• Title/Summary/Keyword: 공기중 농도

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노출평가를 위한 TLV 근거 - PHOSPHORUS TRICHLORIDE (삼염화인)

  • Kim, Chi-Nyeon
    • 월간산업보건
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    • s.385
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    • pp.9-13
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    • 2020
  • 삼염화인(Phosphorus trichloride)의 노출기준은 눈, 피부, 점막 그리고 호흡기계 기관지 자극의 가능성을 최소화하기 위해 TLV-TWA는 0.2ppm(1.1 mg/㎥), TLV-STEL은 0.5ppm(2.8 mg/㎥)으로 권고하였다. 삼염화인은 직접 피부 접촉 시 심각한 화상을 유발할 수 있으며 공기 중 농도 2ppm~27ppm 범위에서 작업자가 급성 노출되면 인두, 기침, 호흡 곤란 및 심한 천식 기관지염을 유발하는 것으로 보고되었다. 물 또는 습한 공기에서 삼염화인은 염산 및 인산으로 분해된다.(ACGIH의 인산 TLV 문서를 참조하는 것이 필요함). 피부흡수(Skin), 감작제(SEN)의 경고주석과 발암성을 표기하기에는 유용한 자료가 충분하지 않다.

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오존의 살균 및 탈취와 오존발생기의 발생농도 변화

  • Yun, Yeong-Mi;Go, Myeong-Seok;Kim, Hyeon-Jong;Lee, Eun-Mi;Jeong, Bong-U;Lee, Hyeon-Cheol
    • 한국생물공학회:학술대회논문집
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    • 2000.11a
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    • pp.473-474
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    • 2000
  • Ozone has a potency for disinfection, deodorization, decolorization and decomposition of organic materials by strong oxidation. therefore we used the ozonizer to disinfection and deoderization of a piggery. CFU of the ozonated piggery was lower than the others. And the of ozonizer was redesigned from open-type to close-type to obtain high ozone concentration. We was also investigated the effect of air velocity to ozone concentration.

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Application of Ultrasound for the Decomposition of Musty-Odorous Compounds in Water (수용액 중 Musty-Odorous Compound류의 분해에 따른 초음파의 응용)

  • 유영억;영전양웅;전전태소
    • Journal of environmental and Sanitary engineering
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    • v.13 no.1
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    • pp.1-8
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    • 1998
  • Musty-odorous compound (Geosmin, 2-Methylisobrneol) 수용액 중에 초음파 (200kHz, $6.0W/cm^{2}$)를 조사시켜 조사시간에 따른 농도 및 취기의 변화를 고찰했다. 초음파 조사에 의해 이 물질들은 빠르게 분해되었고 분해 형태는 농도에 대한 유사1차 반응을 나타내었다. 공기 포화 분위기에서 이들의 초기 분해속도는 각각 2.5 $10^{-3}{\;}Msec^{-1}$(2-MIB), 3.2 $10^{-3}{\;}Msec^{-1}$ (Geosmin)로 나타났다. 초음파 조사 시 포화가스 (Envelope gas)의 영향은 아르곤(Ar) 산소($O_{2}$) 공기(Air) 질소($N_{2}$) 순서로 순수한 아르곤(Ar) 분위기에서 musty-odorous compound 류의 분해가 가장 빠르게 진행되었고 그 분해생성물로 CO, $CO_{2}$ 그리고 HCOOH, $CH_{3}COOH$ 등의 저급 유기산류가 검출되었다. 또한 이들의 분해반응은 물의 초음파분해에 따라 생성된 hydroxylradical에 의한 radical반응, cavitation bubble내에서의 고온고압에 의한 열분해 및 직접연소반응으로 진행됨을 알 수 있었다.

