• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.3
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• pp.278-288
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• 2019

Objectives: The objectives of this study are to summary controversy over health risks among semiconductor workers, to review major cancer risk results conducted in semiconductor operation and to evaluate occupational health activities in Korea for controlling hazardous agents generated in semiconductor operations Methods: Major occupational health issues that has been social controversies among semiconductor workers since 2007 were reviewed through an extensive literature, report and article review. Results: Since a female semiconductor worker aged 22 died from leukemia in 2007, job-association of a number of former semiconductor workers with various types of cancer and rare diseases have been denied by the Korea Workers' Compensation and Welfare Service (KWCWS), but some of them were later awarded compensation as an occupational disease by the administrative court. Two epidemiologic cancer risk studies conducted in Korea found increased risks in leukemia and non-Hodgkin's lymphoma among semiconductor workers. Various legal occupational health activities taken in semiconductor industry were found to fail to assess a complex characteristics of semiconductor operations, such as drastic changes in chemical use, processes, and technology, multiple exposure. National compensation regulation also showed the limitation to evaluate job-association of semiconductor workers who had worked in semiconductor operation. Conclusions: National legal measures should be taken to improve several occupational health activities and duties for protecting workers. In addition, the KWCWS program should be revised so that all workers who meet minimal job or environment associations can be compensated.

• Safety and Health at Work
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• v.10 no.3
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• pp.347-354
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• 2019

Background: The aim of this study was to describe the types of diseases that developed in semiconductor workers who have registered with the Korea Workers' Compensation and Welfare Service (KWCWS) and to identify potential common occupational characteristics by the type of claimed disease. Methods: A total of 55 semiconductor workers with cancer or rare diseases who claimed to the KWCWS were compared based on their work characteristics and types of claimed diseases. Leukemia, non-Hodgkin lymphoma, and aplastic anemia were grouped into lymphohematopoietic (LHP) disorder. Results: Leukemia (n = 14) and breast cancer (n = 10) were the most common complaints, followed by brain cancer (n = 6), aplastic anemia (n = 6), and non-Hodgkin lymphoma (n = 4). LHP disorders (n = 24) accounted for 43%. Sixty percent (n = 33) of registered workers (n = 55) were found to have been employed before 2000. Seventy-six percent (n = 42) of registered workers and 79% (n = 19) among the registered workers with LHP (n = 24) were found to be diagnosed at a relatively young age, ${\leq}40years$. A total of 18 workers among the registered semiconductor workers were finally determined to deserve compensation for occupational disease by either the KWCWS (n = 10) or the administrative court (n = 8). Eleven fabrication workers who were compensated responded as having handled wafers smaller than eight inches in size. Eight among the 18 workers compensated (44 %) were found to have ever worked at etching operations. Conclusion: The distribution of cancer and rare diseases among registered semiconductor workers was closely related to the manufacturing era before 2005, ${\leq}8$ inches of wafer size handled, exposure to clean rooms of fabrication and chip assembly operations, and etching operations.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.1
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• pp.32-41
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• 2012

Objectives: Information of chemical in electronics industry has not been known enough, although workers' health hazards by chemicals in this industry have been regarded serious. The who always contribute to reveal and control the health hazards and risks in electronics industry have not been the industry but the occupational or environmental victims and grassroot organizations. The similar phenomena can be observed in Korea. Methods: The experiences of individual workers on the occuapational safety and health in semiconductor factory were heard separately and integrated with related literatures. Results:: The first part of this article is largely based on the memories and experiences of individual workers of semiconductor factories, mainly from S semiconductor. Common features of those experiences can be a good resource for detail understanding of the workplace, especially under the situation without any transparent disclosure of information by the governments or the companies. The second part of this article deals with several factors to be considered for control of exposure in workplace; characteristics of workplace and workforce, types of chemicals used, and the way of using the chemicals. Then the current social issues on work-relatedness of cancers of S semiconductor workers are presented briefly. Conclusions: As a conclusion, current OSH situations and issues in Korean electronics industry raise the need of changes in OSH culture. General adaptation of precautionary principle, internalization of costs, and extended responsibility of producers are needed urgently. The OSH professionals both in public and private sectors should support these agendas under their social obligation to protect workers' health.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.1
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• pp.42-51
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• 2012

