The levels of Indoor radon can increase in newly built apartments that mainly use construction materials such as concrete. However, radon measurement in newly built buildings has only been implemented recently, and there is a lack of sufficient data for radon management purposes. This study aimed to determine the levels of indoor radon in newly built apartments by regions, sizes of household, and floor (lower, middle, upper floor), and to explore the trend of radon reduction by time according to ventilation methods. Indoor radon was measured in 48 households in four regions (Gyeonggi-do and Gangwon-do). Measurements were performed for 48 hours and 24 hours under closed and ventilated conditions using real-time measurement devices FRD400 and RAD7, respectively. To analyze changes in radon concentration by floors, data were collected by dividing households into lower, middle, and upper floors according to their vertical height. The concentrations of indoor radon ranged from 12.1 Bq/m3 to 559.0 Bq/m3 when windows were closed and 12.0 Bq/m3~500.0 Bq/m3 when ventilated (including both mechanical and natural ventilation). On average, the concentration of closed conditions of household when sealed (arithmetic average 185.3 Bq/m3) was 1.5 times higher than the concentration during ventilation (including mechanical and natural ventilation: 123.8 Bq/m3), and around three times higher than the average for mechanical ventilation (65.7 Bq/m3). It was found that the indoor radon concentration statistically increased as the height increased and the size of the house became smaller. Typically, it took 7 to 8 hours to exceed the standard of 148 Bq/m3 after windows were closed. It decreased to less than 148 Bq/m3 within 3 to 4 hours after operating the mechanical ventilation system. However, in the case of natural ventilation, it takes more than 24 hours to reach below the standard value, and the concentrations stagnated after 24 hours. In conclusion, radon concentration in narrow spaces can be relatively high if ventilation is not sufficient due to the nature of apartments with wall-type structures. Therefore, it is necessary to prepare various radon reduction measures according to floor, size, and ventilation methods.

최근 발생되는 재난의 추이를 살펴보면 기후변화에 따른 자연재해 발생빈도가 증가하고 있으며, 이에 따른 피해 규모 추세가 대형화로 변화되고 있다. 대규모로 진행되고 있는 도시화와 고도의 산업화로 인해 도시개발 지역의 확대와 중첩 영향으로 대형 자연 재난이 발생하여 도시시설물에 직접적인 손실이 발생하고 있다. 옥외광고물의 무분별한 설치로 도시의 미관훼손은 몰론 강풍으로 인 한 파손 및 추락 등의 사고가 빈번히 발생하는 실정이다. 이러한 피해는 강풍에 취약한 옥외광고물의 내풍설계 기준의 미비가 가장 큰 요인으로 인식되는데 풍하중 반영한 옥외광고물 설치는 전문지식이 필요한 분야로 중소규모의 옥외광고사업자가 대부분인 국내 현실 과는 괴리가 발생하고 있다. 따라서 본 연구에서는 전국에서 이용할 수 있는 풍하중을 안전성 관점에서 산정하였고, 이를 바탕으로 옥 외광고물 설치 고정자재 수 등을 산정할 수 있는 내풍표준 가이드라인을 제시하였다.

As modern society has emerged and developed, the subway has established itself as a representative means of transportation in the city due to its speed, accuracy, and accessibility. According to the Indoor Air Quality Management Act, underground stations have established and managed the maintenance and recommendation standards for PM10, PM2.5, CO2, CO, HCHO, NO2, Rn, VOCs However, th the standards for airborne mold has not been applied for subway stations even though management for the health effect of exposure to mold is necessay. In this study, the correlation with major contributing factors was analyzed by measuring the concentration of airborne molds in the indoor air of underground stations and through literature research. It was confirmed that there was a correlation between the concentration of airborne molds in subway stations and the major contributing factors. As a result of the analysis, it was found that the concentration of airborne molds became higher as the location of the platform became deeper underground, during periods of congestion, and especially in summer. There was no significant correlation with the year of construction. Our findings indicate that appropriate management measures should be devised in response to such contributing factors.

We investigated the distributions of airborne radon concentration on the platforms of the stations of Seoul Metro by the underground depth of each subway line, and explored the correlation between the radon concentration and the depth and geological conditions around each underground station. The measurements of radon levels were performed in 254 subway stations within Seoul Metro Lines 1 to 8 using the passive sampler (RADUET). Radon concentration data from 2007 to 2017, as well as the depth of each subway station were obtained from the Seoul Metro corporation. The geological information of each subway station were purchased from the Korea Institute of Geoscience and Mineral Resources. Student t-test and correlation analyses were performed to compare the levels of radon by the depth of subway stations, and to investigate the association of radon levels based on geological information. The geometric mean concentration of the all subway stations was 27.9 Bq/m3 ( range, 3 . 7Bq/ m3~124.0 Bq/m3). The depth of Lines 5-8 (geometric mean, –20.3 m) was significantly deeper by about 50% or more than that of Lines 1-4 (–13.1 m) (P<0.01). The radon levels increased significantly in deeper depths and as the number of Lines increased (P<0.05). A significant higher mean concentration of radon above the igneous rock (33.0 Bq/m3) was observed, comparing to that of non-igneous rock (27.5 Bq/m3) (P<0.00001). Our findings indicate that the deeper the subway is built or the more it is constructed on the granite area, the more careful management, including frequent ventilation and measurement monitoring, is necessary.

