• 한국입자에어로졸학회지
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• 제17권1호
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• pp.1-8
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• 2021

The purpose of this study is to assess respirable crystalline silica (RCS) exposure levels in workers who collect and dispose used coal briquette ash (CBA) in sanitation companies that are subcontracted by one medium-sized local government on the collection of municipal household waste (MHW), and to analyze the quartz content in CBA. When the CBA powder that undergone specialized pretreatment in several steps were subjected to mineral identification and quantitative analysis using X-ray diffraction (XRD), it was found that quartz represented 18%, and in addition, mullite, and plagioclase were included. For two CBA collectors, samples were collected by the personal sampling evaluation method. After respirable dust was collected in accordance with the National Institute for Occupational Safety and Health 7500 method, the concentration of quartz was analyzed using XRD. Meanwhile, a portable real-time dust monitor (Sidepak AM520, TSI Inc., USA) was also used to observe the dust exposure level for each time zone and job task. The RCS exposure level of one worker was as high as 0.024 mg/㎥, which was the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values (TLV) level. The other worker also exhibited a concentration of 0.013 mg/㎥, which was more than half of TLV. The Sidepak results revealed that the work of collecting CBA and loading it onto a vehicle was hardly exposed to the dust of a significant level. It was found, however, that the work of transferring the collected CBA to a container through a conveyor belt was exposed to a very high average respirable dust concentration of 2.238 mg/㎥. The results of this study confirmed that quartz, which is crystalline silica and a carcinogen, is contained in CBA, one of municipal household waste (MHW), in high concentration. It was also confirmed that workers are exposed to high RCS concentrations while transferring collected CBA into a container. Although each local government in South Korea handles CBA in different ways, it is imperative to investigate the CBA exposure level of sanitation workers and improve their working conditions.

• 한국산업보건학회지
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• 제33권3호
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• pp.308-316
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• 2023

Objectives: The aim of this study is to measure and assess the occupational noise exposure levels among construction workers at apartment building construction sites in South Korea. Methods: Noise exposure assessments were conducted for 139 construction workers across 10 different trades at 53 apartment building construction sites in the northern part of Gyeonggi-do. Assessments were carried out using a noise dosimeter set with a 90 dB criterion, an 80 dB threshold, and a 5 dB exchange rate over a period of more than 6 hours(L_MOEL) Results: The mean L_MOEL (equivalent continuous noise level over 8 hours) for the 139 dosimeter samples was 87.8 ± 4.3 dBA. The mean noise exposure level for each construction trade, referred to as the trade mean, was also calculated. Significant differences in noise exposure levels were observed between construction trades (ANOVA, p < 0.001). The highest L_MOEL values were recorded for concrete chippers (93.2 ± 2.6 dBA), followed by ironworkers (88.4 ± 0.7 dBA), concrete finishers (88.3 ± 2.7 dBA), masonry workers (87.7 ± 1.9 dBA), pile driver operators (85.6 ± 1.7 dBA), concrete carpenters (84.9 ± 2.4 dBA), interior carpenters (83.5 ± 2.1 dBA), and other groups (81.4 ± 2.2 dBA). Conclusions: The findings suggest that nearly all construction workers in this study are at risk of Noise-Induced Hearing Loss (NIHL). Moreover, the study establishes that construction trades can serve as a useful metric for assessing noise exposure levels at apartment construction sites.

• 한국철학논집
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• 제43호
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• pp.171-202
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• 2014

본 연구는 해방 이후 현대 교육의 이상적 인간상을 살펴보기 위하여 우선 해방 이후에서 90년대에 이르는 시기를 광복 이후 분단까지의 '전환기'와, 경제성장을 통한 현대 국가 발전의 기반이 된 '산업화 시기', 그리고 다양한 계층의 사람들이 정치?경제?사회 참여를 요구하는 '민주화 시기'의 세 시기로 구분하고, 각 시기의 특성에 대해 정치 경제 사회 문화 등 다양한 측면에서의 접근을 시도하였다. 특히, 교육적 인간상의 추출을 위하여 이들 각 시기의 주요 가치를 탐색함으로써 이와 관련한 각 시기별 인간상을 고찰하였다. 시기별로 나타나는 주요가치와 인재상은 다음과 같다. 전환기의 주요가치로는 예의와 규범을 제시할 수 있으며, 추구하는 인재상은 무실역행(務實力行)하는 자세가 강조되는 실천적 지식이었다. 산업화 시기의 주요가치로는 성실, 근면, 자조, 협동을 제시할 수 있으며, 추구하는 인재상은 경제발전에 필수적이고 강력한 직업능력을 갖춘 기능인이었다. 민주화의 주요가치로는 참여, 평등, 공존을 제시할 수 있으며, 추구하는 인재상은 경제성장의 둔화라는 위기감 속에서 국가의 생존과 번영을 위하여 이바지하는 우수한 과학인재상이었다. 각 시기별 인재상은 실용적이면서도 실천적인 유형의 인간상이 드러나고 있으며 공동체적 덕성을 중시하고 있는데, 이는 전통적인 가치관의 연속선상에서 시기별 특징을 보여주고 있는 대목이기도 하다.