Objectives: To compare the exposure level of extremely low frequency (ELF) magnetic fields among semiconductor workers, shipyard welders and office workers. Methods: To measure the ELF magnetic field concentration, EMDEX LITE (Enertech, USA) were used and monitored for eight hours continuously. Five companies handling the electric and magnetic field (EMF) source were investigated, which the exposure groups were classified into three groups: semiconductor workers, welders, and office workers. Welder group was chosen as a high exposed group and office group as a low exposed group. Results: The arithmetic mean (${\pm}SD$) and geometric mean (GSD) of personal exposure level of semiconductor workers were 0.73 (${\pm}1.33$) ${\mu}T$, 0.43 (2.88) ${\mu}T$, respectively. The ceiling value ranged between 0.18 and 123.2 ${\mu}T$. Welders were exposed high with the arithmetic mean value of 3.46 (${\pm}\;13.46$) ${\mu}T$ and geometric mean value of 0.45 (4.70) ${\mu}T$, respectively, and ceiling value range of 75.5~129.6 ${\mu}T$. The exposure levels of office workers were low compared to other exposed groups; the arithmetic mean 0.05 (${\pm}0.13$) ${\mu}T$, geometric mean 0.03 (2.38) ${\mu}T$ and ceiling value range 0.37~3.35 ${\mu}T$. This study revealed statistically significant differences of the mean ELF magnetic field exposure doses among three groups (p < 0.01). Conclusions: The average ELF magnetic field exposure doses of semiconductor workers were much higher than those of office workers in control group, but were lower than those of welders in high exposure group.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.3
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• pp.272-280
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• 2014

Objectives: The purpose of this study was to evaluate the characteristics of worker exposure to hazardous chemical substances and propose the direction of work environment management for protecting worker's health in the semiconductor assembly process. Methods: Four assembly lines at two semiconductor manufacturing companies were selected for this study. We investigated the types of chemicals that were used and generated during the assembly process, and evaluated the workers' exposure levels to hazardous chemicals such as benzene and formaldehyde and the current work environment management in the semiconductor assembly process. Results: Most of the chemicals used at the assembly process are complex mixtures with high molecular weight such as adhesives and epoxy molding compounds(EMCs). These complex mixtures are stable when they are used at room temperature. However workers can be exposed to volatile organic compounds(VOCs) such as benzene and formaldehyde when they are used at high temperature over $100^{\circ}C$. The concentration levels of benzene and formaldehyde in chip molding process were higher than other processes. The reason was that by-products were generated during the mold process due to thermal decomposition of EMC and machine cleaner at the process temperature($180^{\circ}C$). Conclusions: Most of the employees working at semiconductor assembly process are exposed directly or indirectly to various chemicals. Although the concentration levels are very lower than occupational exposure limits, workers can be exposed to carcinogens such as benzene and formaldehyde. Therefore, workers employed in the semiconductor assembly process should be informed of these exposure characteristics.

• Safety and Health at Work
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• v.12 no.3
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• pp.403-415
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• 2021

Background: This study aimed to assess the possibility of benzene exposure in workers of a Korean semiconductor manufacturing company by reviewing the issued patents. Methods: A systematic patent search was conducted with the Google "Advanced Patent Search" engine using the keywords "semiconductor" and "benzene" combined with all of the words accessed on January 24, 2016. Results: As a result of the search, we reviewed 75 patent documents filed by a Korean semiconductor manufacturing company from 1994 to 2010. From 22 patents, we found that benzene could have been used as one of the carbon sources in chemical vapor deposition for capacitor; as diamond-like carbon for solar cell, graphene formation, or etching for transition metal thin film; and as a solvent for dielectric film, silicon oxide layer, nanomaterials, photoresist, rise for immersion lithography, electrophotography, and quantum dot ink. Conclusion: Considering the date of patent filing, it is possible that workers in the chemical vapor deposition, immersion lithography, and graphene formation processes could be exposed to benzene from 1996 to 2010.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.1
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• pp.9-19
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• 2012

