식물의 흡수를 통한 공기오염물질 제거는 생육 상태에 따라 그 효과가 달라진다. 실내에서 토양수분의 공급은 식물의 생 육을 위한 기본적인 관리 사항이다. 따라서 본 연구는 토양수 분함량에 따른 생리적 반응이 가스상 공기오염물질인 톨루엔 저감에 미치는 영향을 구명하고, 최적의 생육과 공기 정화 효 과를 위한 적정 토양수분함량을 찾고자 수행하였다. 이를 위 해 스파티필름과 파키라를 사용하여 40일 동안의 평균 토양 수분함량을 25%, 20%, 15%, 10%로 처리한 후 양자수율, 광 합성률, 기공전도도, 증산량 등 생리적 지수와 엽면적당 톨루 엔 저감량을 측정하였다. 그 결과 스파티필름은 토양수분함량 을 20~25%로 관리할 때 생육이 양호하고 최적의 톨루엔 저 감 효과를 얻을 수 있을 것으로 판단되며, 10% 이하 건조에 대한 주의가 요구된다. 반면 파키라는 토양수분함량 20% 이 하 처리구에서 톨루엔 저감량이 증가하였으나 10% 처리구에 서 생장량이 저하될 가능성이 있으므로, 공기 정화와 생육을 위한 최적 토양수분함량은 15~20% 범위이며, 25% 이상으로 장기간 유지하는 것은 과습을 유발할 가능성이 있는 것으로 판단된다.
The indoor air quality of residences has been regulated by designating recommended standard levels of pollutants for newly built apartments. But as of yet, no related guideline has been established for dwellings that are already occupied. From a sociological viewpoint, the gap between the rich and poor has been gradually increasing with economic development, and this has extended to the diversification of house types and living environments. Specifically, people who have the lowest income levels may live in temporary houses such as vinyl greenhouses and shanty houses, and their living environment is mostly inadequate as a result. In this study, we surveyed the indoor air quality in normal and socially vulnerable houses after the occupation stage and tried to figure out the main factors influencing indoor air quality. Airborne fungi are detected more frequently in lower living standard houses. Put another way, the concentration of airborne bacteria and the volatile organic compound levels are much higher than in normal dwellings.
We estimated decreasing rate of indoor air pollutants with are airborne bacteria, airborne fungi, formaldehyde, total volatile organic compounds, PM10, and PM2.5 in 10 children’s hospitals and 6 childbirth houses located in Seoul and Gyeonggi-do from November to December in 2012. Sectional period was respectively divided for operating and non-operating the air cleaners. There was a trend that concentration of surveyed pollutants in children’s hospitals and childbirth houses during operating period decreased among indoor air. We used Monte-Calro simulation to remove uncertainty and identify efficiency of eliminated pollutants such as surveyed pollutants by the air cleaners. Average efficiency of removal were 61.39 ± 21.42% for airborne bacteria, 71.77 ± 19.65% for airborne fungi, 73.37 ± 24.62% for formaldehyde, 71.20 ± 25.96% for total volatile organic compounds, 65.16 ± 23.80% for PM10, and 71.06 ± 23.97% for PM2.5.
Information on time spent in microenvironments has a critical role in individuals’ exposure assessment. Time-activity studies have become an integral part of comprehensive exposure assessment and personal exposure modeling. The aims of this study were to estimate the exposure level of NO2, PM10 and VOCs, and to compare the estimated exposure by using time-activity pattern and indoor air concentration. This study was performed upon 28 university students living in Daegu. We measured air pollutants of NO2, PM10 and VOCs at houses where the university students spent most their times. In this study, according to the summer and winter, time-activity patterns of university students were different. The 28 university students average spending times in house indoors and other indoors time were 11.52±2.14 and 7.63±2.65 hours in summer, and 14.78±3.30 and 6.59±3.03 hours in winter, respectively. The university students personal exposure NO2 concentrations were average 21.62±5.88 ppb and I/O ratio was 0.89±0.27. Personal average exposure of PM10 concentration was between house indoors and outdoors concentrations which indoor house concentration was 37.68±7.57 μg/m3 and outdoor house concentration was 43.85±9.80 μg/m3 with 0.88±0.17 of I/O ratio. Personal exposure to benzene and the average concentration of benzene did not exceed in atmosphere environmental standard (annual 1.5 ppb) and the outdoor houses concentration was much higher than indoor houses.