• 지역사회간호학회지
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• 제12권1호
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• pp.247-260
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• 2001

The objectives of this study are first, to investigate the significant differences in the perception and attitude for sexual role of workers, second, to identify the degree of the perception of women manpower in workplace, third, to identify the perception for sexual harassment in workplace and fourth to analyze the relative important factors that effect on conception for sexual harassment. The survey data were collected by questionnaires on May 2000, and the number of subjects was 300 workers. The SAS-PC program was used for the statistical analysis such as t-test, ANOVA and regression analysis. Major results were follow as: 1. The performance rates of health education for sexual harassment was 66%, and 58.9% of the lecturer of sexual harassment education was occupational health nurse. The 45.2% of workers acquired the information for sexual harassment through massive education in workplace. 2. The perception and attitude of sexual role was relatively positive as 2.3(SD=0.69) of mean values. and the difference by sex, age, marital status. and working period was significant. 3. The perception of the women manpower in workplace was generally positive as 7.9(SD= 3.25) of mean values, and the working experience group of less 10 years and more 10 years old age group showed the significant difference in comparative to other group. 4. The perception of sexual harassment of workplace composed of legal basis, range of victim, place of sexual harassment, type of sexual harassment. misconception of sexual harassment, and coping methods of sexual harassment. Among of these perception. type and coping methods of sexual harassment were shown high perception level. The difference by sex between group for perception of sexual harassment was highly significant. 5. Factors that effect on the perception of sexual harassment was not high for the explanation power of regression, but the age, the type of task, the. perception for women manpower were important variables. Based on this results of study, we recommend that the education of sexual harassment in workplace should be strengthened and specified according to age, working period, type of working task. It also should provide various education and information to workplace. Finally and there should be continuous education opportunity systematically to occupational health nurses who are major lecturers for sexual harassment, therefore they can educate workers more effectively.

• 한국콘텐츠학회논문지
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• 제19권10호
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• pp.59-68
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• 2019

최근 소비과정의 경험적 가치를 추구하는 소비 트렌드를 보이며, 도심 특급호텔의 핵심고객으로 변모한 내국인들의 특급호텔 이용의 지속적인 성장세를 위해서 내국인 고객이 추구하는 경험가치의 요인에 대한 연구가 필요하다. 연구 결과, 특급호텔 내국인 이용객의 경험가치 중, 환상성 요인이 이용만족의 주요 선행요인으로 확인되어, 특급호텔은 내국인 이용객이 선호하는 다른 세계 경험, 색다른 경험, 수준 높은 경험과 같은 감성적 가치를 위해 특별한 컨셉과 분위기를 반영하는 것이 중요한 과제로 확인되었다. 그리고 이익성이 이용만족에 정(+)의 영향을 미치는 선행요인으로 확인되어 경제적 효용에 대한 요구가 중요한 것으로 확인되었다. 이는 합리적 요금으로 충분한 혜택을 느낄 수 있는 가성비 좋은 상품개발의 필요성이 제기된다. 이용만족과 지속적 이용의도와의 관계에서 성별, 직업별 특성이 조절역할을 하는 것으로 나타났다. 즉, 이용만족 고객 중 남성, 그리고 전문직과 자영업 직업을 가진 고객들이 여성 및 타 직업 고객들 대비하여 지속적 이용의도를 높게 가지는 것으로 확인되었다. 이는 결국 경제력이 있는 고객이 특급호텔의 지속적 반복고객이 될 가능성이 높다는 결과로 나타나 우수소비계층을 집중으로 한 보다 차별화되고 특화된 상품개발, 서비스 및 분위기 연출 등의 마케팅 활동의 강화에 대한 필요성을 살펴볼 수 있었다.

