• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.3
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• pp.256-262
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• 2014

Objectives: The purpose of this study was to identify the major volatile organic compounds generated during extrusion work with nylon 66 resin and evaluate causes of discomfort among extrusion workers. Methods: A thermal decomposition experiment using nylon 66 resin collected at a worksite was conducted in the laboratory. Based on hazards identified through the thermal decomposition experiment, the exposure levels of the workers were evaluated. Results: The major decomposition products were formaldehyde, acetaldehyde, aniline, cyclopentanone and diphenyl amine. These materials were identical to those sampled in the extrusion booth. The sources of the annoying smells, about which the workers had complained, were formaldehyde, aniline, diphenyl amine, and other hazards in the vapor and fine particles produced by the extrusion work. Formaldehyde, acetaldehyde, and aniline were detected from air samples among workers involved in extrusion work. However, the concentration levels were much lower than Korean occupational exposure limits. The average concentration levels of formaldehyde, acetaldehyde, and aniline were 0.0120 ppm, 0.0036 ppm and 0.0006 ppm, respectively. Conclusions: The extrusion process at around $300^{\circ}C$ thermally decomposes the nylon 66 resin, emitting formaldehyde, aniline, and other hazards, which might have made workers uncomfortable due to their smells. The workers exposure levels to volatile organic compounds were far lower than Korean occupational exposure limits. However, since formaldehyde is a human carcinogen and acetaldehyde and aniline are also confirmed animal carcinogens, it is recommended that exposure levels should be maintained at a minimum level.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.4
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• pp.582-589
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• 2019

Objectives: Although active pulmonary tuberculosis(active PTB) is manifested as one of the complications of pneumoconiosis, attacks of active PTB among patients with pneumoconiosis is still unexplored. The objective of the present study was to identify the attack rate of active PTB among workers in dusty environments who were diagnosed with pneumoconiosis. Methods: The study was performed using the results of the Pneumoconiosis Examination Council's assessment from the Korea Workers' Compensation and Welfare Service(KCOMWEL) database between January 1, 1984 and December 31, 2017. Pneumoconiosis was defined as Category 1 or more in the radiological findings of pneumoconiosis. Active PTB was defined as a positive result for active PTB in the results of the Pneumoconiosis Examination Council's assessment. Results: A total of 37,946 workers in dusty environments who received a health examination for diagnosing pneumoconiosis between January 1, 1984 and December 31, 2017 were selected as study subjects. The attack rate of active TB among subjects who were diagnosed with pneumoconiosis and those who were diagnosed without pneumoconiosis were 8.5% and 1.4%, respectively. In the multivariate logistic analysis including age, sex, radiological findings, complications, male[odds ratio(OR), 2.0; 95% confidence interval(CI), 1.4-3.1] and pneumoconiosis(OR, 6.5; 95% CI, 5.7-7.4) were associated with an increased risk of developing active PTB. Conclusions: The present study determined that dusty workers who were diagnosed with pneumoconiosis had a high rate of active PTB compared to TB patients and patients who were diagnosed with silicosis. Therefore, in addition to silicosis, it is necessary to include pneumoconiosis among the high-risk groups for TB.

• Safety and Health at Work
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• v.9 no.2
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• pp.164-171
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• 2018

Background: In recent years, the interest in health and safety in the workplace has increased. Agriculture is one of the human work activities with the highest risk indexes. Studies on risk perception of agricultural workers are often referred to as specific risk factors (especially pesticides), but the risk perception plays an important role in preventing every kind of accident and occupational disease. Methods: The aim of this research is to test a new method for understanding the relation between risk perception among farmers and the main risk factors to which they are exposed. A secondary aim is to investigate the influence of training in risk perception in agriculture. The data collection was realized using a questionnaire designed to investigate the risk perception; the questionnaire was given to a sample of 119 agricultural workers in central Italy. Through the use of the "principal components analysis" it was possible to highlight and verify the latent dimensions underlying the collected data in comparison with scales of attitudes. Results: Results show that the highest percentage of strong negative attitude is among the people who have worked for more years, while farmers who have worked for fewer years have a marked positive attitude. Conclusion: The analysis of the questionnaires through the synthetic index method (Rizzi index) showed that agricultural workers involved, in particular the elderly workers, have a negative attitude towards safety; workers are hostile to safety measures if they have not attended special training courses.