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.
Indoor air quality can be affected by indoor sources, ventilation, decay and outdoor levels. Although technologies exist to measure these factors, direct measurements are often difficult. Toluene and nitrogen dioxide (NO2) concentrations of residential indoor and outdoor were simultaneously measured and compared in 16 houses, using passive samplers during every 3 days for 60 days. Concentrations of toluene and NO2 were analyzed by gas chromatography and spectrophotometer, respectively. Using a mass balance model, penetration factor (ventilation rate divided by sum of ventilation rate and deposition constant) and source generation factor (source generation rate divided by sum of ventilation rate and deposition constant) were calculated by multiple indoor and outdoor measurements. The mean contributions of toluene of indoor and outdoor sources on residential indoor air quality were estimated to be 31.01% and 67.00%, respectively. On the other hand, mean contributions of NO2 were 58.93% and 41.06%, respectively. These results could be explained that contributions of indoor and outdoor air pollutants sources are different to residential indoor air concentrations. In conclusion, contributions of outdoor air and indoor sources affecting indoor air quality were effectively characterized using multiple indoor and outdoor measurements.
This study was surveyed to evaluate and recognize the distribution characteristics of indoor air pollutants(IAPs) such as the total volatile organic compounds(VOCs), formaldehyde(HCHO), PM10, carbon dioxide(CO2), nitrogen dioxide(NO2), ozone(O3) and radon in 10 elementary schools located in urban, rural, and industrial complex area from November 2005 to February 2006. The average concentration of IAPs were 117.9㎍/㎥ as in PM10, 1,971ppm as in CO2, 486.6㎍/㎥ as in TVOC. These chemical's concentration was exceeded the indoor air standards of the Department of Education in Korea. The indoor concentrations of ozone and toluene was lower than that of outdoor and other pollutants showed the opposite tendency. In schools located industrial complex area, the outdoor concentration of TVOC was higher than that of urban and rural area. Based on the results above, PM10, CO2, TVOC have to be in the order of priority to improve the indoor environment in school. Also it should be performed in the detailed survey considered by the seasonal variation because this study showed cross-sectional results.
Burning mosquito coils in indoor environments maygenerate smoke that can control mosquito effectively. This practice has been used in numerous households in Korea. However the smoke may contain air pollutants of health concern. We conducted the present study to characterize the emission from two common brands of mosquito coils from Vietnam and Malaysia, respectively. We measured mass emission of air pollutants of nitrogen oxides (NOx), fine particulate(PM2.5), formaldehyde (HCHO), total volatile organic compounds (TVOCs), carbon monoxide (CO) and carbon dioxide (CO2) in completely closed chamber. Air pollutants concentrations resulting from burning mosquito coils could substantially exceed health-based air quality standards orguidelines. Under the same condition, air pollutants were measured by cigarette smoking to compare mosquito coil. Burning one mosquito coil would release the same amount of PM2.5 mass as burning 20~58 cigarettes. The emission of HCHO from burning one coil can be as high as that released from burning 27 cigarettes.
