• 한국환경보건학회지
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• 제35권5호
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• pp.386-392
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• 2009

This study was undertaken to compare the performance of three dust samplers for collecting cotton dust fibers. For this study, three dust samplers including Vertical Elutriator (VE), Total Dust Method (TDM) using 37 mm cassette, and the Institute of Occupational Medicine (IOM) sampler were selected. A total of 6 cotton mills and 4 towel factories were investigated. When measured by VE, the GM for cotton dust was 0.19 $mg/m^3$ which was less than the current occupational exposure limit (OEL) 0.2 $mg/m^3$. But when measured by TDM and IOM at the same locations, the GMs were 0.37 and 0.63 $mg/m^3$, respectively. In Korea, most industrial hygienists have used the TDM for cotton dust measurements and the results were compared with either the TLV for cotton dust or the PNOC (particulates not otherwise classified) of 10 $mg/m^3$ for making decisions. The results of this study clearly showed that past cotton dust measurements and decisions made with such results were not correct. It needs to be noticed the related contents by using VE if it applies to the exposure limit, 0.2 $mg/m^3$, and needs to be revised the exposure limit by IOM. Also, if TDM is used, it requires to be studied and suggested to the new OEL.

• 토지주택연구
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• 제12권2호
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• pp.91-97
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• 2021

본 연구는 에어샤워 시스템의 가동에 따른 5종의 의류(Dress Suit, Hiking Clothes, Knit, Cotton T-Shirt, Coat)의 미세먼지의 제거성능을 파악하고자 한 것으로 그 연구결과를 요약하면 다음과 같다. 첫째, 에어샤워 시스템 가동 실험결과, 미세먼지 제거율은 1회 가동시에만 평균 59.4%가 제거 되고 있었다. 특히, 2회 및 3회 가동시에는 68.5%에서 최고 73.3% 까지 제거율을 나타내고 있었다. 둘째, 5종류의 의류종류별 제거율은 Dress Suit 74.0% > Hiking Clothes 70.6% > Knit 63.3% > Cotton T-Shirt 50.5% > Coat 38.8% 순으로 나타났다. 즉, 의류 종류에 따라 코트 등 털 소재의 의류는 정전기 등의 원인으로 미세먼지 제거율이 다른 소재에 비해 적게 나타났지만 보통 의류인 경우는 50% 이상의 제거율을 보이고 있었다.

• 한국생활과학회지
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• 제22권6호
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• pp.687-699
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• 2013

This study was carried out to investigate the antifungal activity and house dust mite repellent effect of cotton and silk fabrics dyed with Juniperus chinensis heartwood extracts by hot-water and methanol. The chemical composition of Juniperus chinensis heartwood extracts by hot-water and methanol was analyzed by GC-MS. In the case of antifungal activity, dyed fabrics with hot water extract had no effect against chaetomium globosum fungus. But showing no growth in fabrics dyed with methanol extract, dyed fabrics with methanol extract showed very excellent antifungal activity. Silk fabric dyed with methanol extract showed excellent house dust mite repellent effect of 94.3%~96.0% against dermatophagodes farinae. The composition of Juniperus chinensis heartwood extracts from hot-water and methanol was different. There were no terpene and its analogue peaks in hot-water extract. However there were terpene and its analogue peaks in methanol extract. From these GC-MS results, terpene was identified in methanol extract of Juniperus chinensis heartwood. Efficient ingredient of antifungal activity and house dust mite repellent effect was assumed terpene.

• 한국기계가공학회지
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• 제20권11호
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• pp.86-91
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• 2021

Recently, functional clothes that can reduce deposition and/or penetration of fine dust have been developed. However, there are no methods to quantitatively evaluate the performance of these clothes. In this study, we developed a method to contaminate a fabric using fine dust and established an approach to quantitatively assess the degree of particle contamination on the fabric surface. Silicate powder was chosen as the particle to simulate fine dust because silicate particles are fluorescent under UV light; therefore, they can be distinguished from any color of non-fluorescent fabric surface. A camera with a high-resolution lens system was used to scan the surface of the contaminated fabric surface, and the degree of particle contamination of the fabric surface was analyzed in terms of the pixels corresponding to the area of the fabric surface contaminated by silicate particles. Finished or unfinished nylon fabrics as well as cotton fabrics were contaminated with silicate particles, and their surfaces were scanned using the established camera. The proposed assessment method was found to be useful for quantitatively comparing the degree of particle contamination of the fabrics.