Objectives: The aim of this study is to critically review the exposure surrogates and estimates used to associate health effects in wafer fabrication workers such as spontaneous abortion and cancer, as well as to identify the limitations of retrospective exposure assessment methods Methods: Epidemiologic and exposure-assessment studies of wafer fabrication operations in the semiconductor industry were collected. Retrospective exposure-assessment methods used in cancer risk and mortality and reproductive toxicity were reviewed. Results: Eight epidemiologic papers and two reports compared cancer risk among workers in wafer fabrication facilities in the semiconductor industry with the risk of the general population. Exposure surrogates used in those cancer studies were fabrication(vs. non-fabrication), employment duration, manufacturing eras, job title (operator vs. maintenance worker) and qualitative classifications of agents without assessing specific agent or job-specific exposure. In contrast, specific operation, job title and agents were used to classify the exposure of fabrication workers, contributing to finding a significant association with spontaneous abortion (SAB). Conclusion: Further epidemiologic studies of fabrication workers using more refined exposure assessment methods are warranted in order to examine the associations between fabrication work, environment, and specific agents with cancer risk or mortality as used in SAB epidemiologic studies.

• Safety and Health at Work
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• v.9 no.3
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• pp.249-256
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• 2018

This article aims to provide a systematic review of the exposure assessment methods used to assign wafer fabrication (fab) workers in epidemiologic cohort studies of mortality from all causes and various cancers. Epidemiologic and exposure-assessment studies of silicon wafer fab operations in the semiconductor industry were collected through an extensive literature review of articles reported until 2017. The studies found various outcomes possibly linked to fab operations, but a clear association with the chemicals in the process was not found, possibly because of exposure assessment methodology. No study used a tiered assessment approach to identify similar exposure groups that incorporated manufacturing era, facility, fab environment, operation, job and level of exposure to individual hazardous agents. Further epidemiologic studies of fab workers are warranted with more refined exposure assessment methods incorporating both operation and job title and hazardous agents to examine the associations with cancer risk or mortality.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.1
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• pp.1-8
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• 2012

Objectives: The aim of this study is to review occupational hygiene activities, including work environment measurement as required by the industrial safety and health laws of Korea, and suggest improvements required to establish an effective exposure surveillance system. Methods: The controversial limitations of exposure surveillance examining the work-association of several types of cancers in semiconductor workers were reviewed. Results: The bulk of the exposure surveillance system was found to focus purely on work environment measurements without providing other important exposure surrogates, such as job title, operation, exposure duration, etc. The current work environment measurement system is limited in terms of the efficient assessment of the exposure status of workers due to a lack of exposure information. Conclusion: The introduction of a national standard classification of occupations and job titles into the exposure and health effect surveillance system should be discussed in order to retrospectively assess exposure characteristics.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.1
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• pp.26-31
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• 2012

Objectives: To review the occurrence of cancer cluster in S Electronics semiconductor factories, process of epidemiological researches and lawsuit for industrial accident compensation. Methods: Occupational Safety and Heatlh Research Institute (OSHRI) epidemiological research report, Seoul National University (SNU) field survey report and Seoul Administrative Court ruling were investigated. Result:: OSHRI denied the association between working environment and outbreak of cancers, but SNU survey team reported that carcinogens do exist in workplace and the workers are exposed to them. Seoul Administrative Court ruled that 2 victims got cancer due to hazardous chemicals in working environment and be compensated but 3 victims were not acknowledged. Conclusions: Procedure of current OSHRI epidemiological research should be reassessed by the purpose of Occupational Accident Compensation Insurance Law.