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A basic study for thermal performance improvement of domestic oil boiler (家庭용 油類 보일러의 熱性能 向上에 관한 基礎設計 硏究)

  • 정진도;이은모;류정인
    • Journal of Energy Engineering
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    • v.4 no.1
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    • pp.31-41
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    • 1995
  • 본 연구에서는 일반 가정에서 많이 쓰이고 있는 15,000 Kcal/hr용량의 유류 보일러에 대한 제반 실험을 통하여 보일러 운전자료를 제공함은 물론 방열코일의 열교환 실험을 통하여 시중에 유통되고 있는 방열코일의 방열량 비교와 공기와 냉각수와의 열관류율을 비교함으로서 보일러 시공에 필요한 기초 자료를 얻었다. 연소에 필요한 급기량은 매연농도가 문제시 되지 않는 Smoke Scale No.가 1 이하인 공기비 1.45 이상으로 운전이 되어야 하며 송수온도는 t2=-0.0781XGw+85($^{\circ}C$)의 실험식으로 표시할 수 있다. 공기중에서 코일의 방열량은 X-L관이 외경의 차이로 인해 동관보다 높게 나타났다.

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Volatilization of molinate in paddy rice ecosystem and its concentration in air causing phytotoxicity to chili pepper (벼 재배 환경 중 molinate의 휘산과 공기 중 고추약해 발현농도)

  • Park, Byung-Jun;Choi, Ju-Hyeon;Kim, Chan-Sub;Im, Geon-Jae;Oh, Byung-Youl;Shim, Jae-Han
    • The Korean Journal of Pesticide Science
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    • v.9 no.1
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    • pp.70-80
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    • 2005
  • To evaluate the exposure of molinate in agricultural environment and its effect against the non-target crop in air, this experiment was conducted to elucidate volatilization characteristics of molinate in aquatic condition and to determine critical concentration of molinate in the air causing phytotoxicity to Chili pepper. Cumulative volatilized rate of molinate from water was 22.7% at $35^{\circ}C$ for water temperature and 20 L/min for air velocity while 3.2% at $25^{\circ}C$ and 10 L/min within 47 hour after applied under closed system, respectively. The molinate concentrations in air above 60 cm height from soil surface of valley and open paddy rice field were reached the highest value of 18.17 and $11.59{\mu}g/m^3$, respectively within 24 hours after applying granular formulation at dose rate of molinate 150 g/1,000 $m^2$. However, their concentrations were drastically diminished to around 0.18 and $0.51{\mu}g/m^3$ level in 20 days after application, which volatilization pattern were similar to both regions. Also, the concentration of molinate in air above 60 cm height from soil surface was distributed higher 2 times than that above 180 cm height. Meanwhile, a phytotoxic symptom against the nearby chili pepper was revealed within three days after applied and molinate was detected $0.004{\sim}0.006$ mg/kg level from severe damaged leaves. The dose and exposure relations of molinate in the air against the non-target crop was also investigated in lab trial. The phytotoxic symptom, shriveled leaves, of the chili pepper was encountered by exposing two days with concentration of $13.6{\mu}g/m^3$, three days with $6.8{\mu}g/m^3$ or four days with $3.4{\mu}g/m^3$. The symptom was still recovered within four weeks after the plants had received fresh air. On the other hand, the phytotoxic response through root uptake of the herbicide in water culture was relatively insensitive, in which the symptom is observed ten days with the concentration of 300 ${\mu}g/L$.

Radon Concentration at N-Kindergarten in G-City (G광역시 N유치원의 라돈 농도)

  • Park, Yun;Kim, Wonjun
    • Journal of the Korean Society of Radiology
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    • v.9 no.6
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    • pp.421-424
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    • 2015
  • In this study, To subject the constructed at N-kindergarten in G-city, the position is closed window and opened window was measured using a measuring instrument for radon. The measured results indicate that the measurement was carried out in concentrations of radon gas measured at N-kindergarten is low than United States in the radon concentration in air public 4pCi called radon gas baseline maximum allowable concentrations. As a result, radon exposure is not a problem, but when the accumulation radon gas in the lungs, get damaged same lung cancer. Be defensive of kindergarten windows open for ventilation and dust removal be possible to reduce the exposure.

