• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.4
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• pp.419-426
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• 2023

Objectives: This study aims to develop an Occupational Safety and Health (OSH) guide for the safe cleaning of contaminated machinery, equipment, and parts used in the electronics manufacturing process. Methods: A literature review, field investigations, and discussions were conducted. An initial draft of an OSH guide was developed and reviewed by experts with significant experience in maintenance work in the electronics manufacturing process in order to refine the guide. Results: Workers involved in cleaning processes with chemicals, solvents, and abrasive blasting can face exposure to a wide range of chemicals, abrasives, and noise. Identifying potential risks associated with each cleaning technique was an essential first step toward enhancing safety measures. The OSH guide comprises approximately eleven to twelve sections spanning 20-25 pages. It includes engineering and administrative protocols systematically organized to address the necessary actions before, during, and after cleaning tasks, depending on the technique. It is recommended that airline respirator masks be used in conjunction with an air purification system to ensure adherence to air quality standard "D" for atmosphere level. The use of an oil-free air compressor is advised, preferably a stationary model that does not rely on fuel sources like diesel. Conclusions: This OSH guide is designed to protect workers involved in maintenance activity in the electronics industry and aligns with global standards, such as those from the International Organization for Standardization (ISO) and Semiconductor Equipment and Material International, ensuring a higher level of safety and compliance.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.323-330
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• 1999

Daylight collapse have been occurred by about 5.0m deep at ground surface and collapse of the crown head part of the tunnel have connected to the ground surface during first step of shotcrete work after blasting of upper half section of the tunnel driving at two-way double track tunnel face section on highway construction. This study is for a successful illustration case for the earth improvement method through applying such strengthening methods as cement milk grouting, S.G.R grouting,, steel pipe reinforced multi-step grouting etc. for the purpose of earth strengthening of loosened earth block occurred by tunnel collapse.

• Journal of the Korean Society of Safety
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• v.16 no.1
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• pp.79-83
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• 2001

Posture of the upper limbs in field works is known to be an important risk factor associated with CTD(Cumulative Trauma Disorders). In particular, uncomfortable posture and highly repetitive works in shipbuilding industry(for instance, sand blasting, grinding and blast painting, etc) made workers exposed to a great risk of injuries. The purpose of this paper is to analyze recruitment pattern of the muscles according to posture(joint angle displacement) during grinding. In this study, EMG signals of pectoralis major, latissimus dorsi, and posterior deltoid muscle were measured and analyzed from FlexComp EMG solution. And subjective ratings of perceived exertion were made using Borg's CR-10 rating scale.

• Journal of the Korean Professional Engineers Association
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• v.33 no.3
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• pp.30-34
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• 2000

In recent years, disputes are on the increase that noise and vibration by construction equipments and blasting do damage to livestock farming families around construction sites in the construction of a road or a railway. Therefore, the following ways of improvement were presented in solving the existing problems of livestock disputes. $.$ To minimize the damage of livestock farming families by effect assessment of noise and vibration in the region expected to be damaged before the start of construction $.$ To maintain a thorough management system that can reduce noise and vibration during construction work $.$ To apply an adequate measurement method of noise and vibration taking field conditions into consideration

• Advances in concrete construction
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• v.7 no.3
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• pp.191-201
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• 2019

Bamboo concrete bond behaviour is investigated through pullout test in this work. The bamboo strip to be used as reinforcement inside concrete is first treated with chemical adhesive to make the bamboo surface impermeable. Various surface coatings are explored to understand their water repellant properties. The chemical action at the bamboo concrete interface is studied through different chemical coatings, sand blasting, and steel wire wrapping treatment. Whereas mechanical action at the bamboo concrete interface is studied by developing mechanical interlock. The result of pullout tests revealed a unique combination of surface treatment and grooved bamboo profile. This combination of surface treatment and a grooved bamboo profile together enhances the strength of bond. Performance of a newly developed grooved bamboo strip is verified against equivalent plain rectangular bamboo strip. The test results show that the proposed grooved bamboo reinforcement, when treated, shows highest bond strength compared to treated plain, untreated plain and untreated grooved bamboo reinforcement. Also, it is observed that bond strength is majorly influenced by the type of surface treatment, size and spacing of groove. The changes in bamboo-concrete bond behavior are observed during the experimentation.

• Explosives and Blasting
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• v.29 no.1
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• pp.17-26
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• 2011

In this study, the pollutants contained in water and soil samples taken from the explosive demolition site were examined to investigate the effects on environment, and management plan of non-point source pollution in the demolition site was suggested through characterizing the movement of the pollutant with time. As results, pH value of the water and soil samples after the demolition work was 8.5~9.3 which exceeds the Korean environmental criterion of water and soil range due to calcium hydroxide compounds in the concrete. The concentration level of heavy metals caused by the explosive demolition doesn't exceed the environmental criterion of water and soil doesn't exceed the environmental criterion of water and soil quality, and the influence of water and soil pollution on the environment was not considered. The concentration of the heavy metals was analyzed and that of Cr, Cu, Zn and Hg among the heavy metals increased after the drilling and explosive demolition. This says that concentration of the heavy metals during explosive demolition works needs to be monitored. The most pollutants with time or rain dilution into the demolition site decreased and this means that the pollutants caused by the explosive demolition might have influenced to vicinity of the demolition sites as non-point pollution.

