The objective of this study is to support an environmental policy related to the improved control of indoor airborne fungi in Korea. We reviewed 15 articles published in Korea to analyse the trend of airborne fungi level in indoor environment of various public facilities. The maximum mean concentrations of total airborne fungi in hospital and kindergarten were 1447 CFU/m3 and 1259 CFU/m3, respectively. We concluded that policy determination are urgently required to guide a proper management on airborne fungi in Korea.

This study investigated viability variation of airborne bacteria in indoor environments. The survival in air as a temporal function of bioaerosol viability was reported for Escherichia coli (KCCM 12119, ATCC 11775). Bacteria suspended in distilled water were aerosolized and entered the vertical duct oriented downward. After measurement of number concentration and colony forming unit (CFU) of the bacteria at different locations of the duct, the viability function was calculated. It was found that the bacteria viability(%) decreased with time after aerosolization, 28.454e^-0.132x (x:time, min). This study demonstrated the potential application of viability function of airborne bacteria to studies of exposure assessment and infection risk analysis.

The objective of this study is to quantify the levels of airborne bacteria in pig building according to pig housing type. Mean concentration of airborne bacteria in the housing room of gestation/farrowing pigs were 3,690(±1,528)cfu m^-3 in spring, 10,145(±4,266)cfu m^-3 in summer, 1,546(±835)cfu m^-3 in autumn, and 2,582(±916)cfu m^-3 in winter, respectively. Mean concentrations of airborne bacteria in the housing room of nursery pigs were 11,628(±5,624)cfu m^-3 in spring, 36,054(±13,260)cfu m^-3 in summer, 2,743(±1,688)cfu m^-3 in autumn, and 4,075(±2,300)cfu m^-3 in winter, respectively. Mean concentrations of airborne bacteria in the housing room of growing/fattening pigs were 34,025(±8,652)cfu m^-3 in spring, 36,619(±10,234)cfu m^-3 in summer, 10,230(±3,521)cfu m^-3 in autumn, and 26,208(±5,248)cfu m^-3 in winter, respectively. As a result, mean concentrations of airborne bacteria in terms of pig housing type were highest in growing/fattening housing room followed by nursery housing room and gestation/farrowing housing room (p<0.05). The pig building showed the highest levels of airborne bacteria in summer followed by spring, winter and autumn (p>0.05). Overall airborne bacteria which have particle size over 2.1㎛ (stage 1~stage 4) accounted for approximately 80% compared to total airborne bacteria regardless of pig housing type. The predominant airborne bacteria in pig building were Micrococcus spp., Brevibacillus spp. and G(+) Bacillus.

To evaluate the indoor air quality of food manufacturing plants, the presence of viable bacteria and fungi was assessed in the indoor air of the facilities at which 9 food items were manufactured. Air samples were collected from the general zone, low clean zone and clean zone of each factory with an air sampler, in combination with plate counts agar using for bacteria, and dichloran-glycerol agar for fungi. The samples were incubated at 25℃for 4 to 7 days. After culture, the colony forming units (CFU) on each plate were counted and corrected with a positive hole conversion table. The average concentration of bacteria was 2.2 × 10³ CFU/㎥ in the general zone, 1.2 ×10³ CFU/㎥ in the low clean zone and 7.3 × 10² CFU/㎥ in the clean zone. The average concentration of fungal microbes was 2.5 × 10³ CFU/㎥ in the general zone, 2.6 × 10³ CFU/㎥ in the low clean zone, and 2.0 × 10² CFU/㎥in the clean zone. No meaningful differences were detected between the general zone and the low clean zone, but the clean zone had significantly lower concentrations than the other zones. Additionally, the identification of the fungi was performed according to morphological method using a giant culture and slide culture. The fungi were identified as belonging to 18 genera, and the genera Cladosporium(33%), Penicillium(29%) and Aspergillus(26%), predominated. Aspergillus isolates were identified to species level, and A. ochraceus, a mycotoxigenic species, was identified. As part of the effort to control the quality of the indoor air of food manufacturing plants, our results show that continued studies are clearly warranted.

High-throughput microscopy (HTM) was developed recently for the automatic detection of airborne asbestos fibers that can cause lung cancer, asbestosis and mesothelioma. The HTM method has been applied to couting the airborne asbestos fibers as an alternative to the conventional phase contrast microscopy (PCM). In this paper, we demonstrated that the HTM enabled us to obtain quantitative results for low-concentration airborne asbestos samples under detection limit, and we made a comparison between the results from HTM and PCM. In addition, a verification study was conducted using proficiency analytical testing (PAT) samples of chrysotile and amosite. The HTM method can be applied to the existing PCM method by reducing analysis time and labors. Potential applications can be extended to detection of asbestos fibers in soil and water.