• Korean Journal of Veterinary Service
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• v.27 no.4
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• pp.335-343
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• 2004

Although human rabies deaths are rare, the disease remains a public health problem in Korea. Here we report the outbreaks and surveillance of animal rabies in Gangwon-do. Animal rabies infections were identified in 119 animals from 1993 to 2003. The $78\%$ of all rabid animals were domestic species in Gangwon-do. Wild Korean raccoon dog (N. p. koreensis) continued to be the only reported rabid wildlife species. Outbreaks of rabies infections in Korean raccoon dogs are found in broad geographic regions across the northern Gangwon-do. The principal rabies hosts today are probably wild animals in Gangwon-do. The malaise, cerebral dysfunction, anxiety, confusion, agitation and abnormal behavior of the animals were the important symptoms of the disease. The Encephalitis, infiltration with lymphocytes and polymorphonuclear leukocytes and the inclusion bodies (Negri bodies) in neuronal cells were the specific histopathological signs. The results of indirect fluorescent antibody test (IFA) for animal rabies diagnosis were identical and the technique was useful to diagnose the disease. Preexposure vaccination is recommended for persons in high-risk groups, such as laboratory workers, veterinarians and certain animal handlers.

• Industrial Engineering and Management Systems
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• v.7 no.2
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• pp.160-170
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• 2008

This paper proposes a mathematical model for converting conveyor assembly line to cellular manufacturing in complex production environments. Complex production environments refer to the situations with multi-products, variant demand, different batch sizes and the worker abilities varying with work stations and products respectively. The model proposed in this paper aims to determine (1) how many cells should be formatted; (2) how many workers should be assigned in each cell; (3) and how many workers should be rested in shortened conveyor line when a conveyor assembly line should be converted, in order to optimize system performances which are defined as the total throughput time and total labor power. We refer the model to a new production system. Such model can be used as an evaluation tool in the cases of (i) when a company wants to change its production system (usually a belt conveyor line) to a new one (including cell manufacturing); (ii) when a company wants to evaluate the performance of its converted system. Simulation experiments based on the data collected from the previous documents are used to estimate the marginal impact that each factor change has had on the estimated performance improvement resulting from the conversion.

• Safety and Health at Work
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• v.13 no.4
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• pp.421-428
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• 2022

Background: The exposure to solar ultraviolet radiation is a significant risk factor generally underestimated by outdoor workers and employers. Several studies have pointed out that occupational solar exposure increased eye and skin diseases with a considerable impact on the lives and productivity of affected workers. The main purpose of this study was to evaluate the effectiveness against ultraviolet radiation of some measures recently undertaken for the protection of lifeguards in a coastal area of Tuscany. Methods: Different shading structures (gazebos and beach umbrella) were tested during a sunny summer's day on a sandy beach by means of two radiometers; the UV protection offered by some T-shirts used by lifeguards was also tested in the laboratory with a spectrophotometer. Results: The analysed shading structures strongly reduced the ultraviolet radiation by up to 90%, however a not always negligible diffuse radiation is also present in the shade, requiring further protective measures (T-shirt, sunglasses, sunscreen, etc.); the tested T-shirts showed a very good-excellent protection according to the Australian/New Zealand standard. Conclusion: Results obtained in this study suggest how the adoption and dissemination of good practices, including those tested, could be particularly effective as a primary prevention for lifeguards who are subjected to very high levels of radiation for long periods.