초등학교 6학년 염산 사용 실험의 실내공기 오염 연구

  • Jeong, Han-Yeong;Mun, Yun-Seop
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2006.11a
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    • pp.510-512
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    • 2006
  • 초등학교 염산관련 실험 시 발생하는 염화수소의 실내공기 중의 농도가 이산화탄소 발생 실험의 경우 8.93ppm, 수소 발생 실험의 경우 4.46ppm이 발생한다. 이 수치는 코에 자극 주고 불쾌감을 동반하거나, 코에 자극이 강하며 30분 이상 견딜 수 없는 수치에 근접하는 결과이다.

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Survey on the Concentration of Sulphur Dioxide Gas in the Plastic Film House Cultivation (시설(施設) 하우스내 아황산(亞黃酸)(SO2)가스 발생현황(發生現況) 조사(調査))

  • Kim, Bok-Young;Lee, Jong-Sik;Jung, Goo-Bok
    • Korean Journal of Soil Science and Fertilizer
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    • v.30 no.4
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    • pp.357-360
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    • 1997
  • To fine out the concentration of $SO_2$ gas in plastic film house, the survey was conducted at 343 sites throughout the nation. The $SO_2$ concentration in plastic film house were similar both heating and non-heating, but $SO_2$ cocentration higher than 0.8ppm was detected at those with heating. The $SO_2$ concentration in plastic film house cultivated red-pepper higher than those of cucumber or tomato cultivation, and it was produced higher amounts at day time than night due to the higher temperature. In plastic film house with heating, $SO_2$ was leaked at brocken parts of heater and joint of stove pipe, sometimes, $SO_2$ discharged from smokestack was resucked with air. $SO_2$ concentration in the plastic film house with and without ventilation were 0.2 and 0.6ppm, respectively.

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On-Line Measurement of Solid Particles in Air Using a Quartz Crystal Microbalance (수정진동자 미량저울을 이용한 공기 중 먼지의 온라인 측정)

  • Choi, Kwang-Jae;Kim, Young-Han;Chang, Sang-Mok
    • Journal of Sensor Science and Technology
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    • v.8 no.4
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    • pp.314-319
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    • 1999
  • The measurement of solid particles suspended in air is conducted with a quartz crystal microbalance. The measurement system is connected to a personal computer and multiple sensors are utilized to make simultaneous measurement possible. In this paper, the detail of experimental setup is extensively explained for the possible future application of the system in other areas. It is found that the measurement system is suitable for an on-line continuous determination of the concentration of solid particles in air.

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Characteristics of Indoor PM2.5 and the effect of air purifier and ventilation system on Indoor PM2.5 in the Knowledge Industrial Center office during the atmospheric PM2.5 warning (초미세먼지 주의보 시 지식산업센터 사무실의 실내 초미세먼지 농도 특성과 공기청정기와 환기장치의 영향)

  • Ji, Jun-Ho;Joo, Sang-Woo
    • Particle and aerosol research
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    • v.16 no.3
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    • pp.65-72
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    • 2020
  • In this study, the indoor fine dust concentration in an office of the Korea Knowledge Industry Center was measured for about 80 hours when the concentration of atmospheric PM2.5 was very high. The effect of the operation of the air cleaner and the forced ventilation system on the indoor PM2.5 was investigated, and the particle size distribution of the indoor and outdoor particles was analyzed. When forced ventilator and air purifiers were partially used, the indoor PM2.5 concentrations were maintained between 27.7 ㎍/㎥ and 32.9 ㎍/㎥ when the atmospheric PM2.5 was 127.7 ㎍/㎥ to 141.6 ㎍/㎥ during working hours. It is more effective to operate the air purifier without operating the forced ventilation system when the concentration of the PM2.5 is high since the PM2.5 penetrating the installed filter is continuously introduced indoor from the outside.