• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.288-293
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• 2007

To evaluate effects of airborne microorganisms in fresh cut processing plant, microorganisms in air, equipments, raw material, water and final product were isolated and identified using Vitek (R)2 compact system. Airborne microorganisms were isolated from 1000L air using air sampler for floating microorganisms and plate count agar for falling microorganisms. And contaminated microorganisms of equipment, water, and product were isolated from plate count agar plate. Total plate counts for floating and falling, raw material, equipments and final product were $10^2-10^3CFU/m^3,{\sim}10^1CFU/plate,\;10^3CFU/g,{\sim}10^4CFU/cm^2\;and\;10^4CFU/g$, respectively. From the result of isolated microorganism identification from raw material to final product, airborne microorganisms could affect the flora of final product.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.2
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• pp.109-123
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• 2020

Objectives: The aims of this study were to review the standards and key components of the standards for disposable masks in Korea, the US, EU, Japan, and China and to evaluate the appropriateness of disposable masks during a virus pandemic. Methods: We reviewed the standards in the above countries and compared their key elements for each standard. For the second purpose, systemic paper gathering using key words like 'mask', 'respirator' 'virus', and 'coronavirus' in the PubMed search engine was performed. Fifty-three papers were selected and reviewed in regard to the appropriateness of test protocols with sodium chloride(NaCl) particles for virus filtration and the effectiveness against viruses. Results: The standards for masks are largely divided into two categories: US standards and EU standards. In Korea, the Ministry of Employment and Labor adapted the EU standards for workers and the Health Masks adopted the Ministry of Employment and Labor standards by the Ministry of Food and Drug Safety. Regarding airborne viral infections, WHO emphasizes only droplet infection, while many studies have shown that small particles enter the air through coughing or sneezing, which increases the possibility of airborne infection. Compared to other particles, various factors such as airborne viability and the ability to replicate the virus in the body are further involved in the virus's airborne infection rate. Airborne infection is classified into absolute air infection, preferential air infection, and opportunistic air infection. The NaCl-certified N95 mask showed good filtration efficiency against viruses and NaCl particles were proved to be a surrogate material for viruses. From this, KF94 is also expected to be effective in blocking viruses. Conclusion: The N95 test method could be used as a surrogate test method for virus filtration. N95-class masks have been found to effectively block viral infections in the air. However, surgical or medical masks are only partially effective against airborne virus infection though they could effectively block large droplet infection. However, most studies considered in this study targeted N95 in foreign countries and studies on masks actually used in Korea are very limited, so studies on microorganisms and reuse on domestic masks should be conducted in the future.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.1
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• pp.70-76
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• 2017

Objectives: This on-site study was performed to evaluate the reduction efficiency of an air cleaner on particulate matters and biological agents in a swine facility. Materials and Methods: Particulate matter was measured using a real-time monitoring recorder and biological agents were sampled with a one-stage impactor and then analyzed based on the microbial culture method. An experimental process for the reduction effect on airborne pollutants through air cleaner operation consisted of three conditions: no treatment, wet scrapper by water spray and wet scrapper by disinfectant spray. Results: Geometric mean levels of particulate matter(TSP, $PM_{10}$, $PM_{2.5}$ and $PM_1$) were presented at $1,608{\mu}g/m^3$, $1,373.8{\mu}g/m^3$, $401.8{\mu}g/m^3$ and $144.5{\mu}g/m^3$ for no treatment; $1,503{\mu}g/m^3$, $1,017{\mu}g/m^3$, $159.4{\mu}g/m^3$ and $69.8{\mu}g/m^3$ for wet scrapper by water spray; and $1,222.17{\mu}g/m^3$, $477.17{\mu}g/m^3$, $33.2{\mu}g/m^3$ and $11.1{\mu}g/m^3$ for wet scrapper by disinfectant spray, respectively. In the case of biological agents, the geometric averaged concentrations of total airborne bacteria and fungi were as follows: $45,371cfu/m^3$ and $13,474cfu/m^3$ for no treatment, $43,286cfu/m^3$ and $8,610cfu/m^3$ for wet scrapper by water spray, and $2,440cfu/m^3$ and 1,867 cfu/ for wet scrapper by disinfectant spray, respectively. Regardless of particulate matter and biological agent, the highest concentrations were found for no treatment, while the lowest concentrations were found with wet scrapper by disinfectant spray. Conclusions: Based on the results obtained from this on-site evaluation, there was a significant reduction effect on particulate matter and biological agents through the application of an air cleaner in this study.

