• Title/Summary/Keyword: 수중라돈

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Measurement of $^{222}Rn$ in ground water with low-level Liquid Scintillation Counter and pulse shape analysis (저준위 액체섬광계수기와 파형분석법을 이용한 지하수중의 $^{222}Rn$ 측정)

  • Jo Su-Yeong;Yun Yun-Yeol;Lee Gil-Yong;Kim Yong-Je
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2006.04a
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    • pp.319-323
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    • 2006
  • 파형분석(PSA) 기능과 백그라운드 낮고 계측효율이 높은 장점을 가지고 있는 저준위 액체섬광계수기를 이용하여 지하수중의 $^{222}Rn$ 측정을 위한 최적 분석조건을 확립하였다. 라돈분석을 위해 섬광용액 HiSafe 3 12 ml를 사용하여 물시료 8 ml 내 $^{222}Rn$ 을 측정하였다. 라돈은 딸핵종과의 방사평형을 위해 3시간동안 방치한 후 계측하였다. 최적 파형분석 (PSA) 준위는 100 이었다. $^{222}Rn$의 계측효율은 $^{226}Ra$ 표준시료를 동일 조건으로 제조한 후 약 20일 이상 방치한 다음 측정하여 결정하였으며 측정효율은 약 $91.6{\pm}3.6%$ 이었다. 동일 시료의 라돈 추출실험 재현성은 2 % 이내이었다. 계측시간 10시간을 기준으로 바탕값은 0.035 cpm 이었고 300분 계측시 검출하한값은 0.11 Bq/L 이었다.

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Distribution of $^{222}Rn$ Concentration in Seoul Subway Stations (서울지역 지하철역의 라돈농도 분포 특성)

  • Jeon, Jae-Sik;Kim, Dok-Chan
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.6
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    • pp.588-595
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    • 2006
  • Indoor radon($^{222}Rn$) concentrations of subway stations in Seoul area were measured to survey the environmental indoor radon levels and to identify sources of radon. The radon concentration of indoor air by method of long-term measuring with a-track detector were surveyed at 232 subway stations from 1998 to 2004. And the radon concentration in ground-water was measured with a method of alpha particle counting. To trace main source of radon, 8 out of 232 stations were selected and their radon concentrations in tunnel and on platform were analyzed. Total geometric mean and arithmetic mean of radon concentrations in all stations from 1998 to 2004 were $1.40{\pm}1.94pCi/L,\;1.65{\pm}1.07$ respectively. Geometric means of radon concentrations on platform and concourse were $1.54{\pm}1.96pCi/L,\;1.23{\pm}1.88pCi/L$ respectively, with higher concentration at the platform than at the concourse. The geological structure was significantly correlated to the indoor radon concentration in subway stations region. Radon concentrations of adjacent tunnel and ground-water of subway station was significantly correlated to the indoor radon concentration in subway stations. And There was a significant difference in radon concentration, depending on the depth levels in platform of subway stations(p<0.05).

Characterization of Radon Concentration in Public Facilities (다중이용시설의 실내공기중 라돈농도분포 특성)

  • 김윤신;홍승철;이철민;박원석;이태형;전형진;조정현
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.529-530
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    • 2003
  • 우라늄(U-238)의 붕괴과정에서 생성되는 라돈(Rn-222)은 다른 물질과 화학적으로 결합 또는 부착하지 않는 불활성 기체이고 상대적으로 긴 반감기를 갖고 있기 때문에 충분한 시간 동안 공기중에 머물러 있으므로 다른 자연방사선원에 비하여 라돈과 라돈자손에 의한 일반인의 자연방사선피폭 기여도가 가장 높다(Jamil K. 1997). 이미 세계 여러 나라에서는 라돈피폭에 기인한 건강상의 위해를 인식하여 주택을 비롯한 여러 생활공간의 실내 및 음용수 중의 라돈농도에 대한 대규모적인 측정을 수행하고 있으며, 그 결과 미국 내 상당수의 주택이 미국 환경청에서 권고치(action level)로써 권고하고 있는 150 Bq/m3(실내공기중)와 11.100 Bq/m3(음용수중)응 초과하는 것으로 나타났다(U,S,EPA, 1992).(중략)

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대전지역 지열별 지하수중의 라돈 및 우라늄 분포 특성연구

  • Yun Yun-Yeon;Jo Su-Yeong;Lee Gil-Yong;Kim Yong-Je
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2005.04a
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    • pp.300-303
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    • 2005
  • 대전지역 화강암지대에 존재하는 75개 지하수를 5개 지역구에서 채취하였으며, 상ㅁ하반기 동안 2차례 시료를 채취하여 건기와 우기후의 라돈 및 우라늄 농도를 분석하였다. 5개 지역에 대한 라돈과 우라늄의 평균 농도는 유성구에서 270.9 Bq/L, $43.8{\mu}g/L$ 였으며, 동구의 경우 41.3 Bq/L, $4.9{\mu}g/L$, 대덕구는 131.8 Bq/L, $54.3{\mu}g/L$, 중구의 경우 44.0 Bq/L, $8.1{\mu}g/L$ 그리고 서구는 112.9 Bq/L, $0.4{\mu}g/L$ 이었다. 라돈과 우라늄의 함량은 건기가 우기후에 비해 대체로 높게 나타났으며 건기시의 평균값은 라돈은 $253{\pm}14\;Bq/L$ 우라늄은 $63{\mu}g/L$ 이었으며, 우기시는 $195{\pm}11\;Bq/L,\;45.4{\mu}g/L$ 이었다.

