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Assessment of radon exhalation rate, radon concentration and annual efective dose of some building materials samples used in Yemen

Saleh Emran Eisa, Al-Sobahi Aref Mohammed Ahmed, El-Fiki Soad Abed Elmonem

Acta Geophysica

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2021

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Vol. 69, no. 4

1325--1333

EN

Radon gas has been recognized as one of the health hazards to humans. Building materials used for the construction of houses, which are considered as one of the major sources of this gas in indoor environments. The radon exhalation rate, radon concentration as well as the annual efective dose for 46 samples of building materials (granite, ceramic, marble, mosaic, rocks, gypsum, block and red brick) used in Yemen were measured using two methods. The can technique, containing CR-39 solid-state detector, and active method containing AlphaGuard detector were used. The results obtained from passive and active techniques were found in good agreement. The results showed that the highest values of radon exhalation rate, radon concentration and the annual efective dose indoor and outdoor were 0.93 ± 0.020 Bqm-2 h-1, 186.48 ± 3.73 Bqm-3, 4.7 ± 0.141 and 1.76 ± 0.053 mSvy-1 for granite samples, whereas the lowest values were 0.0076 ± 0.001 Bqm-2 h-1, 1.51 ± 0.03 Bqm-3, 0.04 ± 0.001 and 0.01 ± 0.001 mSvy-1 for the ceramic samples. The results also showed that the radon exhalation rate, as well as the annual efective dose, was found below the world average values of 57.600 Bq m-2 h-1, 1100 μSv y-1 with exception of some samples. The values of radon concentrations for granite samples were in the range of activity levels from 200 to 600 Bq m-3 recommended by (ICRP, 1994).

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Rapid estimation of environmental radioactivity surrounding Xiangshan uranium deposits, Jiangxi province, Eastern China

Gan N., Cen K., Ye R., Li T.

Nukleonika

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2018

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Vol. 63, No. 4

113--121

EN

The surveys of terrestrial gamma dose rate, radon concentration indoor and in water and specific activity of radionuclides of soil were carried out in 14 villages and a town in Xiangshan uranium deposit and surrounding area, Jiangxi province, Eastern China, in 2017–2018, using a scintillator dosemeter, an ionization chamber and a high-purity germanium gamma spectrometer to study radiation status in these places after remediation. A radioactive hot spot was discovered in a village near the mining office, where specific activity of 238U, 226Ra, 232Th and 137Cs of soil was as high as 1433 ± 76 Bq/kg, 1210 ± 62 Bq/kg, 236 ± 13 Bq/kg and 17 ± 1.1 Bq/kg, respectively. The dose rate on a waste rock heap was about 2423 nGy/h. Approximately 50% of the houses in a village near the uranium mining site had radon concentrations that exceeded 160 Bq/m3 . There was a significant positive correlation between indoor radon concentration and outdoor gamma dose rate (R2 = 0.7876). The abnormal radon concentration was observed in a rising spring sample providing residents with tap water up to 127.1 Bq/l. Four tap water samples and three of five well water samples exceeded the limit of radon concentration of drinking water in China (11.1 Bq/l). The mean annual effective doses from gamma dose rate data were 0.86 mSv/y and 1.13 mSv/y for indoor radon. The study shows that there are some radioactively contaminated places surrounding the Xiangshan uranium mine. The local outdoor dose rate averages may be used to estimate local indoor radon concentrations.

3

Radioactivity of some building and raw materials used in Croatia

Sofilić T., Barišić D., Sofilić U., Đuroković M.

Polish Journal of Chemical Technology

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2011

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Vol. 13, nr 3

23-27

EN

In the present study, the activity concentrations of 226Ra, 232Th, 40K in some building and raw materials used in Croatia were measured by using a gamma-ray spectrometer with the HPGe detector. The average activity concentrations of the studied different building and raw materials ranged from 11.6 š 1.7 (concrete) to 251.2 š 25.7 Bqkg-1 (GBFS), 14.0 š 2.7 (concrete) to 54.4 š 8.3 (coal fly ash) and 147.2 š 19.0 (concrete) to 773.7 š 82.0 Bqkg-1 (tuff) for 226Ra, 232Th and 40K, respectively. Radium equivalent activity, activity concentration index, absorbed gamma dose rate indoor due to the external exposure and corresponding annual effective dose were determined to estimate the exposure risk arising due to the use of these building and raw materials.