This study was to investigate distribution characteristics for air pollutants and to assess probability of health effect for children in kindergartens from August, 2006 to January, 2007. The mean concentrations for standards of maintenance in kindergartens were 91.5 ㎍/㎥ for PM10, 1,185 ppm for CO2, 69.3㎍/㎥ for formaldehyde, 174 CFU/㎥ for TBC and 0.41 ppm for CO, respectively. For NO2, Rn, TVOC, and O3, the mean concentrations in kindergartens were 29.40 ppb, 1.51 pCi/ℓ, 257.3 ㎍/㎥, and 3.74 ppb, respectively. The I/O ratio of every air pollutants exceeded "1" except for O3. In results of calculated safety factor to assess probability of health effect for children by air pollutants in kindergartens, safety factor for CO2 was 1.2 for fixed point. It means that children have probability of health effect caused by CO2. In cases of Monte-Carlo analysis, safety factor for PM10 was 1.0 and safety factor for CO2 was 1.2.
This study was carried out to evaluate the characteristics of volatile organic compounds (VOCs) and aldehydes emission as a function of airtight time in new apartment. Sampling was undertaken at 34 new apartments located in 4 different cities of Korea from February to November 2005. The measurement data were collected every one hour from 10 a.m. to 6 p.m. toward increasing airtight time in a day. The concentrations of VOCs and aldehydes were analysed by GC/MS and HPLC method, respectively. These methods showed good sensitivity, linearity, and repeatability. In this study, the most abundant compounds at new apartments appeared to be toluene, m,p-xylene, formaldehyde and acetone. Moreover, the concentration variations at a closed rooms progressively increased by airtight time of 5 hours. Airtight time of new apartment was a most important and affective factor which influenced concentration change.
This study was performed to investigate indoor air quality and to characterize the concentration of particulate matters followed by human activities in preschool classrooms. Concentrations of PM10, PM2.5, and PM1 were measured every 5-minute intervals by means of a dust monitor adopting the principle of light scattering. Two mini-volume air samplers were used further to measure the I/O concentration ratio of PM10 and to calibrate the dust monitor since the photometric method often exaggerates the mass of fine particles. The calibration factor in the study environment was determined as 0.64. In the preschool classrooms, the ranges of average indoor PM10, PM2.5, and PM1 concentrations were 51.5~117.6, 21.5~98.4, and 16.2~84.5 ㎍/ ㎥, respectively, while that of I/O concentration ratio was 0.8~1.3. Based on correlation analysis among various environmental parameters, PM1 was slightly correlated with humidity (r=0.416, p<0.01). However, outdoor PM10 was strongly related with indoor PM2.5 (r=0.95, p<0.01), with PM1 (r=0.94, p<0.01), and with PM10 (r=0.84, p<0.01). The trend of PM2.5 and PM1 concentrations appeared to be very similar unlike the case of PM10. Since the elevated coarse particle concentration (2.5㎛<dp<10㎛) and the average PM2.5/PM10 ratio were highly dependent on classroom activities, the parameter of PM2.5/PM10 ratio was intensively studied with 7 different indoor activities in the preschool classrooms.
This study performed and re-analysed the articles of exposure assessment for the indoor environment of houses in many environment-related journals published. in Korea since 1990. Based on this comparative study, we estimated the unit health risk on indoor environment. The objective of this study was to offer scientific data for decision-making policy for improvement and management of indoor air quality on Korean house in. The pooled concentrations for the critical air pollutants in the house were 13.93±13.91㎍/m3 (PM10), 680±226 ppm for (CO2), 1.9±1.6 ppm (CO), 419±158 CFU/m3 (bacteria), 0.036 ± 0.002 ppm (NO2), and 104.935 ± 16.424 Bq/m3 (Rn), The pooled concentrations for the volatile organic compounds were 6.9±6.7㎍ /m3 (benzene), 39.3±55.1㎍/m3 (toluene), 4.2±4.0㎍/m3 (ethylbenzene), 11.4±8.3㎍/m3 (m, p-xylene), 4.2 ±1.5㎍/m3 (styrene) and 6.3±4.5㎍/m3 (o-xylene). The unit cancer risk for men and women by inhalation of benzene was 3.7 × 10-5 and 4.8 × 10-6, respectively. In additio
In this study, the paint, which has very close relationship to the of indoor air quality, was examined for the air pollution leveling test, and using the various passive sampler, the test was evaluated on the regard of TWA(Time Weighted Average). This study is to examine how the air pollution levels differ between the regular paint that is used for public and the new developed environment friendly paint. The consecutive experiments were performed in the small chamber test to investigate the VOCs and formaldehyde, ammonia emissions and characteristics from paint which are commonly used as the complete material of building. In conclustion, the natural paint showed the highest emission of VOCs among the selected paints, and water paint showed the highest contents of ammonia. Formaldehyde showed N.D(Not Detected) in most of tests and found a small amount in vinyl paint however, it was not as bad as to fail the certify level of building materials. It is recommended to constantly develop the chamber system and it will be very much possible to be used for the estimation of indoor air pollutants from the various paints and other complete materials.
