• Environmental Analysis Health and Toxicology
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• v.27
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• pp.2.1-2.4
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• 2012

Objectives: This study is a cross-sectional study to investigate the frequency of humidifier and humidifier disinfectant usage in the general population. Methods: A questionnaire was applied to 94 subjects (46 male, 48 female) from the general population of Gyeonggi Province. The questionnaire consisted of 3 scales (general characteristics, 5 items about humidifier usage, 5 items about humidifier disinfectant usage). Results: Thirty-five (37.2%) of the 94 subjects use a humidifier and humidifier disinfectant usage was found to be 18.1%. The frequency of humidifier usage is 4.8 times per a week and the humidifier disinfectant usage is 2.4 times per a week. Humidifier usage rate was highest in January. and then tended to rise gradually from October. Conclusions: Although this study population was not representative, we can say that approximately 50 percent of the humidifier users use a humidifier disinfectant and the trend of using a humidifier has shown seasonality.

• Journal of Environmental Health Sciences
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• v.39 no.2
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• pp.105-116
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• 2013

Background: In Korea, there is low awareness of the respiratory health problems caused by the use of humidifiers, leading to a lack of governmental measures. Objectives: The objectives of this study were to review cases of varying degrees of humidifier lung and fever in connection with the use of humidifiers and to summarize the probable environmental agents causing these cases. Methods: We searched all articles reporting on humidifier lung, humidifier fever, and humidifier diseases caused by the use of a humidifier both at home and in the workplace. Results: We summarized a number of cases of varying degrees of respiratory diseases resulting from inhalation of water mist of humidifiers containing various species of bacteria and fungi and their toxins. Type of respiratory disease connected with humidifier lung includes interstitial pneumonitis, hypersensitivity pneumonitis, fever and several respiratory symptoms. Non-tuberculous mycobacteria (NTM), Actinomycetes, endotoxins and contaminated humidifier water were the most commonly suspected probable environmental agents causing humidifier lung. In Korea, the use of humidifier biocide is suspected as a likely cause of fatal lung injury including death and lung transplantation. Conclusion: Governmental policy should be devised and measures including a national surveillance system should be taken to prevent humidifier lung caused by the use of humidifiers.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.471-473
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• 2006

An object of the present study is to provide a hollow fiber membrane humidifier capable of improving the humidification efficiency while lowering the pressure loss, and is suitably usable for PEMFC(Polymer Electrolyte Membrane Fuel Cell). The performance of PEMFC is decisively dependent on the humidity of the electrolyte membrane(fluorinated membrane) and a humidifier plays an important role in moisturizing electrolyte membrane. Especially this humidifier is adaptable for lower price to promote the commercialization of fuel cell vehicles and is passive type to be power free and to be volumetrically optimized. In this research, we propose the substitutes for the expensive fluorinated materials and the optimum dry-jet wet spinning conditions of hollow fiber membrane to get the fuel cell humidifier. In addition to that we established the standard method of evaluating the moisturizing performance of the humidifier of various materials.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.177-179
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• 2007

An object of the present study is to provide a hollow fiber membrane humidifier capable of improving the humidification efficiency while lowering the pressure loss, and is suitably usable for PEMFC(Polymer Electrolyte Membrane Fuel Cell). The performance of PEMFC is decisively dependent on the humidity of the electrolyte membrane(fluorinated membrane) and a humidifier plays an important role in moisturizing electrolyte membrane. Especially, this humidifier is a passive type(power-free) item and is volumetrically optimized. In this research, we propose the substitutes for the expensive fluorinated humidifier materials and the optimum dry-jet wet spinning conditions of hollow fiber membrane. In addition to that, This study will present an performance of an humidifier and compare computational results with the experimental data.

• Journal of Environmental Health Sciences
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• v.47 no.4
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• pp.310-319
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• 2021

Background: Humidifier disinfectant exposure is an ongoing issue, and there is still considerable related controversy. Various approaches are needed to secure scientific evidence on the extent of the victims' damages and for the determination of appropriate compensation. Objectives: The purpose of this study was to assess the association between humidifier disinfectant (HD) use and academic achievement in Korean children. Methods: This study used data from the 8th Panel Study on Korean Children in 2015. For the final study, 1,598 cases were used. T-tests and multiple linear regression analyses were conducted to determine whether the use of humidifier disinfectant is a factor that affects academic ability. Results: Children in groups using humidifier disinfectant showed statistically significantly lower scores in all areas of language, including reading, speaking and writing, and statistically lower scores in all areas of mathematics, including counting, addition and subtraction. In the multiple regression analysis results, which control for the effects of various demographic/social variables, the use of humidifier disinfectants showed statistically significant beta coefficients (β: -0.357, p<0.001), negatively affecting children's language ability. As for the 'math' variable, which was created by combining counting, addition, and subtraction scores, the use of humidifier disinfectants as independent variables also showed statistically significant beta coefficients (β: -0.200, p<0.001), negatively affecting children's math ability. Conclusions: The results of the study showed that depending on whether or not humidifier disinfectants were used, there are differences in children's language abilities, such as reading, speaking, and writing, as well as in their mathematical abilities, such as counting, adding, and subtracting numbers. These findings are thought to serve as a scientific basis for extending the perspective from health effects to more diverse areas of demographic and social impact related to humidifier disinfectant damage and compensation.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.3
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• pp.310-315
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• 2009