4

Natural radioactivity in building materials in Iran

Mehdizadeh S., Faghihi R., Sina S.

Nukleonika

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2011

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Vol. 56, No. 4

363-368

EN

This work presents a comprehensive study of natural radioactivity in building materials used in Iran. For this purpose, 177 samples of five types of building material, i.e. cement, gypsum, cement blocks, gravel and brick, were gathered from different regions of the country and analyzed by gamma spectroscopy to quantify radioactivity concentrations using a high purity germanium (HPGe) detector and a spectroscopy system. According to the results of this investigation, cement samples had maximum values of the mean Ra-226 and Th-232 concentrations, 39.6 and 28.9 Bq/kg, respectively, while the lowest value for mean concentration of these two radionuclides were found in gypsum samples 8.1 and 2.2 Bq/kg, respectively. The highest (851.4 Bq/kg) and lowest (116.2 Bq/kg) value of K-40 mean concentration were found in brick and gypsum samples, respectively. The absorbed dose rate and the annual effective dose were also calculated from the radioactivity content of the radionuclides. The results show that the maximum values of dose rate and annual effective dose equivalent were 53.72 nGy/h and 0.37 mSv/y in brick samples. The radium equivalent activities Req calculated were below the permissible level of 370 Bq/kg for all building materials. The values of hazard indexes were below the recommended levels, therefore, it is concluded that the buildings constructed from such materials are safe for the inhabitants. The results of this study are consistent with the results of other investigations in different parts of the world.

5

Moc dawki promieniowania gamma w kamieniołomach obrzeżenia Górnośląskiego Zagłębia Węglowego.

Lizurek G.

Prace Naukowe Instytutu Górnictwa Politechniki Wrocławskiej. Konferencje

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2007

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Vol. 120, nr 49

197-206

PL

W rejonie obrzeżenia Górnośląskiego Zagłębia Węglowego (GZW) oraz w obrębie GZW odsłaniają się skały o różnorodnym wieku i genezie, które od średniowiecza są wydobywane w kamieniołomach. Poziom tła promieniowania jonizującego związany z zawartością radionuklidów w wydobywanych skałach jest zróżnicowany, co wykazały wcześniejsze badania. W związku z tym istotne jest oszacowanie mocy dawki promieniowania gamma, na jakie mogą być narażeni pracownicy czynnych kamieniołomów badanego obszaru. W niniejszej pracy oszacowane zostały moce dawek outdoor pochłoniętej w powietrzu i efektywnej promieniowania gamma oraz średnia roczna dawka efektywna promieniowania gamma na całe ciało pracownika kamieniołomu. Do szacowania użyto wyników pomiarów w metodyce in situ promieniowania gamma odsłaniających się w badanych kopalniach surowców skalnych. Poziom szacowanych mocy dawek oraz dawki rocznej nie przekraczają średnich dla populacji światowej, jednak stanowią istotny wkład w roczną dawkę na całe ciało człowieka otrzymywaną ze źródeł naturalnych.

EN

Borders of Upper Silesian Coal Basin are characterized by various levels of gamma ray background radiation of outcropping rocks. Most of these rocks are exploited in quarries. Important question is the level of absorbed and effective dose rates in these mines. In this work gamma ray dose rate absorbed in the air, gamma ray outdoor effective dose rate for workers body and annual gamma ray effective dose were estimated. Base of that estimation were the results of direct in situ measurements of gamma ray background radiation level of ^'K as well as uranium and thorium series radionuclides in outcropping and exploited rocks. Levels of the effective dose rates and the annual effective dose are lower than average dose rates and the annual dose for worldwide and Poland population. It can be emphasized that there is no radiation hazard for workers in studied quarries. But these estimated effective dose rates from natural radionuclides are significant part of the whole effective dose rate for workers in studied quarries.