• Journal of Environmental Health Sciences
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• v.26 no.3
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• pp.32-37
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• 2000

Nowadays, a new word called SBS(sick building syndrome) has been come into existence. At the point of time when an interest about indoor air pollution and, according to this, countermeasure plan are internationally. Moreover institutional countermeasure should be attended at national level since indoor air quality in public places where many people gather is directly connected with national health. Especially indoor pollution of indoor stadia where all sorts of sports are held can give rise to every kinds of respiratory ailments to players as well as audiences. So it is presented as a main factor that indoor space of stadia is crowded with players and audiences compared with other kinds of indoor space. Therefore, in this research to analyze pollution degree of indoor circumstance for gymnasium and exercising room of folk wrestling. basketball, judo, wrestling, hapkido, swordsmanship and boxing making indoor gymnasium and exercising room an object, when 7 items were measures such as thermocircumstance(temperature, relative humidity, air current, intensity of illumination), dust, carbon monoxide, and carbon dioxide being based on the indoor environmental standard of the first clause of Article 45 of public utilization service which is showed at public hygiene of the Ministry of Health and Social Affairs, it was showed that indoor temperature, relative humidity, air current and intensity of illumination were over standard amount at the most of folk wrestling gymnasium and exercising room. Indoor density of carbon monoxide was preserved to the extent of standard amount (10ppm) at all gymnasiums but carbon dioxide was not in excess of standard amount(1,000 ppm) at most of gymnasiums. Indoor density of dust induced from respiration exceeded the standard amount (150 $\mu\textrm{g}$/㎥) at all gymnasiums of the folk wrestling. Since the folk wrestling players and participants feel physical subjective symptom seriously, in other words the degree of indoor air pollution at gymnasiums and exercising rooms of the folk wrestling is very high, fundamental solution and countermeasure plan should be presented.

• Journal of Korean society of Dental Hygiene
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• v.9 no.3
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• pp.282-293
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• 2009

The purpose of this study was to examine the degree of infection control implemented at dental offices and factors affecting it in an attempt to help promote the health of dental health care workers. The subjects in this study were 180 medical personnels who worked at dental offices in the region of South Jeolla Province. A self-administered survey was conducted from April 1 to May 30, 2008, and the collected data were analyzed. The findings of the study were as follows: 1. As for the implementation of infection control at the dental offices, what the health care workers investigated did the most was post-treatment hand washing(95.0), a constant separation of infectious wastes(94.4), wearing rubber gloves all the time during medical instrument cleansing(92.8) and pre-treatment hand washing(91.7). 2. In regard to the implementation of infection control at the dental offices, what the dental personnels did the least was drying their hands with air(5.0), wearing goggles in times of treatment(23.3), receiving regular education on infection control(26.7) and putting sterilizers to a performance test on a regular basis(43.9). 3. The dental health care workers were significantly different according to age in the management of contagious diseases(p=0.005). Their career made a significant difference to the management of contagious diseases(p=0.000) and instrument cleansing/sterilization(p=0.043). The service area made a significant difference to wearing and managing personal protective clothes (p=0.040) and waste management(p=0.040). 4. Concerning the relationship between the acquisition of dental hygienist certificate and the practice of infection control, whether the dental health care workers were certified or not made no significant difference to that. 5. As to the correlation among the factors affecting the prevention and management of contagious diseases, there was a positive correlation among hand washing(r=0.379), wearing and managing personal protective clothes(r=0.349), instrument cleansing/sterilization(r=0.323) and waste management(r=0.388). All the factors made a statistically significant difference to the prevention and management of contagious diseases(p<0.01).

• Textile Coloration and Finishing
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• v.14 no.6
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• pp.313-318
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• 2002

Chitosan is known to be an excellent biocompatible natural polymer. Recently, with a growing interest of health and environment, chitosan which is good in no harmful effect on human body and environment, has been watched as the finish treatment of hygiene and pleasantness. The purpose of this study is to develop multi functional fabrics by chitosan added on acrylic acid grafted cotton fabrics. Therefore physical properties such as moisture regain, air permeability, whiteness, static voltage and tensile strength of chitosan added on acrylic acid grafted cotton fabrics were investigated. The results are as follows ; According to increased chitosan's concentration, grafting yield was decreased. Therefore thickness of film by treated chitosan added on acrylic acid grafted cotton fabric became thin. FT R spectra of chitosan add on acrylic acid grafted cotton fabric clearly showed peaks of COOH and $NH_2$, Moisture regain, static voltage of chitosan add on acrylic acid grafted cotton fabrics were increased than control. Air permeability, whiteness and tensile strength were decreased than control.