• 한국학교ㆍ지역보건교육학회지
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• 제22권4호
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• pp.49-60
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• 2021

Objectives: Laboratories have various latent physical, chemical, biological, and ergonomical factors according to the diversification and fusion of research and development activities. This study aims to investigate the chemical exposure concentrations of college laboratories and evaluate their health risks, and use them as basic data to promote the health of college students. Methods: The sampling and analysis of harmful chemicals in the air in laboratories were performed using Method 1500 of the U.S. National Institute for Occupational Safety and Health (NIOSH)의 Method 1500. The harmful chemicals in the laboratories were divided into carcinogenic and non-carcinogenic chemicals. Risk assessment was performed using the cancer risk (CR) for carcinogenic chemicals and using the hazard index (HI) for non-carcinogenic chemicals. Results: The harmful chemicals in college laboratories consisted of acetone, diethyl ether, methylene chloride, n-hexane, ethyl acetate, chloroform, tetrahydrofuran, toluene, and xylenes. They showed the highest concentrations in laboratories A (acetone 0.001~2.34ppm), B (chloroform 0.95~6.35ppm), C (diethyl ether 0.08~8.68ppm), and D (acetone 0.07~14.96ppm). The risk assessment result for non-carcinogenic chemicals showed that the HI of methylene chloride was 2.052 for men and 2.333 for women, the HI of N-hexane was 4.442 for men and 5.05 for women. Thus, the HI values were higher than 1. The risk of carcinogenic chemicals is determined by an excess cancer risk (ECR) value of 1.0×10^-5, which means that one in 100,000 people has a cancer risk. The ECRs of chloroform exceeded 1.0×10^-5 for both men and women, indicating the possibility of cancer risk. Conclusion: College laboratories showed the possibility of non-carcinogenic health risks for methylene chloride, n-hexane, tetrahydrofuran (THF), toluene, and xylenes, and carcinogenic health risks for chloroform, methylene chloride. However, this study used the maximum values of measurements to determine the worst case, and assumed that the subjects were exposed to the corresponding concentrations continuously for 8 hours per day for 300 days per year. In consideration of the nature of laboratory environment in which people are intermittently exposed, rather than continuously, to the chemicals, the results of this study has an element of overestimation.

• 한국산업보건학회지
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• 제16권4호
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• pp.398-412
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• 2006

The purpose of this study is to investigate the relationship between the acceleration of vibration by the powered hand tools used in the shipbuilding industry, and to develop the prospective prevalence model for the hand-arm vibration syndrome among the shipbuilding workers.The acceleration levels and frequencies of six types of grinder were measured using the ISO5349 method along with the time of exposure to the vibration from the powered hand tools. Medical examination for 114 workers were performed using the cold provocation test. Comparisons were made between the estimated prevalence of hand-arm vibration syndrome from ISO5349 and the observed values from the medical examinations. By multiple regression, we developed the prospective prevalence model of hand-arm vibration syndrome produced by the hand tools used in the shipbuilding industry. 4 hour-energy-equivalent frequency-weighted accelerations were $6.23m/s^2$ in the grinding job done after welding, and $13.39m/s^2$ in the grinding job done before painting. The mean exposure time while holding powered hand tools was 4.64 hours. Prevalence rates of Raynaud's Phenomenon were 12.04% in the grinding after soldering, and 42.9% in the grinding before painting measured using the ISO5349 method. After exposure to vibration for 10.79 years, about a half of the workers in the grinding after welding could developed Raynaud's Phenomenon. For the workers in the grinding before painting, the latency was 5.02 years. The ISO equation for dose response relationship was not significantly correlated with observed recovery rates of finger skin temperatures, blood flows and amplitudes of nerve conduction velocities. A multiple regression model for dose-response relationship was proposed from the results. Recovery rate of the skin temperatures = -0.668+ 0.337 ${\times}$ 4 hour energy equivalent frequency-weighted accelerations + 0.767 ${\times}$ duration of vibration exposure(years) The validity was proved by multiple regression analysis after correlation transformation and regression results based on model-building data and validation data.

• 대한예방한의학회지
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• 제10권2호
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• pp.31-49
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• 2006

This study was undertaken to investigate the effects of Gyoaesamultang in pregnant rats and their fetuses. Female Sprague-Dawley rats were orally administered with the Gyoaesamultang at dose of 5mg/kg/day for 20 days. Pregnant rats were sacrificed at 20th day of gestation, and observed internal and reproductive organs. Approximately, live fetuses in the 20th day of gestation were randomly selected and fixed in 95% ethanol. To observe skeletal malformations, fetuses were stained with alcian blue and alizarin red S. Maternal body weight of Gyoaesamultang treated group has a tendency to increase compared to that of control group. There were no significant difference in internal and reproductive organs. There were no significant changes between two groups in blood chemistry and hematological values. There were no significant changes in number of corpus luteum, implantation, live fetuses and implantation rate, delivery rate, late resorption rate and sex ratio. But Gyoaesamultang administered group showed lower early resorption rate than the control group. Neonatal body weight and number of fetus of Gyoaesamultang group were increased to that of control group. The fetuses of dams treated with Gyoaesamultang didn't showed external malformation. Vertebral and sternal variations were observed in Gyoaesamultang group but, compared to the control, those variations were insignificant. The number of ribs, cervical, thoracic, and lumber were normal. The number of sacral and caudal vertebrae were increased. Fetuses treated with Gyoaesamultang showed significant difference in the number of caudal vertebra(P<0.01). From these results, it can be concluded that Gyoaesamultang showed no toxicity effects on maternal body weight, early resorption rate, and number of live fetuses. There were no significant changes in organ weight, hematological data, reproductive organs. Although skeletal variations were showed in vertebrate and sternum, Gyoaesamultang were shown insignificant changes in bone malformation.

