• 한국환경보건학회지
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• 제48권4호
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• pp.236-243
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• 2022

Background: In the case of multiple exposures to different types of heavy metals, such as the conditions faced by residents living near a smelter, it would be preferable to group hazardous substances with similar characteristics rather than individually related substances and evaluate the effects of each group on the human body. Objectives: The purpose of this study is to evaluate the utility of factor analysis in the assessment of health effects caused by exposure to two or more hazardous substances with similar characteristics, such as in the case of residents living near a smelter. Methods: Heavy metal concentration data for 572 people living in the vicinity of the Janghang smelter area were grouped based on several subfactors according to their characteristics using factor analysis. Using these factor scores as an independent variable, multiple regression analysis was performed on health effect markers. Results: Through factor analysis, three subfactors were extracted. Factor 1 contained copper and zinc in serum and revealed a common characteristic of the enzyme co-factor in the human body. Factor 2 involved urinary cadmium and arsenic, which are harmful metals related to kidney damage. Factor 3 encompassed blood mercury and lead, which are classified as related to cardiovascular disease. As a result of multiple linear regression analysis, it was found that using the factor index derived through factor analysis as an independent variable is more advantageous in assessing the relevance to health effects than when analyzing the two heavy metals by including them in a single regression model. Conclusions: The results of this study suggest that regression analysis linked with factor analysis is a good alternative in that it can simultaneously identify the effects of heavy metals with similar properties while overcoming multicollinearity that may occur in environmental epidemiologic studies on exposure to various types of heavy metals.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.845-846
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• 2011

• 한국대기환경학회지
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• 제15권3호
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• pp.235-247
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• 1999

This study was performed to investigate what was the most serious occupational factors in small scale industries. Twenty-three occupatonally hazardous substances were measured at the five workplaces in the Eastern Seoul during 1995∼1996. Total of 2,020 samples were analyzed by either GC/FID for organic vapors or AAS for heavy metals. From the results of this study noise was the most serious factor at the selected workplaces. Noise level in the metal processing, the printing, and the auto repairing industries exceeded the 8 hr PEL by 19.7%, 13.6%, and 11.6%, respectively. Mean concentrations of toluene in the shoe making and the printing industries exceeded the assessment crieterion by 6.0% and 3.8%, respectively. Further study of risk assessment of occupational exposure may be required to protect workers from hazardous working conditons.

• 동아시아식생활학회지
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• 제21권3호
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• pp.401-417
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• 2011

The purpose of this study was to investigate consumer concerns about hazardous elements on foods and recognition of the roles of government, food producers, and consumers in securing food safety. The data were collected from the 443 adult consumers living in Seoul, Busan, Daegu, Incheon, Kwangju and Daejeon through a self-administered questionnaire. Frequencies, t tests, analysis of variance and Duncan's multiple range tests were conducted using SPSS Windows. The results of the survey were as follows: (1) the respondents were worried about health risks related to hazardous elements on foods, (2) many respondents were more worried about preservatives of imported foods than those of domestic foods, and (3) most respondents mentioned that observance of enforcement regulations by producers was the most important factor for ensuring food safety in the future. These results imply that regulations regarding the safety of imported foods should be increased.

• 한국방재학회 논문집
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• 제9권1호
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• pp.73-79
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• 2009

유해물질은 만일 누출된다면 화재 폭발 독성 및 위해성이 있는 물질을 말한다. 많은 선진국에서 유해물질의 수송이 증가하고 있기 때문에 유해물질의 생산 저장 수송 사용 및 폐기에 대한 정확한 정보는 매우 중요하다. 유해물질의 수송은 유해물질의 사용과정에서 핵심적인 기능이라고 말할 수 있다. 정부는 유해물질에 대해 많은 법령과 규제, 기준들을 개발해 왔다. 그러나 한국의 법령, 규제, 기준들은 비록 유해물질의 이동이 유해물질 수송에 대한 안전과 방재차원에서 중요한 정보임에도 불구하고, 유해물질의 O-D수송에 대한 정확한 정보를 보장하고 있지 못한 실정이다. 본 연구의 목적은 한국의 유해물질 수송에 대해 새롭게 대두되거나 기존에 제기된 이슈들을 조사하고, 제한된 자료를 가진 상황에서 유해물질에 대한 O-D매트릭스를 예측하는 기법을 개발하는 것이다. 본 연구는 유해물질 수송사례에 대한 40개의 후보군 중에서 수산화나트륨 폐기물에 대한 수송이 사례 연구로 선정하였다. 성장률법이 수산화나트륨 폐기물 수송의 2005년 O-D매트릭스를 추정하는데 적용되었다. 행렬보정기법이 추정된 수산화나트륨 O-D매트릭스를 보정하는데 사용되었다. 본 연구는 유해물질에 대한 O-D추정기법의 적용가능성을 제시하였다. 본 연구를 통해 도출된 수산화나트륨 폐기물 O-D 매트릭스는 수산화나트륨 수송의 수송로와 수송구간을 추적하는데 사용되어 진다.

