• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.3
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• pp.229-242
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• 2013

Objectives: This study was designed to investigate the current status of the association of job-related information such as employment status, workplace environment, and hazard material exposures with health examination outcomes. Methods: The study used data from KNHANES 2007-2009 representing the three years of 2007-2009, which was conducted annually using a rolling sampling design that involved a complex, stratified, multistage, probability-cluster survey of a representative sample of the non-institutionalized civilian population in Korea. The final analytical sample consisted of 17,240 participants. Information on age, education, smoking history and alcohol intake was collected during the health interview. Job related information consisted of employment status, workplace environment, and hazardous material exposure. The selected indices of health examination were blood pressure, fasting glucose, blood cholesterol, HDL, SGOT, SGPT, and BUN. Results: In multiple logistic regression analysis using hypertension and pre-hypertension as dependent variables and job related categories as independent variables after covariate adjustments, the odds of hypertension and pre-hypertension were significantly lower in those with responsibility and power in their job activities. Interestingly, low odds for hypertension were observed among those who reported that their jobs were fast-paced. Conclusions: This study confirmed that some job-related categories in employment status, workplace environment, and hazardous material exposure had an association with health outcome status. It is worthwhile to comment that high responsibility and power in job activities were revealed as one of the important favorable factors to improve health condition of workers.

• Journal of the Korean Society of Safety
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• v.15 no.1
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• pp.72-79
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• 2000

In recent, occupational diseases in harmful working places become a social issue. It is the well-known fact that a respiration in polluted working places exert a serious effect on health of workers. Accordingly, the cutting off contaminants air originally is the best way to improve working environments. In these cases, ventilation systems should be essentially installed to dilute or exhaust the contaminated indoor air. In this study, we investigated the characteristics of ventilation system of the noxious gas in working indoor places with natural ventilation by using COMET. The numerical simulations were carried out the natural ventilation with two phase(air, dust). For turbulent flow, Reynolds stresses were closed by the standard $\kappa$-$\varepsilon$ model. The results are as follows ; 1) In the natural exhaust in the working place, the flows of the central region have a more rapid velocity vector than the right and left one. 2) Numerical results show that the distribution of contaminants concentration have greater influence on convection than the case of diffusion by government of velocity vectors. 3) To observe the velocity variation with distance, three location of distance are considered. As results, it shows that the velocity are 0.075(m/s) at y=5(m), 10(m) and mean concentration are raised 10.6% at y=5(m), 10(m). 4) We have presented the useful data for the adequate counterplan in the harmful working places by carrying out the various investigation of the natural ventilation.

• Journal of Radiation Protection and Research
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• v.31 no.2
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• pp.53-63
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• 2006

The increased risk of cancer with exposure to low-dose radiation was estimated through longitudinal study for radiation workers at the nuclear power plants in Korea. The radiation dose data were collected from the Radiation Safety Management System(RSMS) of the Korea Hydro & Nuclear Power Co., Ltd(KHNP). The cancer risks with radiation exposure were evaluated in terms of relative mortality ratios(RMR) and relative incidence ratios(RIR) to the unexposed employees at the nuclear power plants, and of the standardized mortality ratios(SMR) and standardized incidence ratios(SIR). There were no significant increases of canters of all sites in the exposed group either in RIR[1.08, 95% confidence interval(CI) 0.74-1.58] or in RMR[1.21, CI 0.70-2.08]. Neither SIR[0.81, CI 0.28-0.96] nor SMR[0.86, CI 0.66-1.10] significantly deviated from 1.0 for cancers of all sites. The trend analysis did not identify evident dose-response relationship due to insufficient numbers of the cases. Consequently, it is concluded that increases in cancer risks in the radiation worker group exposed to low doses at the nuclear power plants in Korea are not identified at this time.