The aim of this study was to compare the concentrations of airborne pollutants (i.e., PMs, TVOC, and ozone) released from a laser printer with a new and/or a refilled toner cartridge. Also we compared the concentrations before and after attaching a HEPA filter at the outlet of exhausted air for each printer. PMs, TVOC, and ozone were released from all three different branded printers with both toner cartridges in accordance with their both a brand new and a used condition. For PMs, there were generally significant differences of concentrations between a brand new and used toner (p<0.05). Ozone level differences were found between a new and a refilled toner, but were not significant (p>0.05). For TVOC, there were significant differences of concentrations among brands, and toluene (3.46mg/m³) only was identified. The overall 70% of reduction for PMs’concentrations occurred after attaching a HEPA filter(p<0.05), and these results were pronounced for TSP. These results showed that similar levels of airborne pollutants were released from a laser printer with a new and a refilled toner cartridge. Also, these results indicate that the usage of a HEPA filter may be an effective method for reducing the released pollutants from a laser printer.

본 연구의 목적은 공기감염성 가축질병 유발의 주요 인자인 부유 세균 및 바이러스 등의 생물학상 인자들에 대한 유형별 공기청정기의 제균 효과를 비교 평가하는 데 있다. 시료 채취 장비에 대한 포집 성능 평가에서는 MS2 바이러스와 Pseudomonas fluorescens 모두 Button sampler보다는 Biosampler에 의한 채취 효율이 유의하게 높았다 (p<0.05). 공기청정기 유형 및 시료채취 방법에 관계없이 MS2 바이러스의 경우 초기 농도 대비 가동 후 5분에 50% 이상, 15분에 70% 이상, 30분에 80% 이상, 그리고 마지막 측정 시점인 60분에는 90% 이상의 제거 효율을 보이는 것으로 나타났다. P. fluorescens 세균의 경우 초기 농도 대비 가동 후 5분에 45% 이상, 15분에 50% 이상, 30분에 70% 이상, 그리고 마지막 측정 시점인 60분에는 75% 이상의 제거 효율을 보이는 것으로 나타났다. 유형별 공기청정기의 상대적 제균 효율을 비교해 보면 MS2 바이러스의 경우 이온 발생 방식>전기 집진 방식>습식 방식>건조 방식, P. fluorescens 세균의 경우 전기 집진 방식>이온 발생 방식>건조 방식>습식 방식의 순서로 조사되었다.

The objective of this study is to assess a level of microbial contamination in the KTX. Investigation sites in the KTX were cabin, gateway, toilet and passenger seat. It was found that the mean concentrations of airborne bacteria and fungi were 157 CFU/m³ and 84 CFU/m³ , respectively, in all of the investigation sites of the KTX. They did not exceed the domestic standard (800 CFU/m³ ) for airborne bacteria and the guideline (150 CFU/m³ ) for airborne fungi recommended by WHO. Mean levels of bacteria and fungi distributed in passenger seat were 2.6×10⁵ cfu/m³ and 3.7×104 cfu/m³ , respectively. The predominant genera identified in the KTX were Bacillus, Corynebacterium, Staphylococcus and Micrococcus for bacteria and Aspergillus, Cladosporium and Penicillium for fungi, respectively. Based on identification result, the profiles of airborne bacteria and fungi in the KTX was wholly similar to those of bacteria and fungi distributed in the passenger seat.

2008년 동아시아 대륙에서 발생기원이 다른 먼지(황사)와 인위적 오염입자의 광역적 이동 사례를 NOAA위성 RGB 합성영상과 지상 입경별 분진(TSP, PM10, PM2.5)의 질량농도 관측으로 분석하였다. 또한 Terra/Aqua 위성 MODIS(Moderate resolution Imaging Spectroradiometer) 센서의 AOD(Aerosol Optical Depth)와 FW(Fine aerosol Weighting)를 통해 동아시아 지역에서 발생기원이 다른 대기 에어로졸의 분포와 입자 크기 특성을 분석하였다. 중국 북부와 몽골, 그리고 중국 황토고원에서 모래폭풍이 발생하여 광역적으로 이동하여 청원에 먼지입자(황사)로 영향을 주는 6 개의 사례분석을 실시하였다. 질량농도 TSP중 PM10은 70%, PM2.5는 16%로 조대입자(〉 2.5 μm)의 비율이 큰 것은 사막과 반사막의 자연적 발생원에서 생성되었기 때문이다. 그러나, 모래 폭풍이 이동 과정에서 중국 동부의 산업 지역을 거쳐 유입하는 사례에서는 TSP 중 PM2.5가 23%까지 증가하기도 했다. 중국 동부로부터 황해를 거쳐 한반도로 유입한 5개 다른 사례의 경우, TSP 중 PM10, PM2.5가 각각 82, 65%로 나타났다. 이와 같이 PM2.5의 상대적 비율이 증가한 것은 인위적 오염입자의 영향 때문이다. 동아시아 지역에서 인위적 오염입자의 광역적 이동 사례에 대한 평균 AOD는 0.42±0.17로 황사에 의한 AOD(0.36±0.13)와 비교하여 대기 에어로졸에 대한 비율이 높게 나타났다. 특히, 중국 동부에서 황해, 한반도, 동해에 이르는 광역적 지역에 AOD값이 높게 분포했다. 인위적 오염입자의 사례는 FW가 평균 0.63±0.16로 모래폭풍의 이동 사례의 0.52±0.13 보다 높은 값을 보였다. 이는 대기 에어로졸에 대한 인위적 미세 오염 입자의 기여도가 클 수 있음을 제시하고 있다.