This investigation was performed to study the characteristics of electricity and heat transfer that occur in the cylinder of electrode type humidifier during the process of water evaporation. Measurements were made to obtain the amount of water evaporation, the consumption of electric power, electrical conductivity, etc according to the materials and shapes of electrode. When the humidifier was in non-drain controlled mode, the number and amplitude of current cycle per minute increased gradually with the lapse of time, whereas for drain controlled mode, it decreased about 40[%] after draining water. It was found that for non-drain controlled mode, the thermal efficiency of humidifier which used SS400, STS316 and wire net electrode type was about 95~96[%] and it was 2~4[%] higher than that of drain controlled mode. Also, it was shown that the thermal efficiency of humidifier which used neighboring six-phase electrode balanced electrically was 4[%] higher than that of existing six-phase type.

• Journal of Environmental Health Sciences
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• v.44 no.2
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• pp.107-114
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• 2018

Objectives: The objectives of this study are to describe strategy for exposure assessment of humidifier disinfectant (HD) used in the national program to associate the use of HD with lung injury. Methods: Strategy and method employed to evaluate HD use characteristics were developed to associate health effects including HD associated with lung injury (HDLI). We developed HD-specific questionnaire to assess potential HD exposure, which was consistently used in the national program. Trained environmental health scientists visited the residences of registered subjects and investigated HD use characteristics. Results: Major HD exposure related variables were type of HD brand/s used; HD volume added to the humidifier, frequency of HD addition, and time spent in room/s with the humidifier; duration of HD use in the household in average months/year, weeks/month, and days/week; average sleeping hours in a room with an operating humidifier containing a disinfectant; number of HD brands used and type of HD; average distance of the bed from the humidifier in meters. Conclusions: We concluded that estimated airborne HD concentration was significantly associated with the risk of HDLI.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.98.2-98.2
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• 2011

For optimal performance of a proton exchange membrane fuel cell (PEMFC), the membrane electrode assembly (MEA) requires hydration, and the membrane's conductivity depends on water content. A humidifier is required to ensure that the reactant gas, usually hydrogen and air, is hydrated before entering the fuel cell. Dry membrane operation or improper hydration causes performance degradation. Typically, the humidification of a fuel cell is carried out by means of an internal or external humidifier. A membrane humidifier is applied to the external humidification of transportation or residential power generation fuel cell due to its convenience and high performance. In this study, The experiments were constructed with a plate-type membrane humidifier in terms of geometric parameters and operating parameters. The results show that the temperature and pressure, the channel length, the membrane thickness and gas flow rate are critical parameters affecting the performance of the humidifier.

• Journal of Wellbeing Management and Applied Psychology
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• v.5 no.4
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• pp.57-67
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• 2022

Purpose: The purpose of this study is to identify what research ethics issues are related to chemical incidents at the level of national disasters in Korea, and then to secure clear research ethics to prevent similar incidents from recurring. Research design, data and methodology: The study design was a case study of the humidifier disinfectant disaster in Korea. The humidifier disinfectant incident is a worldwide issue that has never occurred in the world. The main cause of the humidifier disinfectant incident that occurred only in Korea was the toxicity of the humidifier disinfectant contained in the humidifier spray. In this regard, research ethics will be derived through related laws and systems, research ethics status, incident damage and compensation, prosecution's investigation status, and the final precedent of the Supreme Court. Results: Although the lack of laws and systems of government departments related to humidifiers is important in the research results, the violation of ethics regulations by researchers during research experiments has become a decisive problem. Conclusions: In conclusion, the most important thing is that the research bioethics of researchers at the forefront should take precedence over any other values, especially during experiments and research related to public health.

• Journal of Environmental Health Sciences
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• v.44 no.5
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• pp.409-420
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• 2018

Objectives: An outbreak of humidifier disinfectant-related respiratory disease has not only been a massive disaster for end users, but it is also a concern for the workers of the manufacturers. This study presents the results of a questionnaire survey on the health effects among workers involved in the manufacture of humidifier disinfectants. Methods: Seven sites where humidifier disinfectants were manufactured were identified. A questionnaire survey was conducted to assess the physical symptoms experienced by workers related to humidifier disinfectants. Among a total of 177 workers, 42 subjects were available for the survey. Results: Twenty-one of the 42 respondents reported that they experienced respiratory or skin and mucosal irritation symptoms during work. Of the respondents who experienced symptoms, 14 believed that their symptoms were related to the work process and reported that the symptoms were experienced while working. However, no respondents reported ongoing symptoms or sequelae during the investigation period, and this result could not minimize selection bias due to low response rates. We then compared the characteristics of the group who experienced suspicious symptoms with those of the group without any symptoms. There was no statistically significant difference between two groups. Conclusions: We could not find significant health effects related to the humidifier disinfectant manufacturing process, although 21 respondents experienced stimulant symptoms and 14 respondents believed that the symptoms were related to the work process. Due to the long period of time after occupational exposure and the lack of data, there were many limitations to this study. However, this is one of the few follow-up investigations of workers related to this large-scale disaster in South Korea and the limitations of this study highlight the need to follow up with a nationwide database rather than an occasional survey.