플럭스 코어드 아크 용접 공정에서의 흄 형성량에 관한 연구

윤충식,백남원,Yoon, Chung-Sik,Paik, Nam-Won 한국환경보건학회 1999 한국환경보건학회지 Vol.25 No.3

A study was conducted for the effects of input energy on fume formation ratios based on electrode(FFR$_{electrode}(g/kg_{electrode})),\;deposited\;metal(FFR_{weld}(g/kg_{weld}))\;and\;slag(FFR_{slag}(g/kg_{slag}))\;at\;CO_2$ flux cored arc welding on stainless steel. Experiments were run in well designed welding fume box. Six types of flux cored wires were used and three levels of current and voltages were given. The measured values of $FFR_{electrode},\;FFR_{weld},\;FFR_{slag}\;are\;7.90{\pm}1.47\;g/kg_{electrode},\;9.18{\pm}1.65\;g/kg_{\electrode},\;71.8{\pm}24.2\;g/kg_{slag}$ respectively. Fume formation ratios are not increased dramatically by input energy because of simultaneous increasing of melted electrodes, deposited metal and slag. The results indicate that the test of fume formation ratios in the research on production of low fume welding wire can be run at the fixed condition of input energy rather than various condition.

환경부의 화학물질관리법, 화학물질등록 및 평가에 관한 법률, 고용노동부의 산업안전보건법의 화학물질 관련 내용 비교

윤충식,함승헌,박지훈,김선주,이상아,이권섭,박동욱,Yoon, Chungsik,Ham, Seunghon,Park, Jihoon,Kim, Sunju,Lee, Sangah,Lee, Kwonseob,Park, Donguk 한국환경보건학회 2014 한국환경보건학회지 Vol.40 No.5

Objectives: The exponential growth of chemicals, an area of high concern in developed countries like the US (i.e., the Gore Initiative) and in the EU (i.e., REACH), as well as recent chemical accidents in Korea, have provoked nationwide concerns and resultant legal enforcement. This study aims to compare the laws of the Ministry of Environment (the Chemical Substances Control Act (CSCA), Act on the Registration and Evaluation, etc. of Chemical Substances (ARECS)) with those of the Ministry of the Employment and Labor (Occupational Safety and Health Act (OSHA)). Methods: Each law pertaining to the Ministry of Environment and the Ministry of the Employment and Labor was downloaded from the official legal information system (www.law.go.kr). The objectives of each law and the major contents related to chemical management were compared and summarized. Results: The CSCA and the ARECS are focused on the protection of people and the environment, while the OSHA relates to the protection of workers. The right to know of people and workers has been reinforced. The former two laws emphasize prevention, but the OSHA contains both preventive and post-accident measures. The role of the Ministry of Employment was reinforced with the promulgation of the CSCA and ARECS, which contain regulations such as adjacent area impact evaluation, risk control planning, chemical statistical survey and construction and operation of information, provision of risk control plans, response to chemical accidents and registration of chemical substances. Conclusion: We found that the three laws discussed here have several similar clauses designed to protect people and the environment from risks that may be caused by the use of chemicals, even though there are some differences among them in terms of objectives and contents. This review concluded that several clauses that can be regarded as double regulation should be unified in order to minimize the waste of government administrative resources and socio-economic losses.

나노물질의 측정전략의 주요 쟁점

윤충식,Yoon, Chung-Sik 한국환경보건학회 2011 한국환경보건학회지 Vol.37 No.1

The growing interest in nanotechnology has resulted in increasing concern and a number of published environmental and workplace measurements for assessing occupational exposure to engineered nanomaterials. However, the amount of previous exposure data remains limited. Furthermore the data available was collected with extensive variation in terms of exposure measurement strategy, which limits the ability to pool the data in the future. In response, this paper reviewed several pertinent issues related to exposure measurement strategy to suggest a harmonized measurement strategy which would make exposure data more useful in the future, e.g. correlation between exposure metrics, relationship between activity and exposure, task-based or shift-based assessment, background concentration, limitation of personal exposure monitoring and other determinants of exposure/modeling. An improved sampling strategy for nanomaterial exposure assessment should be considered in order to maximize the use of the data from various real time monitoring instruments.