• 한국방사선학회논문지
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• 제14권3호
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• pp.313-318
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• 2020

라돈은 불활성기체로서 단원자분자이기 때문에 입자 하나의 크기가 원자 하나의 크기를 나타내며 이는 대략 반경 1~100 nm를 가지고 있다는 것을 의미한다. 따라서 마스크가 차단하는 일반적인 미세먼지, 초 미세먼지의 크기보다 작은 반경을 가지지만 일정 이상의 라돈의 흡입을 차단할 수 있다면 평소 실내착용을 통해 라돈의 흡입을 통한 피폭을 줄일 수 있을 것으로 사료된다. 이에 따라 일상생활에서 착용하는 마스크의 라돈 차단 효과를 알아보고자 한다. 각각의 마스크 별 라돈 감소율을 보면 면 마스크가 33.45%, 의료용 마스크가 33.50%, KF80 마스크가 35.12%, KF94 마스크가 37.72% 순으로 감소하였다. 면, 의료용 마스크가 KF 마스크보다 라돈 차단 효과가 다소 떨어지지만 그 차이는 크지 않아 마스크의 착용만으로도 공기 중 라돈의 유입을 일정 수준 차단할 수 있음을 알 수 있었다.

• 대한치과기공학회지
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• 제33권1호
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• pp.93-102
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• 2011

Purpose: The study aimed to evaluate working environment for dental technician by measuring dust level, ventilation conditions and the use of personal protective equipment and to provide basic information required to improve working environment and develop health education programs for dental technician. Methods: A total of 240 dental technician who are registered with the Daegu Association of Dental technician and working at 34 dental laboratories participated in the study. And the dust level was measured at 21 different spots in 16 dental laboratories out of 34. Results: Of 34 dental laboratories, 31 (91.2%) were equipped with a ventilator, but the remaining 3 (8.8%) did not have a ventilator. By the number of ventilator, 1 to 3 ventilators were found in 22 dental laboratories (71.0%), 4 to 6 ventilators were in 7 laboratories (22.5%) and more than 7 ventilators in 2 laboratories(6.5%). According to the frequence of changing filters in dust collector, 20 dental laboratories (58.9%) changed filters every four weeks, 10 laboratories (29.4%) changed them every six weeks and 4 laboratories (11.7%) changed them every eight weeks. Of total respondents, 114 (61.3%) said they wore a mask all the time while working, 56 (29.6%) said they frequently wore a mask, 19 (10.1%) said they did not wear a mask. As for the type of masks, 159 (84.1%) used a disposable mask, 25 (13.2%) used a cotton mask and 5 (2.7%) used an anti-dust mask. For dust sat on their outfits while working, 102 (54.0%) shook their uniforms inside workplace to keep dust off the uniforms, 64 (33.9%) did not anything until they wash their uniforms and 23 (12.1%) shook their uniforms outside workplace to keep dust off the uniforms. Of total respondents, 182 (96.3%) had a particle in their eyes while carrying out grinding work. Based on the measurement of floating dust at workplace, 3 dental laboratories showed dust concentration exceeding the minimum level of 10 mg/$m^3$ allowed under the permit for environment. Of those, 1 laboratory had the dust concentration that was more than 1.5 times higher than the minimum level. Dust concentration was higher in laboratories that used a dust collector with 0.5 horse power and changed filters more than 3 weeks ago. Dust comprised of nickel (more than 70%), chrome (9%) and others. The mean chrome concentration was more than twice higher than the minimum permissible level of 0.5 mg/$m^3$. There were two laboratories that showed chrome concentration exceeding the level of 0.4 mg/$m^3$. Like dust concentration, chrome level was higher in laboratories that used a dust collector with 0.5 horse power and changed filters more than 3 weeks ago. There were six laboratories that had nickel concentration exceeding the minimum permissible level of 1 mg/$m^3$. Of those, one laboratory had nickel concentration that was more than three times higher than the minimum permissible level. Nickel concentration was also higher in laboratories that used a dust collector with 0.5 horse power and changed filters more than 3 weeks ago. Conclusion: It is not likely that heavy metal concentrations found in the study constitute respiratory dust. It is however necessary for health of dental technician to apply the Industrial Safety and Healthy Law to dental laboratories and make recommendations for the use of personal protective equipment, installation of a proper number of ventilators, more frequent change of filters in dust collector and improved ventilation for polishing work. At the same time, dental technician need education on how to use personal protective equipment and how to efficiently remove dust from their uniforms.

