• Journal of Environmental Health Sciences
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• v.35 no.5
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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.

• Land and Housing Review
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• v.12 no.2
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• pp.91-97
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• 2021

High levels of fine dust is an increasing health concern in major cities such as Seoul. To improve the indoor air quality of apartments, this study examined the ability of an air shower system installed in an apartment unit to remove fine dust (as defined by ISO 12103-A2) from various clothing items of building occupants entering their apartment. Results of the experiment indicate that an air shower system is effective in removing final dust from clothing after one pass through the system. The fine dust removal efficiency for various clothing items was 74% for a dress suit, 70.6% for hiking clothes, 63.3% for knit-wear, 50.5% for a cotton t-shirt, and 38.8% for a coat. Fine dust removal efficiency increased with a second and third pass through the air shower system by an average of 9.1 and 13.9 percentage points respectively compared to a single pass through the system.

• Korean Journal of Human Ecology
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• v.22 no.6
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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.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.11
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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.

• Journal of the Korean Society of Radiology
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• v.14 no.3
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• pp.313-318
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• 2020

Since radon is an inert gas and is a monoatomic molecule, the size of one particle represents the size of an atom, which means that it has a radius of approximately 1 to 100 nm. Therefore, if the mask has a radius smaller than the size of general fine dust and ultra fine dust, but it is possible to block the inhalation of radon more than a certain amount, it is considered that the exposure through the inhalation of radon can be reduced through normal indoor wear. Accordingly, we would like to find out the radon blocking effect of a mask worn in everyday life. Looking at the reduction rate of radon for each mask, cotton masks decreased by 33.45%, medical masks by 33.50%, KF 80 masks by 35.12%, and KF 94 masks by 37.72%. It was found that the radon blocking effect of the cotton and medical masks was somewhat inferior to that of the KF mask, but the difference was not so great that the introduction of radon into the air could be blocked to a certain level by wearing a mask.

• Journal of Technologic Dentistry
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• v.33 no.1
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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.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.6
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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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• v.14 no.10
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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.

• Fire Science and Engineering
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• v.19 no.2 s.58
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• pp.63-68
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• 2005

In this study, the arc dispersion properties were analyzed according to switching of high sensitive type Residual Current Protective Device(RCD) contacts. Arc dispersion and ignition process was taken by high speed imaging system(HSIS). In this experiment, electric lamps(60 W) and heaters(950 W) were connected in parallel as loads. In case of normal RCD, it took about 2.3(ms) from the generation of arc to the extinction of uc. When arc was dispersed in normal RCD, it did not ignite cotton. Whereas, in case of RCD deteriorated by NaCl solution, the range of arc dispersion was wider and the arc lasted for 3.3[ms] more compared to normal RCD. And the arc ignited cotton. In order to prevent accidents caused by RCD, we should be careful of environmental factors, such as dust and humidity, and the parts of RCD should be used as incombustible materials.

• 보존과학연구
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• s.6
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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.