유아교육시설의 표면 및 공기 중 납 농도 평가

윤충식,백도현,Yoon, Chung-Sik,Paik, Do-Hyeon 한국환경보건학회 2006 한국환경보건학회지 Vol.32 No.1

This study was performed to investigate airborne lead concentration and surface lead contents in preschool facilities. Arithmetic mean of indoor lead concentration in urban area was $44.7\;ng/m^3$ (Geometric mean $32.1\;ng/m^3$) whereas outdoor concentration was $39.5\;ng/m^3$ (GM $22.8\;ng/m^3$). In rural area, airborne lead concentrations were $14.2\;ng/m^3\;(GM\;7.9 ng/m^3),\;12.6\;ng/m^3\;(GM\;5.6 ng/m^3)$, respectively. There is statistical significance of the lead concentrations among the locations of preschool facilities. About $37\%$ of qualitative lead check samples was positive and mainly was found in lead based paint. Though lead concentrations on the floor and window sill were well below the US EPA and HUD standard (floor $40\;{\mu}g/ft^2\;(4.3\;{\mu}g/100\;cm^2)$, window sill $250\;{\mu}g/ft^2\;(26.9\;{\mu}g/100\;cm^2)$, respectively), there were much samples which exceed the standard, i.e., $29\%$ of surface wall, $20\%$ of the desk and chair, $100\%$ of painted wood box of tested samples. In view of our study and hazard of lead to children, we recommended that the contents of lead in preschool facilities should be lowered as possible.

유아교육시설의 위치 및 실내${\cdot}$실외에 따른 포름알데히드 농도 변화

윤충식,정지연,이광용,박동욱,박두용,Yoon , Chung-Sik,Jeong , Jee-Yeon,Yi , Gwang-Yong,Park , Dong-Uk,Park , Doo-Yong 한국환경보건학회 2004 한국환경보건학회지 Vol.30 No.3

This study was performed to investigate airborne formaldehyde concentration in preschool facilities. Arithmetic mean of indoor formaldehyde concentration in urban area was 34.9 ppb(Geometric mean 24.4 ppb) whereas outdoor concentration was 21.5 ppb(GM 11.9 ppb). In rural area, formaldehyde concentrations were 36.4 ppb(GM 28.7 ppb), 4.1 ppb(GM 4.1 ppb), respectively. There is no statistical significance between the formaldehyde concentrations of urban classrooms and those of rural area. We verified that the distribution of airborne formaldehyde concentration was log-normal characteristic using Shapiro and Wilk test. The 6.7% of urban indoor samples was exceeded the domestic standard limit of indoor air quality. From our study and other study, we concluded that the major emission sources of formaldehyde in preschool facilities was in indoor rather than outdoor.

석면과 건강에 대한 이슈

윤충식,Yoon, Chung-Sik 한국환경보건학회 2009 한국환경보건학회지 Vol.35 No.5

Asbestos is a commercial term of natural occurring silicated minerals and forms long, thin fibers. Chrysotile, the serpentine asbestos, accounts for most use in commercial use. Asbestos is well known health hazard material and it is proved that inhalation of asbestos fibers leads to increased risk of developing several diseases such as lung cancer, mesothelioma, asbestosis. In these days, people most at risk for exposure are maintenance and construction workers and general citizens who are working on and close to the work area at which asbestos containing material is disturbing. Non asbestiform, though its chemical composition is same with regulated asbestos, is known to be less hazardous than asbestiform. Exposure guideline, 0.01 f/ml, is not safe level in terms of health risk. It is reasonable to take preventable action when asbestos is suspicious. In Korea, it is necessary to clarify the concept between hazard and risk, to differentiate asbestiform from non asbestiform, to make regulations for compensation for asbestos related patients, to manage future exposure for general citizens.

스테인레스 강 용접중 발생하는 망간의 발생량 및 함량변화에 관한 연구

윤충식 ( Chung Sik Yoon ),김정한 ( Jeong Han Kim ) 한국산업위생학회 2006 한국산업보건학회지 Vol.16 No.3

Manganese has a role as both toxic and essential in humans. Manganese is also an essential component in the welding because it increases the hardness and strength, prevents steel from cracking of welding part and acts as a deoxidizing agent to form a stable weld. In this study, manganese generation rate and its content was determined in flux cored arc welding on stainless steel. Domestic two products and foreign four products of flux cored wires were tested in the well designed fume generation chamber as a function of input power. Welding fume was measured by gravimetric method and metal manganese was determined by inductively coupled plasma-atomic emission spectrophotometer. The outer shell of the flux cored wire tube and inner flux were analyzed by scanning electron microscopy to determine their metal compositions. Manganese generation rate(FGRmn) was increased as the input power increased. It was 16.3 ㎎/min at the low input power, 38.1 ㎎/min at the optimal input power, and up to 55.4 ㎎/min at the high input power. This means that FGRmn is increased at the work place if welder raise the current and/or voltage for the high productivity. The slope coefficient of FGRmn was smaller than that of the generation rate of total fume(FGR). Also, the correlation coefficient of FGRmn was 0.65 whereas that of FGR is 0.91. FGRmn was equal or higher in the domestic products than that of the foreign products although FGR was similar. From the electron microscopic analytical data, we concluded that outer shell of the wire was composed mainly of iron, chromium, nickel and less than 1.2 % of manganese. There are many metal ingredients such as iron, silica, manganese, zirconium, titanium, nickel, potassium, and aluminum in the inner flux but they were not homogeneous. It was found that both FGRmn and content of manganese was higher and more varied in domestic flux cored wires than those of foreign products. To reduce worker exposure to fumes and hazardous component at the source, further research is needed to develop new welding filler materials that improve the quality of flux cored wire in respect to these points. Welder should keep in mind that the FGR, FGRmn and probably the generation rate of other hazardous metals were increased as the input power increase for the high productivity.

