• 한국가스학회지
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• 제19권3호
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• pp.1-8
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• 2015

본 연구는 신발, 타이어, 접착제 제조에 많이 사용되는 클로로프렌(chloroprene)에 대해 취급근로자의 건강장해 예방을 위해 유해성을 조사하고, 취급사업장에 대해 작업환경을 측정 노출농도 및 용량반응을 통해 위험성을 평가하였다. 클로로프렌은 국제암연구소(IARC)로부터 발암추정물질(2B), 표적장기 전신독성 및 생식독성물질로 국내 취급 사업장은 27개소, 연간 약 1,300톤이 사용되었으며, 노출 위험성은 노출환경에 따라 Monte-carlo simulation을 이용하여 산출하였다. 그 결과 국소배기장치가 없으며 1일 4시간 초과 작업시 발암을 일으킬 수 있는 위험성의 평균값은 26,404로, 국소배기장치가 있으며 15분 미만의 단시간 작업 경우 2,199에 비교해 매우 높은 위험성을 보였다. 그리고 표적장기 전신독성의 경우도 169.06으로 단시간 작업 경우 4.10에 비교해 표적장기 전신독성 발생 위험이 높은 것으로 평가되어 물질의 노출시간 및 환기방식에 깊은 상관관계가 있는 것으로 나타났다. 따라서 클로로프렌 노출에 의한 근로자의 건강장해 예방하기 위해 국소배기장치의 가동과 방독마스크의 착용 등 노출저감을 위한 작업환경 관리의 필요성이 있었다. 특히 클로로프렌은 발암성, 생식독성 물질로 미국 산업안전보건청(OSHA)에서는 TWA를 5 ppm($18mg/m^3$) 이하로 관리하고 있으며, 본 유해성조사 결과에서도 현행 노출기준 10 ppm이하에서 표적장기독성, 생식기 장해 등 생체에 미치는 영향이 있는 것으로 나타나 있어, 위험성이 강하게 예측되므로 현재 사용하고 있는 우리나라 작업환경 노출기준(TWA 10 ppm)도 5 ppm 수준으로 강화하여 근로자 건강장해 예방에 기여할 필요성이 있는 것으로 판단되었다.

• 한국전산유체공학회지
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• 제10권4호통권31호
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• pp.66-71
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• 2005

HANARO, a multi-purpose research reactor, 30 MWth open-tank-in-pool type, is planning to produce a fission moly-99 of radio isotopes, a mother nuclide of Tc-99m, a medical isotope and a target handling tool is under development for loading and unloading it in a circular flow tube (OR-5) of HANARO. A guide tube is extended from the reactor core to the top of the reactor chimney for easily loading the target under a normal operation of the reactor. But active coolant through the core can be quickly raised up to the top of the chimney through the guide tube. The jet flow was suppressed in the guide tube after reducing the inner diameter of a flow restriction orifice installed in the OR-5 flow tube for adding the pressure difference in the flow tube. This paper describes an analytical analysis to calculate the flow distribution in the core of HANARO after suppressing the jet flow of the guide tube. As results, it was confirmed through the analysis results that the flow distribution in the core of HANARO were not adversely affected.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2005년도 춘계 학술대회논문집
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• pp.70-73
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• 2005

The HANARO, multi-purpose research reactor, 30 MWth open-tank-in-pool type, is planning to produce a fission moly-99 of radio isotopes, a mother nuclide of Tc-99m, a medical isotope and is under developing a target handling tool for loading and unloading it in a circular flow tube (OR-5). A guide tube is extended from the reactor core to the top of the reactor chimney for easily loading the target under the reactor normal operation. But active coolant through the core can be quickly raised up to the top of the chimney through the guide tube. The jet flow was suppressed in the guide tube after reducing the inner diameter of a flow restriction orifice installed in the OR-5 flow tube for adding the pressure difference in the flow tube after unloading the target. This paper describes an analytical analysis to calculate the flow distribution in the core of the HANARO after suppressing the jet flow of the guide tube. As results, it was confirmed through the analysis results that the flow distribution in the core of the HANARO were not adversely affected.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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• pp.502-507
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• 2003

The HANARO, multi-purpose research reactor, 30 MWth open-tank-in-pool type, is under normal operation since it reached the initial critical in February 1995. The HANARO is used for fuel performance tests, radio isotope productions, reactor material performance tests, silicone semiconductor productions and etc. Specially, the HANARO is planning to produce a fission moly-99 of radio isotopes, a mother nuclide of Tc-99m, a medical isotope and is under developing a target handling tool for loading and unloading those at a flow tube (OR-5). The target should be sufficiently cooled in the flow tube without an interference with the cooling of the others and an induction of extremely vibration. This topic is described an analectic analysis for the cooling characteristics of the fission moly-99 target to find the minimum cooling water. It was confirmed through the analysis results that the minimum cooling water, about 2.717 kg/s flew through the flow tube under the worst case that the guide tube got no perforating holes for cooling water to pass through the holes and that the target was safely cooled under about seventy percent (70%) of the maximum allowable temperature of the target.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2004년도 춘계 학술대회논문집
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• pp.208-213
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• 2004