• Journal of Radiation Protection and Research
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• v.47 no.1
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• pp.1-7
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• 2022

Background: In Japan, new regulations that revise the dose limit for the lens of the eye (hereafter the lens), operational quantities, and measurement positions for the lens dose were enforced in April 2021. Based on the international safety standards, national guidelines, the results of the Radiation Safety Research Promotion Fund of the Nuclear Regulation Authority, and other studies, the Working Group of Radiation Protection Standardization Committee, the Japan Health Physics Society (JHPS) developed a guideline for radiation dose monitoring for the lens. Materials and Methods: The Working Group of the JHPS discussed the criteria of non-uniform exposure and the management criteria set not to exceed the dose limit for the lens. Results and Discussion: In July 2020, the JHPS guideline was published. The guideline consists of three parts: main text, explanations, and 26 examples. In the questions, the corresponding answers were prepared, and specific examples were provided to enable similar cases to be addressed. Conclusion: With the development of the guideline on radiation dose monitoring of the lens, radiation managers and workers will be able to smoothly comply with revised regulations and optimize radiation protection.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.1
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• pp.50-62
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• 2003

Exposure to metalworking fluids (MWFs) has significantly been associated with cancer developed in multi-organs, respiratory diseases and skin diseases. Several carcinogens to humans or animals are contained in MWFs. They have been reported to be mineral oils, polynuclear aromatic hydrocarbons (PAHs), formaldehyde and N-nitrosodiethanolamine (NDELA). The great hazards of MWF have forced the advanced country including United States to regulate carcinogens contained in MWF. In 2001, American Conference of Governmental Industrial Hygienists (ACGIHs) regarded MWF mist as suspected carcinogen to human (A2) and added it to “Notice of Intended Change (NIC)” list of 2001. In spite of the fact that much MWF has widely been used in many industries using machines, Korea has no legal actions for management of MWF. What is worse, even toxicity such as Carcinogenicity has not been reported. KS (Korean Standards) lists 7 advices of MWF but it does net state the hazards to health. It is very hard to control or minimize worker's exposure to MWF containing many carcinogens. Prier to the introduction of MWF to workplace, it is the most effective measure to regulate carcinogens below a certain level. Regulation on the content of PAH seems to be necessary because less amount of PAH in mineral oils improves the quality of MWF. Also, addition of nitrosating groups to MWF should be prohibited to minimize worker's exposure to NDELA. Employers and manufacturers should indicate the Carcinogenicity of all carcinogens in MWFs in Material Safety Data Sheets (MSDS) in order fer workers to recognize Carcinogenicity. Legal actions have to be taken to protect workers from health hazards due to exposure to MWF by further investigation on MWF.

• Journal of the Ergonomics Society of Korea
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• v.32 no.3
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• pp.259-266
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• 2013

Objective: This study aims to evaluate the workloads of industrial and automobile storage battery industries and their association to biological exposure indices. Background: Occupational lead exposure at battery manufacturing workplace is the most serious problem in safety and health management. Method: We surveyed 145 workers in 3 storage battery industries. Environmental factors(lead in air, temperature, humidity and vibration)), biological exposure indices(lead in blood and zinc protoporphyrin in blood) and individual workload factors(process type, work time, task type, weight handling and restrictive clothing) were measured in each unit workplace. Results/Conclusion: Air lead concentration is statistically significant in associations with workload factors(process type, work time, task type, and restrictive clothing) and environmental factors (humidity and vibration), whereas zinc protoporphyrin in blood are significantly associated with work time and weight handling. And lead in blood is significantly associated with work time, weight handling and temperature. Application: The results of this study are expected to be a fundamental data to job design.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.4
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• pp.375-382
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• 2013

Down through the years, human needs and desires have required a robot system to work at hazardous environments instead. Current painting task is costly and laborious, and it exposes workers to significant health and safety risks. Automation system offers potential improvement in this area and is especially well suited to the outer-wall painting tasks in concrete structures. This paper introduces the result of gondola-type building management robot(G-BMR) platform and mechanism for moving/tasking on building outer-wall for the outer-wall painting. Its technical and economic feasibility are conducted, and it is concluded that developing G-BMR is physically and economically feasible in this research. And we discuss about the future of G-BMR and automation in construction field.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.5
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• pp.825-831
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• 2023