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Radon Concentration in Groundwater of Korea (전국 규모로 본 국내 지하수의 라돈 함량)

  • Cho, Byong-Wook
    • The Journal of Engineering Geology
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    • v.28 no.4
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    • pp.661-672
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    • 2018
  • Radon concentration was measured in a total of 5,453 groundwater samples from wells across Korea. The radon concentrations showed the values ranging from 0.1 Bq/L to 7,218.7 Bq/L, with a median of 48.8 Bq/L which is lower than those of other countries having similar geological conditions. The distribution of radon concentrations was lognormal. The median value is high in the granite areas (63.5-105.1 Bq/L) while it is low in the sedimentary rocks and Cheju volcanic area (16.0-20.3 Bq/L). When grouping the groundwater with well depth, the median radon value is high in weathering and/or upper bedrock zone (61.4 Bq/L) while it is low in alluvium and/or weathering zone (28.5 Bq/L). About 17.7% of the total samples exceeded 148 Bq/L of USEPA guideline value. The exceeding radon ratio more than 148 Bq/L in groundwater is highest in Jurassic granite area, however, the exceeding radon rates more than 300 Bq/L and 500 Bq/L are highest in CGRA area.

The Study of Radon and Uranium Distribution in the Groundwater at Regional Difference of Daejeon (대전지역별 지하수중의 우라늄, 라돈 농도준위 분포조사 연구)

  • Yoon, Yoon-Yeol;Cho, Soo-Young;Lee, Kil-Yong;Kim, Yong-Je
    • Journal of Radiation Protection and Research
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    • v.31 no.1
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    • pp.25-30
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    • 2006
  • To know radon and uranium concentration variations in groundwater with regional difference, groundwaters were sampled at five different Daejeon area. Seventy-five samples were analyzed and forty samples were collected twice at drying and after raining season to know surface water effect. The average radon and uranium concentration of five areas are $270.9{\pm}152.3\;Bq/L,\;43.8{\pm}23.5\;{\mu}g/L$ at Yusung-gu, $112.9{\pm}65.8\;Bq/L,\;0.45{\pm}0.23\;{\mu}g/L$ at Seo-gu, $41.3{\pm}24.0\;Bq/L,\;4.9{\pm}11.3\;{\mu}g/L$ at Dong-gu, $131.8{\pm}99.5\;Bq/L,\;54.3{\pm}127.5\;{\mu}g/L$ at Daeduk-gu and $44.0{\pm}43.0\;Bq/L,\;8.1{\pm}11.6\;{\mu}g/L$ at Jung-gu. The mean concentrations of analyzed samples to know surface water effect were ranged from 0.5 to 640 ${\mu}g/L$ for uranium and from 0.4 to 729 Bq/L for radon. The average concentration of radon and uranium after raining season were lower than those of drying season. The mean contents of radon End Uranium at drying season were $253{\pm}14\;Bq/L,\;63{\pm}12.2\;{\mu}g/L$, and $195{\pm}11\;Bq/L,\;45.4{\pm}11.7\;{\mu}g/L$ after raining season.

Hydrogeochemical Characterization of Natural Radionuclides Uranium and Radon in Groundwater, Jeonnam Province (전라남도 일대 지하수 중에서 산출하는 자연방사성물질 우라늄과 라돈의 수리지구화학적 거동특징)

  • Cho, Byong Wook;Kim, Moon Su;Kim, Hyun Gu;Hwang, Jae Hong;Cho, Soo Young;Choo, Chang Oh
    • The Journal of Engineering Geology
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    • v.27 no.4
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    • pp.501-511
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    • 2017
  • Natural radionuclides such as uranium and radon from 170 groundwater wells in Jeonnam Province were investigated, together with hydrogeochemical properties, and concentration maps of uranium and radon were also constructed in this study. Characteristics of their concentrations and occurrence were discussed using hydrogeochemical factors and geostatistical methods based on individual geological units. Though uranium and radon in groundwater show a wide range in the concentration, most of which occur as low levels except a few sites. Based on factor analysis, correlation coefficients between uranium and radon are very low. Such results verify that these radionuclides behave independently, well consistent with most previous results investigated nationwide in groundwater. Besides uranium and radon, most hydrochemical components in groundwater show a close relation to indicate the water-rock interaction taken place actively in aquifer.