In this paper the lifetime risk assessment of exposure to airborne volatile organic compounds (VOCs) in environmental atmosphere was carried out in one of the Korean industrial city, Gumi based on their measurements of VOCs at five representative outdoor monitoring sites. According to this study toluene, trichloroethylene, and dichloromethane are three main VOCs in Gumi. The carcinogenic risks 5the carcinogenic VOC are greater than the benchmark concentration (1.0E-6) in all five designated sites. Particularly, the Lifetime Cancer Risk in industrial complex 1 and 2 reached 9.64E-5 and 1.32E-4, respectively, both of which are far higher than the benchmark risks. The components of predominant risk in industrial areas are found as chloroform, benzene and trichloroethylene, while those of other sites are benzene and chloroform. It was estimated that the contributions of those componentsto cancer risk are not less than 90%. For non carcinogenic VOCs, the total hazard indices in 5 monitored sites are less than 1. The hazard index in industry complex No. 2 recorded the highest among 5 sites up to 0.663 due to the dominant contribution of 1, 2-dichloropropane by up to 50% (0.335). Based on this analysis, effective emission reduction for chloroform, benzene, trichloroethylene, and 1,2-dichloropropane will rapidly I the cancer risks and hazard indices in Gumi.

In order to improve indoor air quality of apartment, indoor ventilation system had to be installed in each unit, from 2006 in Korea. However, a duct which is connecting each room in ventilation system became a flanking path of sound. Sound which is generated in one room can easily transmitted into the adjacent room by the duct and speech privacy in apartment room can be seriously degraded. In this study, low noise duct system consisted of noise diffuser and multi drop chamber was developed and noise reduction performance was measured in mock-up system. Noise reduction performance of low noise duct system was compared with conventional duct system. From the result of measurement, it was found that noise diffuser reduce more than 10 dB in the range of 200 Hz and higher frequency band, also multi drop chamber was effective in 2000 HZ and higher frequency band. Noise reduction performance of low noise duct system is effective in the frequency range (from 300 Hz to 4000 Hz bands) of speech conversation.

The aims of this study are to examine the concentration and identification of airborne organism at exhibit hall and storage in museums and to provide fundamental data to protect cultural assests from damage. This study surveyed the concentration of airborne bacteria and fungi at exhibit hall and storage in museums located 4 metropolitans from July to October, 2007 and literature data on airborne microbes of museums in Korea that were publiced in relevant Korean journals. The concentrations of airborne bacteria and fungi were higher than those in storage. Pseudomonas spp. and Bacillus spp for bacteria and Aspergillus spp. and Penicillium spp. for fungi were shown mainly in museums. Pooled average concentration of airborne bacteria in museums was 34.2±10.1 CFU/m³ for exhibit hall and 17.2±10.0 CFU/m³ for storage, respectively. Pooled average concentration of airborne fungi in museum was 26.0±11.2 CFU/m³ for exhibit hall and 16.6±11.0 CFU/m³ for storage, respectively.

2005년 1월부터 12월까지 지속적으로 몽골과 중국 북부의 사막과 건조지대에서 모래폭풍의 발생, 이동 그리고 한국에서 먼지침전(황사)을 모니터링하였다. NOAA 위성의 AVHRR(Advanced Very High Resolution Radiometer) 관측 자료를 직접 수신하여 false colour 합성영상을 만들어 모래폭풍의 발생과 이동 사례를 중점 분석하였다. 또한 모래폭풍 발원지의 풍하측에 위치한 한국 중부의 청원에서 PM10 농도가 190μg m-3 이상인 황사 사례에 대한 PM10, PM2.5농도와 시정 그리고 O3, NO2, CO, SO2 농도의 변동을 분석하였다. 2005년에는 발원지에 적설과 강력한 고기압, 저기압의 이동이 미흡하여 강한 모래폭풍의 발생이 적었고 한국에서도 황사의 발생 빈도가 1997-2005년의 평균과 비교하여 적었다. 한국에는 2005년 총 7회, 11일간의 황사 사례가 발생하였다. 여름에는 발원지가 습하고 바람이 약해 모래폭풍의 발생이 적었으며, 한국에서도 황사의 발생이 없었다. 발원지에서 발생한 모래폭풍이 중국의 대도시와 산업지대를 거치지 않고 한국으로 직접 이동할 경우, 먼지침전에 따른 PM2.5 농도는 PM10 농도의 20% 이하였다. 그러나 모래폭풍이 중국 동부의 산업지역을 거쳐 한국으로 이동할 경우 인위적 대기오염 물질이 함께 유입되어 PM2.5 농도가 증가하여 PM10농도의 25%이상을 나타내었다. 또한 2005년에는 사막에서 날아온 모래 먼지의 PM10농도가 190μg m-3 이하여서 황사로는 미흡한 5개 이상 사례를 관측 및 분석하였다.