• International Journal of Safety
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• v.5 no.1
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• pp.33-36
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• 2006

In laboratories, researchers frequently work using new methods with new tools and materials. So the workers in laboratories are exposed to risk from dangerous articles all the time. In the case of university laboratories, testing is done by the individual at night. Because of that, the risks in university laboratories are higher than in other places. In addition, students and managers in universities generally have little concern for laboratory safety. So students are sometimes injured or killed in laboratory accidents. In this study, 1,000 university students answered questions about university laboratory safety. Their answers have been analyzed to determine the state of actual conditions and to formulate countermeasures. The results indicate that we need to change the safety awareness of the universities and the students. Adequate safety training and safe practice must be implemented by each university to decrease accidents. Development of systematic safety training program suited to the specific conditions of the individual laboratory and formulation of specific counter plans should accidents occur are required.

• Korean Journal of Clinical Laboratory Science
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• v.55 no.1
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• pp.29-36
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• 2023

This study proposes a spirometry reference equation suitable for Asian migrant workers undergoing special health examinations. The study participants were divided according to their region: Central Asia, Northeast Asia, and South Asia Pacific. We confirmed results of the spirometry analysis of migrant workers and the interpretation consistency between the prediction equations. Based on this data, we propose a reference equation suitable for domestic migrant workers and suggest a scaling factor applicable to the spirometer wherein the reference equation is not easily applicable. The kappa-values obtained for men and women, respectively, between the global lung function initiative 2012 (GLI2012)-Southeast Asian and the Southeast Asian equations were 0.819 and 0.770, between the GLI2012-Southeast Asian and the South Asian equations were 0.881 and 0.866, and between the GLI2012-Northeast Asian and the Central Asian equations were 0.831 and 0.833. We propose applying the GLI2012-Northeast Asian equation for Northeast Asian and Central Asian countries, whereas the GLI2012-Southeast Asian equation was found to be more suitable for predicting Southeast Asian and South Asian populations. For spirometry, we recommend applying a scaling factor of 0.87 to the Dr. Choi equation, wherein the GLI2012-Southeast Asian equation is not applicable.

• Journal of Preventive Medicine and Public Health
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• v.28 no.2 s.50
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• pp.406-420
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• 1995

To study the health hazards and exposure status of manganese among female manganese workers, authors conducted airborne, blood and urine manganese concentration measurements, questionnaire and neurological examinations on 80 manganese-handling productive female workers(exposed group) in a manganese manufacturing facto in Pohang city and 127 productive female workers not handling manganese(control group) in other factories in the Pohang city. The results are; 1. Geometric mean concentrations of manganese in air and urine were $0.98mg/m^3\;and\;4.12{\mu}g/l$ and arithmetic mean concentration of manganese in blood was $6.94{\mu}g/dl$ in exposed group, significantly higher than those of control group(p<0.05). However, clinical and laboratory findings in exposed group were not statistically different from those of control group. 2. As age increase, positive rates of clinical symptoms also increased in the exposed group. However, in older aged group, the positive rates of symptoms and signs were statistically different from those of control group. We observed the same tendency in the positive rates of the neurological examinations. 3. There was statistically significant correlation between airborne and urine manganese concentrations(r=0.61, p<0.01) while there was no statistically significant correlation between airborne and blood manganese concentrations(r=0.29, p>0.05). The results suggest that urine manganese concentration was the best appropriate biomarker to estimate the exposure to manganese in respect to clinical symptoms and signs. In the analysis of correlation between urine and airborne manganese concentrations, it is required to adjust the present permissible exposure level(PEL) of airborne manganese.

• Journal of the Korean Institute of Gas
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• v.11 no.1 s.34
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• pp.18-22
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• 2007

The fault current through the earth originated from a power line ground fault might cause arcing through the soil to an adjacent pipeline, which might bring about not only a catastrophic accident such as gas explosion and oil leakage but also a hazard to the safety of workers responsible for the maintenance and repair of the pipeline. In this paper we investigated the arcing phenomena through soil between a power line tower and a pipeline and outlined the standards for the separation distance of a buried pipeline adjacent to the power line tower.