• 한국산업보건학회지
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• 제20권1호
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• pp.47-52
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• 2010

Green tobacco sickness (GTS) is known as an occupational disease among tobacco harvesters, and a form of acute nicotine intoxication by the absorption of nicotine through the skin from the wet green tobacco plant. On the assumption that GTS may occur by inhalation as well as absorption of nicotine, we measured the airborne nicotine concentration in tobacco field and the processing room of tobacco leaves. We measured the airborne nicotine concentrations in the tobacco field and processing room between 13 and 30 July 2008. All sampling and analyses of airborne nicotine were conducted according to the manual of analytic methods of NIOSH 2551, and we sampled 2 times at 11 points in the tobacco field by area sampling. The sampling in the processing room of tobacco leaves was conducted at 3 points, and earlymorning dew was collected from the tobacco by wringing the moisture into specimen bottles. The airborne nicotine concentration [geometric mean (geometric standard deviation)] in the tobacco field in the P.M. was higher [49.2 mg/$m^3$ (1.3)] than the A.M. concentration [43.4 mg/$m^3$ (1.4)]. Similarly, the nicotine concentration in the processing room of tobacco leaves was 224.4 mg/$m^3$ (1.2), and the concentration of nicotine in the dew was 64.7 mg/${\ell}$ (1.7). Based on our results, the airborne nicotine concentration in the tobacco field and the processing room of tobacco leaves were 100 and 400 times higher than the occupational recommended values (TLV-TWA of 0.5 mg/$m^3$), respectively. In the future, it is hoped that epidemiologic studies and environmental measurements will be conducted for GTS which occurs by inhalation of nicotine. If GTS is confirmed to occur by inhalation of nicotine, respiratory and dermal protective equipment must be distributed.

• 한국산업보건학회지
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• 제16권1호
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• pp.36-43
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• 2006

The principal aim of this field study was to determine the concentrations and emissions of gaseous contaminants such as ammonia and hydrogen sulfide in the different types of pig buildings in Korea and allow objective comparison between Korea and the other countries in terms of pig housing types. This field study was performed from May to June and from September to October in 2002. Pig buildings investigated in this research were selected in terms of three criteria; manure removal system, ventilation mode and growth stage of pig. Measurements of concentration and emission of ammonia and hydrogen sulfide in the pig buildings were done in 5 housing types and the visited farms were 15 sites per each housing type. Concentrations of ammonia and hydrogen sulfide were measured at three locations of the central alley in the pig building and emission rates of them were estimated by multiplying the average concentration($mg/m^3$) measured near the air outlet by the mean ventilation rate($m^3/h$) and expressed either per pig of liveweight 75kg(mg/h/pig) or per area($mg/h/m^2$). Concentrations of ammonia and hydrogen sulfide in the pig buildings were averaged to 7.5 ppm and 286.5 ppb and ranged from 0.8 to 21.4 ppm and from 45.8 to 1,235 ppb, respectively. The highest concentrations of ammonia and hydrogen sulfide were found in the mechanically ventilated buildings with slats; 12.1 ppm and 612.8 ppb, while the lowest concentrations of ammonia and hydrogen sulfide were found in the pig buildings with deep-litter bed system(2.2 ppm) and the naturally ventilated pig buildings with manure removal system by scraper(115.2 ppb), respectively(p<0.05). All the pig buildings were investigated not to exceed the threshold limit values(TLVs) of ammonia(25 ppm) and hydrogen sulfide(10 ppm). The mean emissions of ammonia and hydrogen sulfide per pig(75kg in terms of liveweight) and area($m^2$) from pig buildings were 250.2 mg/h/pig and 37.8 mg/h/pig and $336.3mg/h/m^2$ and $50.9mg/h/m^2$, respectively. The pig buildings with deep-litter bed system showed the lowest emissions of ammonia and hydrogen sulfide(p<0.05). However, the emissions of ammonia and hydrogen sulfide from the other pig buildings were not significantly different(p>0.05). Concentrations and emissions of ammonia and hydrogen sulfide were relatively higher in the pig buildings managed with deep-pit manure system with slats and mechanical ventilation mode than the different pig housing types. In order to prevent pig farm workers from adverse health effect caused by exposure to ammonia and hydrogen sulfide in pig buildings, they should wear the respirators during shift and be educated sustainably for the guideline related to occupational safety.