The propellers used for big ships have a large diameter and are very heavy. In order to apply a precise and safe work process to them, it is necessary to use an exclusive turning system. For this reason, various techniques are applied to produce them. However, workers' convenience and safety are not taken into consideration enough at production sites. Conventionally, these propellers are designed to be separated as their turning system is loaded and rotated by empty weight. Therefore, it is necessary to replace such a design. This study tries to find the weaknesses of the design and structure of a conventional propeller turning system for large ships, to verify structure integrity of a structure in structural analysis, and to devise a plan for designing a new type of turning system. In the basic concept design and structural analysis for the turning system used in the propeller finishing process for large ships, this study drew the following conclusions. It was possible to develop the work process of the turning system for the propeller finishing process used for large ships, to obtain the dimensions for exterior design through a basic design. Structural analysis was conducted to find the structure integrity of the turning system. As a result, in the rail installed to transfer a gantry, the maximum stress was about 45MPa, about 5.5 times lower than the yield strength 250MPa. Therefore, the turning system was judged to be safe structurally.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.9 no.2
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• pp.19-31
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• 1999

Most breakthrough tests are conducted at higher concentration levels compared to those in the field of air-purifying respirator applications. For example, typical challenge concentrations for breakthrough tests agains tcarbon tetrachloride are ranged between 250-1000 ppm although applicable concentrations range for air-purifying cartridge is 5-50 ppm for carbon tetrachloride. However, no guarantee has been made that isotherms derived from the experiment at high challenge concentrations could estimate adsorption capacity at the lower concentration range where workers wear usually air-purifying respirators. Three models of adsorption isotherms (Freundlich, Langmuir and Dubinin/Radushkevich(D/R) isotherms) that have been commonly applied for respirator cartridge testing were evaluated. Adsorption capacity at each challenge concentration was calculated from the Reaction Kinetic equation fitted for the breakthrough data. These data were used for derivation of three isotherms. In general, the D/R isotherm has given the best agreement between estimated adsorption capacities and experimentally measured. If the challenge concentration of 100 ppm is included for derivation of models, Freundlich and D/R models could succes sfully produced good estimations for adsorption capacities at 50 ppm level. Estimated adsorption capacities by both models ranged in 94 - 109 % of the experimentally measured. However, Langmuir model gives underes timation in all cases.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.1
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• pp.21-26
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• 2019

Objective: The aim of this study is to analyze an excess trend for domestic permissible exposure limit of trichloroethylene based on previous literature review. Materials and Methods: The research object is a trichloroethylene among 13 chemical substances regulated with PEL(Permissible Exposure Limit) in Occupational Safety and Health Act. The information utilized from this study is the work environment measurement data from 2004 to 2013. The highest level among concentration data measured at various workplaces was selected as a representative value through data process. N.D. (Not Detected) data was considered as 1/2 of LOD(Limit Of Detection). Results: Among work environment measurement data between 2004 and 2013, the highest number of excess workplace and excess rate(24 sites & 1.15%) was observed in 2008's data when applying the PEL(50 ppm) of trichloroethylene. When they are compared with the ACGIH's TLV-TWA(10 ppm), 2008's data showed the highest number of excess workplace and excess rate(175 sites & 8.37%). The number of excess workplace and excess rate related to PEL of trichloroethylene showed increase trend in 2005 but tended to decrease after 2008. Conclusions: Based on the results obtained from this study, the exposure level of trichloroethylene in case of domestic workers is not considered as a safe phase regardless of the year of work environment measurement year. Thus, a strictly preventive management in workplace should be provided for reducing exposure level of trichloroethylene.