Many people have often reused their disposable respirator multiple times due to reasons of economy and purchasing inconvenience. However, multiple use of a disposable respirator may lead to an adverse effect of its protection performance. In this study, we aimed to determine changes in the protection performance of disposable respirators related to multiple use and to suggest the appropriate number of times of use. The masks of the brands T and Y were selected in this study, respectively. A mask of each brand was used for testing at the same time and place for two hours per day. The protection performance of each disposable mask was tested after consecutive use on days two, three, and four. The protection performance tests for each used mask following wear on a mannequin were performed in the laboratory using GRIMM’s fine dust monitoring device and TSI’s nebulizer. The concentration of PM10, PM2.5, and PM1.0 inside and outside the mask was measured. The filtration rate was calculated and the results were analyzed using the SAS statistical program. The protection rates of the brandnew masks of T and Y brands (blank test) were 80% and 60%, respectively. After one-day usage, the protection rates of the brand-new T and Y branded masks significantly decreased from 80% to 60% and from 60% to 50%, respectively. Rather, the slight drops of protection rate were observed after two or more days of respirator use. Our findings indicate that the change of protection performance could occur after one-time use. It would not be recommended to use disposable respirators several times in terms of in terms of protecting human health from environmental hazards.

As indoor activities continue to increase, the importance of indoor air is emphasized. Moreover, children's activities are emphasized as being vulnerable. In this study, vocal organic compounds (VOCs) and CO2 in the indoor air were analyzed among children aged 4 to 7 years attending day care centers in Seoul. In the case of VOCs, the average concentration measured during a period of 24 hours in an asthmatic home was 143.9 (μg/m3). The average concentration measured during a period of 24 hours in the asthma and rhinitis home was 146.7 (μg/m3). In CO2, the average concentration measured during a period of 24 hours in the asthmatic home was 665.9 (ppm). The average concentration measured during a period of 24 hours in the asthma and rhinitis home was 695.9 (ppm). In this study, asthma symptoms increased as the concentration of indoor pollutants increased. Exposure of VOCs (μg/ m3) and CO2 (ppm) among environmental factors shows that respiratory symptoms such as asthma can be induced.

Mold grows more easily when humidity is higher in indoor spaces, and as such is found more often on wetted areas in housing such as walls, toilets, kitchens, and poorly managed spaces. However, there have been few studies that have specifically assessed the level of mold in the indoor spaces of water-damaged housing in the Republic of Korea. We investigated the levels of airborne mold according to the characteristics of water damage types and explored the correlation between the distribution of mold genera and the characteristics of households. Samplings were performed from January 2016 to June 2018 in 97 housing units with water leakage or condensation, or a history of flooding, and in 61 general housing units in the metropolitan and Busan area, respectively. Airborne mold was collected on MEA (Malt extract agar) at flow rate of 100 L/min for 1 min. After collection, the samples were incubated at 25oC for 120 hours. The cultured samples were counted and corrected using a positive hole conversion table. The samples were then analyzed by single colony culture, DNA extraction, gene amplification, and sequencing. By type of housing, concentrations of airborne mold were highest in flooded housing, followed by water-leaked or highly condensed housings, and then general housing. In more than 50% of water-damaged housing, the level of airborne mold exceeded the guideline of Korea's Ministry of Environment (500 CFU/m3). Of particular concern was the fact that the I/O ratio of water-damaged housing was greater than 1, which could indicate that mold damage may occur indoors. The distribution patterns of the fungal species were as follows: Penicillium spp., Cladosporium spp. (14%), Aspergillus spp. (13%) and Alternaria spp. (3%), but significant differences of their levels in indoor spaces were not found. Our findings indicate that high levels of mold damage were found in housing with water damage, and Aspergillus flavus and Penicillium brevicompactum were more dominant in housing with high water activity. Comprehensive management of flooded or water-damaged housing is necessary to reduce fungal exposure.

The aim of this study was to examine indoor fungal concentration and fungal volatile organic compounds(VOCs) in single-person households. A total of 22 houses occupied by one person were investigated in this study. 19 VOCs detected in the field were estimated as fungi-derived VOCs through a review of the literature, and 11 VOCs were confirmed as fungal VOCs by laboratory experiments. Exposure to fungal VOCs in the indoor environment has been confirmed to be highly influenced by airborne fungal concentration and indoor humidity. 3-octanone was characterized by a clear generation profile in Aspergilus versiocolor, and n-decane in Pencillum chrysogenum. ntetradecane emitted by Stachybotrys chartarum exhibited a tendency to occur consistently. The observations made in this study demonstrated that single-person households can easily be exposed to fungi, and MVOCs can be used as an indicator of fungal exposure in indoor environments.

