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| Titel |
Low-cost NORM concentrations measuring technique for building materials of Uzbekistan |
| VerfasserIn |
Akmal Safarov, Askar Safarov, Askarali Azimov, Iain G. Darby |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250136810
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| Publikation (Nr.) |
 EGU/EGU2016-17932.pdf |
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| Zusammenfassung |
| Concentrations of natural radionuclides of building materials are important in order to estimate exposure of humans to radiation, who can spend up to 80% of their time indoors. One of the indicators of building materials’ safety is the radium equivalent activity, which is regulated by national and international normative documents [1,2,3]. Materials with Ra(eq) =< 370 Bq/kg are considered to be safe [4,5]. We have studied the possibility of performing express analysis of building materials samples without ageing. Long measurement times including ageing of samples are major constraints for performing large number of analyses [6]. Typically ageing of samples and analysis is 40 days. Gamma-spectrometric analysis of brick, crushed stone, red sand, granite, white marble and concrete cubes was performed both before and after ageing of samples (10, 20, 30 and 40 days). Measurement times of samples were 1, 3, 6 and 12 hours. Samples were measured in 1 liter Marinelli beaker geometry, using NaI(Tl) spectrometers with crystal sizes 2.5 x 2.5 in and 3.1 x 3.1 in. Efficiency calibration of spectrometers was done using certified volumetric (1 liter Marinelli beaker) Ra-226, Th-232 and K-40 sources filled with silica sand and density 1,7 kg/l. Herein we present results indicating that one hour measuring may be sufficient for samples in 1 liter Marinelli beakers offering prospect of significant time and cost improvements.
References:
1. NEA-OECD (1979): Exposure to radiation from natural radioactivity in building materials. Report by Group of Experts of the OECD Nuclear Energy Agency (NEA) Paris
2. STUK (Radiation and Nuclear Safety Authority) (2003): The radioactivity of building materials and ash. Regulatory Guides on Radiation Safety (ST Guides) ST 12.2 (Finland) (8 October 2003)
3. GOST 30108-94 (1995): Building materials and elements. Determination of specific activity of natural radioactive nuclei. Interstate Standard.
4. Krisiuk E.M. et al., (1971). A study on Radioactivity in Building Materials (Leningrad: Research Institute for radiation Hygiene)
5. Beretka, J., & Mathew, P. J. (1985). Natural radioactivity of Australian building materials, waste and by-products. Health Physics, 48, 87-95.
6. Uosif M.A.M. (2014). Estimation of Radiological Hazards of Some Egyptian Building Materials Due to Natural Radioactivity. International Journal of u- and e- Service, Science and Technology. Vol.7, No.2 (2014), pp.63-76 |
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