The HANARO, multi-purpose research reactor, 30 MWth open-tank-in- pool type, is under normal operation since it reached the initial critical in February 1995. The HANARO is planning to produce a fission moly-99 of radio isotopes, a mother nuclide of Tc-99m, a medical isotope and is under developing a target handling tool for loading and unloading it in a circular flow tube (OR-5). A guide tube is extended from the reactor core to the top of the reactor chimney for easily un/loading a target under the reactor normal operation. But active coolant through the core can be quickly raised up to the top of the chimney through the guide tube by jet flow. This paper is described an analytical analysis to calculate the hole size of a orifice inserted in the circular irradiation hole and to study the flow characteristics through the guide tube under reactor normal operation and loading the target. As results, the results show that the hole size of orifice was 31 mm of the inner diameter to suppress the guide tube jet flow and the coolant safely cooled the target of fission moly after inserting the orifice to the flow tube.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2004년도 춘계 학술대회논문집
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• pp.214-219
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• 2004

The HANARO, a multi-purpose research reactor of 30 MWth, open-tank-in-pool type, has been under normal operation since its initial criticality in February, 1995. The HANARO is composed of inlet plenum, grid plate, core channel with flow tubes and chimney. The reactor core channel is located at about twelve m (12 m) depth of the reactor pool and cold by the upward flow that the coolant enters the lower inlet of the plenum, rises up through the grid plate and the core channel and exit through the outlet of chimney. A guide tube is extended from the reactor core to the top of the reactor chimney for easily un/loading a target under the reactor normal operation. But active coolant through the core can be Quickly raised up to the top of the chimney through the guide tube by jet flow. This paper is described an analytical analysis to study the flow behavior through the guide tube under reactor normal operation and unloading the target. As results, it was conformed through the analysis results that the flow rate, about fourteen kilogram per second (14 kg/s) suppressed the guide tube jet and met the design cooling flow rate in a circular flow tube, and that the fission moly target cooling flow rate met the minimum flow rate to cool the target.

• 한국전산유체공학회지
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• 제10권2호
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• pp.1-6
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• 2005

The HANARO, a multi-purpose research reactor of 30 MWth, open-tank-in-pool type, has been under normal operation since its initial criticality in February, 1995. The HANARO is composed af inlet plenum, grid plate, core channel with flow tubes and chimney. The reactor core channel is located at about twelve meters (12 m) depth of the reactor pool and cooled by the upward flow that the coolant enters the lower inlet of the plenum, rises up through the grid plate and the core channel and comes out from the outlet of chimney. A fission moly guide tube is extended from the reactor core to the top of the reactor chimney for easily loading a fission moly target under the reactor normal operation. But active coolant through the core can be quickly raised up to the top of the chimney through the guide tube by jet flow. This paper describes an analytical analysis that is the study of the flow behavior through the guide tube under reactor normal operation and unloading the target. As results, it was conformed through the analysis results that the flow rate, reduced to about fourteen kilogram per second (14 kg/s) from the original flow rate of sixteen point three kilogram per second (16.3 kg/s) did not show the guide tube jet.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1835-1840
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• 2004

The HANARO, a multi-purpose research reactor of 30 MWth, open-tank-in-pool type, has been under normal operation since its initial criticality in February, 1995. The HANARO is composed of inlet plenum, grid plate, core channel with flow tubes and chimney. The reactor core channel is located at about twelve meters (12 m) depth of the reactor pool and cooled by the upward flow that the coolant enters the lower inlet of the plenum,. rises up through the grid plate and the core channel and comes out from the outlet of chimney. A guide tube is extended from the reactor core to the top of the reactor chimney for easily un/loading a target under the reactor normal operation. But active coolant through the core can be quickly raised up to the top of the chimney through the guide tube by a jet flow. This paper describes an analytical analysis that is the study of the flow behavior through the guide tube under reactor normal operation and unloading the target. As results, it was conformed through the analysis results that the guide jet is suppressed under the top of the chimney after modifying the orifice diameter of 37.5 mm to 31 mm.

• 한국가스학회지
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• 제20권2호
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• pp.35-42
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• 2016

포름아미드(formamide)는 암모니아 냄새의 무색 액체로 흡입 시 자극성이 강하며, 급성독성 $LD_{50}$ 5,577 mg/kg(랫드), 표적장기(간장) 전신독성의 무유해영향농도(NOAEL)는 113 mg/kg/day) 및 생식독성물질(1B)로 작업환경 노출기준은 10 ppm이었다. 포름아마이드 취급사업장에 대한 작업환경 측정결과는 25개 시료 모두가 노출기준보다 매우 낮은 농도를 보였다. 그러나 작업강도, 국소배기장치의 가동 및 보호구(방독마스크)의 착용 여부 등 작업환경에 따라 노출농도가 변할 수 있어 가상 노출 시나리오별 노출량을 산출한 결과 노출량은 $5.16mg/m^3$, $1.72mg/m^3$, $0.43mg/m^3$으로 산출되었다. 이를 전신독성 및 생식독성의 유해성을 고려한 위험성을 평가한 결과 평균값은 0.02-0.58, 누적 90% 값은 0.02-0.66, 95% 값은 0.02-0.69로 모두 1보다 낮은 대체로 안전한 값으로 산출되었다. 단, 작업 상황에 따라 순간적 고농도에 노출될 위험도 있으며, 간독성 및 생식독성 물질이기에 건강장해 예방을 위해 노출되지 않도록 취급 시 주의가 요망된다.