After infection by Gram negative bacteria, neonatal patients or patients in intensive care unit usually suffer from endotoxin shock, leading to death finally in spite of eradication of bacteria by potent antibiotics. The purpose of this study that is the pilot study to prevent endotoxin shock and nosocomial infection, is to offer basic data on species and concentrations of airborne microbes in hospitals. Therefore, this study collected and analyzed articles and documents on airborne microbes in hospitals in Korea that were published in relevant journals from 1980 to 2004. Studies on the concentration of airborne microbes in hospitals as a part of study on the nosocomial infection have been performed from the latter half of 1970s. Pooled average concentrations of total suspended bacteria in hospitals by RCS air sampler and Cascade air sampler were 194.85 CFU/㎥ and 367.72 CFU/㎥, respectively. They were lower than the guideline concentration(800 CFU/ ㎥) of the Korean Ministry of Environment. Pooled average concentrations of total suspended fungi in hospitals by RCS air sampler and Cascade air sampler were 20.66 CFU/㎥ and 193.34 CFU/㎥, respectively. They were lower than the guideline concentration(150 CFU/㎥) of the World Health Organization(WHO). Pooled average concentrations of total suspended bacteria in operating room and intensive care unit(ICU) were 324.75 CFU/㎥ and 182.43 CFU/㎥, respectively. They again were lower than the guideline concentration of the Korean Ministry of Environment. Staphylococcus spp., Micrococcus spp., and Lactobacillus spp. for Gram-positive bacteria, and Pseudomonas spp., Klebsiella spp., and Escherichia spp., for Gram-negative bacteria were shown in hospitals. Also, Aspergillus spp., Penicillium spp., Mucor spp., Epidemophyton spp., Trichophyton spp., and Cladosporium spp. for fungi were found in hospitals. Staphylococcus spp. was shown frequently in operating rooms, intensive care units and wards. Penicillium spp. and Aspergillus spp. were shown commonly in them.

The PC game rooms in Korea have a problem in the aspect of indoor air quality because there are many occupants for 24 hours where the smoking is allowed. This study was carried out to evaluate indoor air quality (IAQ) including the size distribution of respirable suspended particulates (RSP) and airborne nicotine concentration in selected PC game rooms. The subjects are 6 PC game rooms in Seoul and Sung-Nam Cities. In this study, airborne RSP and nicotine concentrations were measured during a period from February to March, 2003. Significant correlation has been found between the concentrations of RSP and nicotine in PC game room. Also the negative correlation was found between room area and number of operating fan. The correlation coefficients between RSP size distribution and nicotine concentration were 0.868, 0.866, 0.870 in the stages 2 (cut-point 14.80㎛), 5 (cut-point 3.50㎛), and 8 (cut-point 0.52㎛) from Marple's 8-stage cascade impactor, respectively. In conclusion, RSP concentration in PC game room has a tendency to increase by smoking. Therefore, it is suggested that the effective air control system and education program be applied for PC game room.

PM (Particulate Matter) samples contained fungal spores were collected in the ambient air of Seosan, west Korea, in springtime of 2000 and 2001. PM concentrations were 199.8μg m-3 in the 1st Asian Dust Storm period (March, 23 ~ 24) and 249.4μ

In full-speed cruising, the airborne sound pressure levels are measured from 11 small fishing boats operated around Cheju Island. In these measurement, 9 measuring positions are selected in each fishing boats. The results of measurements and analyses are as follows: 1. The sound pressure levels in FRP boats are higher than those in wooden boats. 2. The highest sound pressure level is 112dB(A) at the engine room in C boat, while the lowest one is 72dB(A) at the front deck in K boat. 3. The highest sound pressure level is shown to be in the frequency band less than 500Hz. 4. The highest sound pressure level is shown to be in the frequency band less than 500Hz. 5. Through all 9 positions, the sound pressure levels are higher in B and C boat and lower in E and K boats.