[산업보건] 초음파 전처리에 의한 용접 흄 중 6가 크롬의 분석

윤충식(Chung-Sik Yoon),백남원(Nam-Won Paik),김정한(Jeong-Han Kim),박동욱(Dong-Uk Park),최상준(Sang-Jun Choi),김신범(Shin-Bum Kim),채현병(Hyun-Byung Chae) 한국분석과학회 1999 분석과학 Vol.12 No.5

스테인레스 강에 대한 플럭스 코어드 아크 용접공정에서의 흄 발생량 및 입자 크기 분포에 관한 연구

윤충식(Chung Sik Yoon),백남원(Nam Won Paik) 한국환경보건학회 1999 한국환경보건학회지 Vol.25 No.2

A study was conducted for the effects of currents and voltages on the fume generation rates at CO₂ flux cored arc welding on stainless steel. Fume size distributions were also studied. Experiments were run in well designed welding fume box. Six types of flux cored wires were used and three levels of currents and voltages were given. Fume generation rates of domestic flux cored wires are 0.2-0.3 g/min at the lowest input energy and 0.81~0.85 g/min at the highest input energy tested. Fume generation rates could be related to the welding current with secondary power function and to the input energy with primary power function. Flux cored wires, when melted by arc, transfered into the deposited metal(82 ~92% ), slag(9~13% ), spatter(l~6% ), and fume(0.5~1 % ) respectively. Fulx cored welding fumes are all respirable particulate mass.

전자현미경을 이용한 미세 플라스틱 및 마이크로 파티클 분석 방법

윤충식 ( Choong-sik Yoon ),고용규 ( Yong-kyu Ko ),김용주 ( Yong-ju Kim ),홍지우 ( Ji-woo Hong ),장병현 ( Byung-hyun Jang ),정준영 ( Jun-yeong Jung ),이준희 ( Junhee Lee ) 한국폐기물자원순환학회(구 한국폐기물학회) 2020 한국폐기물자원순환학회 춘계학술발표논문집 Vol.2020 No.-

1960년대 이후 전 세계적으로 플라스틱의 사용량이 증가하며 국내에서도 2014년 기준 약 15백만톤의 플라스틱을 생산, 사용하고 있다. 이러한 플라스틱은 재활용으로 사용되기도 하지만 무단으로 버려지는 플라스틱 또한 기하급수적으로 늘어나며, 자외선, 파도 및 바람에 풍화되어 마모되거나 파쇄 되어 토양과 담수, 해수에 미세 플라스틱으로서(Microplastic) 존재하게 된다. 이러한 미세개재물들을 통들어 마이크로파티클(Microparticle)이라고 하며, 큰 개재물보다 미세 단위로의 개재물들은 환경오염과 인류의 건강에 훨씬 더 큰 영향을 끼칠 수 있기 때문에 개재물들의 형태와 성분 분류에 관심이 더 집중되고 있다. 해당 파티클의 성분을 알기 위해 푸리에 변환 적외선 분광학(Fourier-Transform Infrared Spectroscopy, FT-IR)을 통해 2차, 3차의 분석으로 미세 파티클에 대한 분석 기술을 널리 사용해왔다. 이 분석 방법은 밀리미터(mm)에서 수백 마이크로미터(um) 크기의 파티클에 대한 분석 기술에 사용하고 있지만, 수십 마이크로 미터에서 서브 마이크로 미터 수준의 미세, 초미세파티클에 대한 분석 기술에는 물리적인 한계로 사용될 수 없으며, 새로운 분석 기술이 마련되어야 한다. 전자현미경(SEM)을 통하여 미세 파티클 분석기술인 ISO 규격으로 45mm 멤브레인 필터를 사용하여 미세파티클 시료를 채취하고, 시료가 채취된 필터를 전자현미경을 통해 전체 면적에 대해 파티클의 크기, 개수를 분류하고, 해당 파티클 마다 X-ray를 검출함으로써 동시에 각 파티클의 성분도 분류할 수 있다. 이를 통해 멤브레인 필터전체 면적에 대한 파티클의 개수, 크기, 성분을 체계화 하여 분류 할 수 있다. 따라서, 본 연구에서는 눈으로 보이지 않는 미세플라스틱 및 파티클을 채취하여 전자현미경을 통해 화합물들을 정성·정량, 크기와 개수 및 분포를 얼마나 효과적으로 분석하고, 분류할 수 있는지에 대한 분석 기술을 알아보고자 하였다.