Exposure to the indoor air pollutants could be associated with the risk of developing atopic dermatitis, including allergic symptoms and exacerbations. A total of Fifty homes who had a past or current symptoms of atopic dermatitis were enrolled in the study. To rate the levels of environmental factor, we measured concentrations of PM2.5, PM10, Heavy metals XRF (X-Ray Fluorescene), Bacteria (CFU/m3), mold (CFU/m3) in dust of the children’s houses. The prevalence of atopic dermatitis in children is increasing especially in Urban areas. Exposure to levels of indoor environmental factor and air pollutants has been related to atopic dermatitis development. The house dust were higher for the results of atopy, asthma patients analyzed fungi and bacteria, resulting XRF measurements Cr (chromium), As (arsenic), Br (bromine), Cd (cadmium), Hg (mercury), Pb (lead) etc. this has a significant relationship. Recent studies have shown that indoor air pollutants control is beneficial in reducing atopic dermatitis prevalence and development. Urban areas children are exposed to kinds of indoor environmental factor and air pollutants that may lead to atopic dermatitis development.

An up-flow botanical bioreactor was proposed as an economical and environmentally-friendly control process to remove the odorants, specifically ammonia and hydrogen sulfide, in exhaust gas. Liriope Platyphylla and Hedera Helix were selected as the test plants, and were put into the lab-scale reactor filled with the ceramic media. During 52 days of operation with ammonia loading of 1.16 g/m3·d, Liriope Platyphylla showed better performance in ammonia removal. Liriope Platyphylla was further tested by the simultaneous loading of 6.96 g/m3·d for ammonia and 1.00 g/m3·d for hydrogen sulfide. Microbial activity in the botanical reactor was greatly enhanced by mixed odorants rather than single odorants, and can contribute to removing odor in the exhaust gas. Biological uptake by plants reached up to 20% of total nitrogen loading to the botanical reactor.

The concern of fine particle (PM2.5) management of outdoor environments has been increasing due to its exposure and related health effects in Korea. As a result, PM2.5 standard in atmosphere environment was regulated in 2015. On the other hand, indoor PM2.5 standard has been required because most people spent their times in indoor environments. In this study, we measured the PM2.5 and PM10 concentrations both indoor and outdoor environments of public-use facilities such as underground stations, underground shopping centers, and nurseries for 24 hour with filter-weighing method in Seoul and Daegu. Measurement duration was from March to April in 2014 during the Asian dust period. At all measurements, indoor to outdoor (I/O) concentration ratios exceeded 1 except 1 day nursery in Daegu in spite of Asian dust period. The ratios of PM2.5 to PM10 concentrations ranged from 0.63 to 0.75 in indoor environments, and from 0.63 to 0.82 in outdoor, indicating that PM2.5 should be carefully managed in indoor environments as well as outdoor atmosphere.

본 연구는 2013년 순천만국제정원박람회가 폐막한 시점에 박람회를 관람한 이용객들을 대상으로 한 의식조사 결과를 토대로 향후 대응방안을 모색하는데 목적이 있다. 설문조사는 2013순천만국제정원박람회를 방문한 방문객을 대상으로 5~10월에 이루어졌으며 총 690부를 현장에서 배포하여 회수하였다. 수집된 설문지 가운데 유효설문지 627부를 SPSS, EXCEL Program 등을 활용하여 분석하였다. 그 결과, 2013순천만국제정원박람회는 전체적으로 긍정적인 평가를 하고 있는 것으로 나타났다. 긍정적으로 평가한 점으로는 400만명 관람객 유치, 생태경관자원의 활용대안 제시, 창조경제의 새로운 모델제시, 순천시의 브랜드 가치 향상, 시민들의 자긍심 고취, 정원관련산업에 대한 기대 효과 등을 들 수 있다. 아쉬운 점으로는 정원관련 콘텐츠 부족, 정원관련산업분야 참여 미흡, 초기 운영미숙, 편의시설 부족, 기념품·지역특산품 부족 등을 들 수 있었다. 또한, 박람회장의 사후 활용방안에 대해서는 국제적인 생태 및 정원관련 테마파크, 창조형 문화예술 복합단지 등으로 활용하는 것이 바람직하다고 판단하고 있었다. 박람회 개최의 가장 기본적인 취지와 목표는 생태 및 정원문화의 보급에 있다고 전제한다면 우선적으로 순천시민을 비롯하여 전남도민에게 생태·정원문화를 보급하고 이를 적극적으로 확산시킬 필요가 있다. 또한, 생태·정원 연관산업 활성화를 위한 연구기관, 기업, 학회, 관련 단체 및 전문가로 구성된 정원문화산업 클러스터를 구축하고 연중 이벤트 개최 및 대규모 회의를 유치하여 박람회장을 적극 활용하면서 지역민들의 지속적 관심을 유도하며 국내 제1호 국가정원을 추진함으로서 안정적 운영 및 관리체계를 구축, 그리고 정원문화 확산 및 정원 연관산업 육성을 위한 정책개발 및 제도 도입이 요구된다.

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.