• Explosives and Blasting
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• v.27 no.1
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• pp.62-78
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• 2009

Recently, construction techniques have been rapidly developed with reconstruction of old buildings, urban regeneration and efforts of restoring natural ecology, so demolition of deteriorated buildings has been rapidly increasing. Demolition work of building should be executed without damaging surrounding environments according to relevant regulations. There are various demolition methods and among them, explosives demolition is the most practical way for expenses and safety of work. As a part of Daejeon stream ecological restoration project, this thesis is a case of executing demolition of Chung-Ang Department Store which was built 35 years ago as covered structure on the upper part of Daejeon stream with explosives demolition. This structure is 8 stories high, total height of 41.6 m including basement floor, $1,650m^2$ for building area and $18,351m^2$ for total floor area. It is located in the center of Daejeon city where shopping centers and buildings are crowded and main facilities are Daejeon subway (18m), backside shopping center (20m), underground shopping center(15m), Mokchuk bridge, Eunjung bridge(0.25m) and fiber-optic cable(0.25m). In this project, implosion was selected for explosives demolition methods by considering this area being a busy urban area, and this project was executed after examining collapse movement of structure in advance using simulation program not to damage main facilities. Total 80kg of explosives and 1,000 detonators were being used. This project will be a good case of executing explosives demolition successfully by applying implosion on urban area in the country.

• Journal of Preventive Medicine and Public Health
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• v.31 no.3 s.62
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• pp.404-413
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• 1998

This study was conducted in order to clarify the factors affecting the number of utilization to health center for the shipyard workers who have been work in exposed environment to solvent. At first the tendencies of the number of utilization to health conte. in accordance with cumulative exposure(CE), lifetime weighted average exposure(LWAE), one's place of duty, work contents, states of using safety apparatus, the degree of the knowledge on handling solvents, exposure year. 1). The increase in the cumulative exposure(CE) war significantly higher in the number of utilization to health center. The group with longer exposure year showed significantly higher number of utilization to health center(p<0.01). Considering the work contents such as power blasting, spray, mixing and touch-up, the group of touch-up showed higher number of utilization to health center and this difference was statistically significant(p<0.001). Those who were not using the safety apparatus, showed higher number of utilization to health center, which was statistically significant(p<0.05). The degree of the knowledge on handling the solvent had no relation with using health center. 2) The results conducted from this study by multiple regression analysis in clarifying the factors affecting the number of utilization to health center, CE, exposure year and using safety apparatus was significant factor in utilization of health center.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.3
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• pp.39-49
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• 2021

The Korean Air-Force aircraft maintenance depot paints the exterior of various aircraft, including high-tech fighters. Aircraft exterior painting is a maintenance process for long-term life management by preventing damage to the aircraft surface due to corrosion. The de-painting process is essential to ensure the quality of aircraft exterior paints. However, because the Korean Air-Force's de-painting process is currently done with sanding or Plastic Media Blasting (PMB) method, it is exposed to harmful dust and harmful compounds and consumes a lot of manpower. This study compares the de-painting process currently applied by the ROK Air-Force and the more improved process of the US Air Force, and performs economic analysis for the introduction of advanced equipment. It aims to provide information that can determine the optimal time to introduce new facilities through Cost-Volume-Profit (CVP) analysis. As a result of the analysis, it was confirmed that the sanding method had the most economical efficiency up to 2 units per year, the PMB method from 3 to 21 units, and the laser method from 22 units or more. In addition, in a situation where the amount of de-painting work is expected to increase significantly due to the increase in fighters in future, BEP analysis was conducted on the expansion of the existing PMB method and the introduction of a new laser method. As a result of the analysis, it was confirmed that it is more economical to introduce the laser method when the amount of work exceeds the PMB work capacity(18 units per year). The paper would helpful to improve the productivity and quality of the Korean Air Force Aircraft maintenance depot through timely changes of facilities in the workplace in preparation for expansion.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.4
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• pp.95-108
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• 2007

Test application of revegetation measure was made on the roadside slope damaged by Nongseo-Eomo national road improvement project in a bid to prevent the soil from being washed out as well as to restore the ecological environment, and the survey for assessment of the effect of slope revegetation measures was conducted, beginning May 11 through Nov 7, 2006. In the wake of comprehensive reviewing and evaluating the surrounding topographic environment, physical and chemical characteristics of soil, germination of revegetation plants, analysis of bio mass, covering ratio and the plants appeared, measure b was found to have been most appropriate to cut blasting rock slope, and alternatively measure c. For cut ripping rock slope, measure c-1 appeared to be effective in revegetation effect, and alternatively, b-1.When it comes to cut soil slope, measure c-2 was found to be effective, and b-2 to be a good alternative. And for embankment soil slope, measure b-3 appeared to be most efficient in revegetation effect and measure f as alternative.