• 한국의류학회지
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• 제26권6호
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• pp.811-820
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• 2002

The physical responses and subjective sensations of different cleanroom garments were compared in order to discover which cleanroom garment design could minimize pollution of the working environment by dust from the worker, maintain a pleasant microclimate and provide effective thermoregulation. A. Coverall with non-detachable hood, kimono sleeves (front), raglan sleeves (back), raschell net on the bodice B. Coverall with detachable hood, kimono sleeves (front), raglan sleeves (back), raschell net on the bodice C. Separate top with non-detachable hood, kimono sleeves (front), raglan sleeves (back), raschell net on the bodice D. Coverall with non-detachable hood, set-in sleeves, raschell net on the bodice E. Coverall with non-detachable hood, raglan sleeves (back), l00% cotton inner wear (upper body) The results of the experiment were as follows. Because the hood covered the shoulder and the chest areas, the chests temperature of the worker wearing garment E was quite higher than those wearing other garment designs. For fabric that has been coated in order to prevent dust, layered designs should be avoided in order to prevent skin temperature from rising. Compared with layers of underwear, it would be more effective to attach a see-through raschell net which clings to the body. Thermal sensations were also highest in garment E, reinforcing the finding that layered designs should be avoided. Through the experiment, it was found that a new material coverall with a non-detachable hood was effective in minimizing dust, suppressing skin temperature increases, maintaining a superior microclimate and providing pleasant subjective sensations.

• Asian Pacific Journal of Cancer Prevention
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• 제14권10호
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• pp.5657-5661
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• 2013

In India, among males, leukemia rates vary across the country. The present unmatched hospital-based case-control study conducted at Tata Memorial Hospital included subjects registered between the years 1997-99. There were 246 leukemia cases and 1,383 normal controls. Data on demographics, lifestyle, diet and occupation history were recorded. Cigarette (OR=2.1) and bidi smoking (OR=3.4) showed excess risk for leukemia. Odds ratios were 3.9 for fish-eaters, 0.40 for chilli eaters, 1.5 for milk drinkers and 0.60 for coffee drinkers, compared to non-drinkers/eaters. However, neither exposure to use of pesticides nor cotton dust showed any excess risk for leukemia.

• 한국화재소방학회논문지
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• 제19권2호
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• pp.63-68
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• 2005

본 논문에서는 고감도형 누전차단기의 스위칭에 따른 접점의 아크 비산 특성을 해석하였다. 누전차단기(RCD) 스위칭에 따른 접점의 비산과정 및 인접가연물로의 착화과정은 고속카메라(High Speed Imaging System)를 이용하여 촬영하였다. 부하는 전등부하 60W와 전열부하 950 W를 병렬로 연결하였다. 정상상태의 RCD의 경우 아크의 생성부터 소멸까지의 시간은 약 2.3[ms]을 알 수 있었으며, 아크가 비산될 때 주변에 인접가연물(탈지면)을 착화시키지 못했다. 염수에 의해 오염된 접점의 경우 아크의 비산범위가 훨씬 컸으며 지속시간도 3.3[ms]동안 더 지속되었다. 그리고 주위에 가연성 물질에 착화가 가능하였다. RCD에 의한 사고를 예방하기 위해서는 수분, 먼지 등의 환경적 요인에 주의해야 하며, RCD소자는 난연성 재료를 사용해야 된다.

• 보존과학연구
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• 통권6호
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• pp.96-110
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• 1985

This report is briefly thied to introduce the kinds of clothes for the body of deceased and special features of remains in the era of the middle of Yidynasty found in Changheung IM's tomb, and some remarks related to the conservation treatment for shrouds as well. The contents of this report are summed up as follows:1. Included with the clothes of dead body of IM's clan were 2 pcs. Of woman's jacket, 2 pcs. of underpants, 1pcs. of single layered overcoat twithout cotton, 1pcs.of women's overcoat with a single layered thin cotton inside, women's socks, cushoned mattress, straw shoes and other hemp fabrics etc. By the observation of these remains, it is considered that they dressed the deceased with new cloth taken from the unsuals not prepared specially and stored beforehand for such as occasion as does it nowadays.2. As to the conservation treatment, the materials were comparatively good and so they employed general tank washing method with special neutrality liquid soap(made by Lab, of Household Products, Pacific R & D Center) for cleaning imbrued matrials on the clothes. After cleaning and drying naturally at a shade place, remains put into apaulowania tree box were fumigated by mixed gas (M. B. + E. O.) for prevention of damages from fungi and insects.3. Desirable environment control for scientific conservation of such kinds of cellulose textiles is to be illuminated at below 50Lux, temperature 16-18℃, relative humidity 45-60%($\pm$4%) and removed the dust. For the prevention of the damaging fungi and insects, it is desirable to fumigate by mixed gas (M.B.+E.O.) once a year.