• Safety and Health at Work
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• v.10 no.3
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• pp.389-392
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• 2019

When conducting an exposure assessment, the primary goal of the industrial hygienist is to fully characterize the worker's exposure during a work shift to compare it with an occupational exposure limit. This applies regardless of the duration of the work activity as an activity that is relatively short in duration can still present exposure in excess of the occupational exposure limit even when normalized over an 8-hr shift. This goal, however, is often impeded by the specification of a minimum sample volume in the published sampling method, which may prevent the sample from being collected or submitted for analysis. Removing the specification of minimum sample volume (or adjusting it from a requirement to a recommendation), in contrast, allows for a broader assessment of jobs that consist of short-duration and high-exposure activities and also eliminates the unnecessary practice of running sampling pumps in clean air to collect a specified, minimum volume.

• Korean journal of aerospace and environmental medicine
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• v.30 no.3
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• pp.91-94
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• 2020

The coronavirus infectious disease-19 (COVID-19) pandemic has had a profound impact on the aviation industry. In order to overcome this crisis, airlines have made their efforts in various fields. Therefore, we tried to summarize these efforts of airlines. It is also essential to keep aircraft that have been in landing for a long time in optimal condition. In this paper, we tried to find out about efforts to maintain landing aircraft and maintenance of personnel. Through such constant care, airlines will be able to quickly respond to increasing aviation demand when the infectious disease situation is stabilized in the future. Finally, airlines and passengers must make several efforts to ensure that passengers are free from COVID-19 while traveling by air. These include general precautions to prevent infection, separation of airline personnel and passengers, changes in seat assignments and in-flight services, periodic aircraft disinfection, and prevention of in-flight infections.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.20 no.4
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• pp.274-281
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• 2010

The objectives of this study are (a) to investigate the distribution patterns and exposure concentrations of biological agents in sawmill industries and (b) to compare sampling methods of biological agents. The representative processes of 5 sawmills were selected to measure total airborne bacteria, fungi, endotoxin as well as dust. Airborne bacteria and fungi were measured with one stage impactor, six stage impactor and gelatin filteration methods. Endotoxin was collected with polycarbonate filters and analysed by kinetic chromogenic Limulus Amebocyte Lysate method. Geometric mean levels of airborne bacteria, fungi, endotoxin and dust were 1,864 CFU/$m^3$, 2,252 CFU/$m^3$, 31.5 EU/$m^3$ and 2.4 mg/$m^3$. The ratios of indoor/outdoor concentrations were 3.7 for bacteria, 4.1 for fungi, 3.3 for endotoxin and 9.7 for dust. The respiratory fractions of bacteria were 68.0, 50.9, 49.2 and 45.1% in band-saw, table-saw, rip-saw process and outdoor air. The respiratory fractions of fungi were 78.7, 90.8, 87.5 and 84.8% in band-saw, table-saw, rip-saw process and outdoor air, respectively. There was no significant differences in bacterial concentrations among single stage, six stage impaction and filteration methods. But, fungal concentrations measured with filtration methods were significantly higher than those with impaction methods. Geometric mean levels of airborne bacteria and fungi were higher than the OSHA guideline values of 1,000 CFU/$m^3$. The respiratory fractions of fungi were above 75%. The concentrations of biological agents were significantly different among culture-based sampling methods. In the exposure assessments of biological agents, further studies are needed for the comparisons of diverse sampling methods and the investigations of environmental factors.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.4
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• pp.465-471
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• 2015

Objectives: An objective of this study is to apply a thermal image camera which shows various color according to temperature of indoor surface for estimating concentration of airborne fungi. Materials and Methods: While wall temperature were monitored by applying the thermal image camera, airborne bacteria as well as air temperature and relative humidity have been measured in lecture room and toilet of university for seven months. Results: Based on the results obtained from this study, the ranges of temperature and airborne fungi concentration were $20{\sim}24^{\circ}C$ and $20{\sim}400cfu/m^3 $ for red image, $17.5{\sim}20^{\circ}C$ and $35{\sim}150cfu/m^3$ for orange image, $15.5{\sim}17.5^{\circ}C$ and $25{\sim}650cfu/m^3$ for sky-blue image, and $13.5{\sim}15.5^{\circ}C$ and $50{\sim}200cfu/m^3$ for blue image, respectively. The color of indoor surface taken shot by thermal image camera showed consistent trend with temperature of indoor surface. There is, however, little correlation between color of indoor surface and airborne fungi concentration(p>0.05). Among environmental factors, relative humidity in indoor air showed a significant relationship with airborne fungi concentration(p<0.05). Conclusions: The more measurement data for proving statistically an association between color of indoor surface and airborne fungi concentration should be provided to easily estimate indoor level of airborne fungi.