Systems (GIS) have been widely used for ecological modelling as they have been designed to simulate spatial aspects of our environment. These tools have also been extensively adapted to radioecology to model the behaviour of radionuclides in the environment. Among other applications, GIS have been used to map radioactive deposition patterns, assess the transfer of radionuclides in food chains and calculate external radiation doses. The apparent simplicity of these tools, their convincing approach and their aesthetic output can easily delude the users by hiding the many simplifications made in modelling the environment. Therefore, it is not a surprise that new research activities in the field of GIS largely focus on data uncertainty and error propagation.
Radioecological modelling by means of GIS is particularly exposed to errors because it depends largely on transfer factors (TFs). These are defined as the ratio of the concentration of a radionuclide in a receiving compartment to the concentration in the source compartment. Hence, whether the models are able to predict correctly the behaviour of radionuclides in the environment depends largely on the quality of the thematic maps used to describe these compartments. Thus it appears that the fate of GIS in the field of radioecology will depend largely on developing datasets that are appropriate for describing the various ecological compartments.
In this paper, we briefly review radioecological studies made by other authors who used GIS. Then we discuss the use and needs of thematic maps for radioecological modelling, with an emphasis on soil maps derived from the recently released European Soil Data Base. The latter are expected to play an important role in terrestrial radioecology, especially for studies at a continental scale.
KEYWORDS: Radioecology, GIS, thematic maps, soil maps, modellingJRC.H.4-Transport and air qualit
Investigations on Indoor Radon in Austria, part 2: Geological Classes as Categorical External Drift for Spatial Modelling of the Radon Potential
Geological classes are used to model the deterministic (drift or trend) component of the Radon potential (Friedmann's RP) in Austria. It is shown that the RP can be grouped according to geological classes, but also according to individual geological units belonging to the same class. Geological classes can thus serve as predictors for mean RP within the classes. Variability of the RP within classes or units is interpreted as the stochastic part of the regionalized variable RP; however, there does not seem to exist a smallest unit which would naturally divide the RP into a deterministic and a stochastic part. Rather, this depends on the scale of the geological maps used, down to which size of geological units is used for modelling the trend. In practice, there must be a sufficient number of data points (measurements) distributed as uniformly as possible within one unit to allow reasonable determination of the trend component. 2007 Elsevier Ltd. All rights reserved.
Keywords: Indoor radon; Radon potential; Geology; Mapping; GeostatisticsJRC.H.4-Transport and air qualit
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