• Journal of Preventive Medicine and Public Health
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• 제23권3호
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• pp.275-284
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• 1990

To obtain the useful information for the status of working environment and health management of workers in manufacturing industries, comparision of results on the status of working environmental and health management of workers for 32 manufacturing industries in Chunan area from 1988 to 1989 was carried out. The results were as follows : 1. The rate of over-PEL (Permissible Exposure Limit) to for hazardous factors decreased significantly 23.5% in 1988, 18.3% in 1989 (p<0.05) and, the highest rate of over-PEL was the stone and sand handling industry, the highest rate of over-PEL was the dusty workplace as 38.5% in 1988, 35.2% in 1989. 2. The rate of workers exposed to hazardous factors in 1988 and in 1989 was 22.4% respectively, the rate of workers checked up special health examination was 40.1% in 1988, 75.3% in 1989. In stone and sand handling and medicochemical industries, none of workers exposed to hazardous factors was subjected to special health examination in 1988, but 75% of workers exposed to hazardous factors had checked up in 1989. 3. The 6 industries appointed as part-time factory physician among 17 industries which were supposed to have factory physician according to the Safety and Healthy Act of Korea, 6 out of 24 industries only appointed industrial hygienist, furthermore 4 out of 6 hygienists had another duty in addition to occupational hygiene itself.

• 한국가스학회지
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• 제6권1호
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• pp.81-85
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• 2002

탱크와 연결된 배관에서 원하지 않은 사고로 인해 액체 위험물질의 누출이 발생할 경우 천이영역에서의 누출속도 계산방법을 제시하였다. 배관에서의 액누출에 관한 누출속도는 층류와 난류영역에서 Crowl and Louvar 등이 제시한 모델식을 이용하여 프로그램 또는 직접계산에 의해 이루어지고 있으나, 천이영역에 대한 모델식은 없었다. 따라서 본 논문에서는 Lap-Mou Tam 등이 실험한 천이영역에서 레이놀즈수에 따른 마찰계수 실험값을 이용하여 천이영역에 대한 누출속도 값을 계산하였고 이 값을 층류와 난류에 관한 모델식을 사용한 값과의 비교를 통해 천이영역에서 일반적으로 사용할 수 있는 모델식으로 난류에 관한 모델식으로 계산한 값에 안전율 $30\%$를 추가한 값을 위험평가에 사용할 수 있음을 보였다.

• 한국환경과학회지
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• 제13권7호
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• pp.703-710
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• 2004

Petroleum refineries have been considered as an important emission source for atmospheric volatile hazardous air pollutants(HAPs). The emission source includes petroleum refinery processes and process equipment. The control strategy for volatile HAPs requires emission estimations of these pollutants. However, systematic methods of volatile HAPs emission from petroleum refineries have not yet been established. Accordingly, present study surveyed the estimation method of volatile HAPs emitted from the petroleum refinery processes and process equipment. The emission estimation methods for the petroleum refinery processes are applied for 11 petroleum refining facilities: fluidized catalytic cracking, thermal cracking, moving bed catalytic cracking, compressed engine, blowdown system, vacuum distilled column condensator, natural gas or distilled boiler, natural gas or distilled heater, oil boiler, oil heater and flare. Four emission estimation methods applied for the petroleum refinery process equipment are as follows: average emission factor approach, screening ranges approach, EPA correlation approach and unit-specific correlation approach. The process equipment for which emission factors are available are valves, pump seals, connectors, flanges and open-ended lines.

• 보건교육건강증진학회지
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• 제22권4호
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• pp.203-213
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• 2005

Purpose: To assess the environmental hazards of falling accident in the homes of the elderly. Method: 222 homes of the elderly were assessed by the home environmental Checklist from May to July in 2003. Results: The mean score of home environmental hazards for fall were 13.19 with the highest score being 49, ranging from 4 to 24. The bathroom was the most hazardous place in the home, porch came next bedroom, kitchen, living room and stair followed them. The floor surface such as finishes and non-skid mats was the most hazardous interior factor in the home, using bathroom came next furniture and illumination followed them. The floor surface such as finishes and non-skid mats in the bathroom, kitchen, living room and porch, illumination of bedroom and stair were the most prevalent hazards in the home of interior. Of the 49 potential hazards, bathroom grab bar was the most prevalent one with 89.9%, and non-skid rugs in the porch, bathroom and kitchen, safety of dinner table, the threshold and furniture of porch, and illumination of bedroom were prevalent more than half of the home under assessing. Men, living in the separate house or villa with stairs were in more hazardous environments. Conclusion: To reduce the potential hazards of fall accident in the home, improving hazards relating to floor surface such as slip resistance surface and mats is important specially those of the separate house or villa with stairs.

• 한국안전학회지
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• 제33권4호
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• pp.21-29
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• 2018

In many companies handling flammable liquids, explosion-proof electrical equipment have been installed according to the Korean Industrial Standards (KS C IEC 60079-10-1). In these standards, hazardous area for explosive gas atmospheres has to be classified by the evaluation of the evaporation rate of flammable liquid leakage. The evaporation rate is an important factor to determine the zones classification and hazardous area distance. However, there is no systematic method or rule for the estimation of evaporation rate in these standards and the first principle equations of a evaporation rate are very difficult. Thus, it is really hard for industrial workplaces to employ these equations. Thus, this problem can trigger inaccurate results for evaluating evaporation range. In this study, empirical models for estimating an evaporation rate of flammable liquid have been developed to tackle this problem. Throughout the sensitivity analysis of the first principle equations, it can be found that main factors for the evaporation rate are wind speed and temperature and empirical models have to be nonlinear. Polynomial regression is employed to build empirical models. Methanol, benzene, para-xylene and toluene are selected as case studies to verify the accuracy of empirical models.