The work of hairdressers includes washing, coloring, bleaching, permanent waving, conditioning, and cutting scalp hair. Hairdressers are subjected to a number of physical and toxicological hazards. The toxicological hazards are those resulting from exposure to a wide range of chemicals and from chemicals are usually classified active processes. In this study, twenty beauty shops were selected to assess the exposure to indoor air pollutants such as VOCs and particulate matter (PM10) during one month from September 1 to September 30, 2003. Indoor air quality of beauty shops might be worse by vehicle emissions because the beauty shops were generally located near roadway. Personal exposures to VOCs and PM10 were related to indoor concentrations of beauty shops, respectively. According to questionnaire, hairdressers responded sore throat, eye irritation, and nervousness as health effect symptoms. Conclusively, users as well as workers in beauty shop might be highly exposed to air pollutants from indoor sources and outdoor sources. Therefore, proper methods should be prepared to improve the indoor air quality in beauty shop.
Currently, Ministry of Environment has promulgated and executed 'the legislation of indoor air quality for public facilities' but the data of indoor air pollutant for public facilities of this law was very insufficient. Therefore, collection of data for indoor air pollutants and execution for risk assessment in order to offer scientific data for decision-making of policy to present reasonable standards and preventive techniques of engineering were required. Therefore, this study collected and re-analysed the articles of exposure assessment for indoor environment in journals related environment in Korea since 1990 and estimated the safety factor on residents in public facilities. The objective of this study was to offer scientific data for decision-making of policy for improvement and management of indoor air quality in Korea. As the results of this study, the risk assessment for the critical pollutants in CTE (central tendency exposure) showed that safety factors according to pollutants were less than 1 which means safe level in micro-environments. It was investigated that the safety factors of CO in hospital, NO2 in terminal, PM10 and NO2 in subway station respectively were over than 1 in RME (reasonable maximum exposure). Through the results, it was investigated that health risk by inhalation of criteria and guideline air pollutants in domestic public facilities was not high. It should be considered effect of inhalation by other hazardous air pollutants because this study was examined just partial pollutants. Presentation of scientific data for expansion of study is requisite and active research of health risk assessment about indoor air quality.
Studies evaluating the health effects of hazardous air pollutants assume that people's exposure to typical pollutant level is the same as specific regional pollutant level. However, depending on social and demographic factors, time-activity pattern of people can vary widely. Since most people live in indoor environments over 88% of the day, evaluating exposure to hazardous air pollutants is hard to characterize. Objective of this study was to estimate the exposure levels of university students of NO2, VOCs(BTEX) and PM10 using the scenarios with time-activity pattern and indoor concentrations. Using data from time-use survey of National Statistical Office in 2009, we investigated time-activity pattern of university students and hourly major action. A total of 1,057 university students on weekday and 640 on weekend spent their times at indoor house 13.04 hr(54.32%), other indoors 7.70 hr(32.06%), and transportation 2.36 hr(9.83%). Indoor environments in which university students spent their times were mainly house and school. Air pollutants concentrations of other indoor environments except house and school such as bar, internet cafe and billiard hall were higher than outdoors, indicating that indoor to outdoor ratios were above 1. According to three types of exposure scenarios, exposure to air pollutants could be reduced by going home after school.
In this study, we investigated PM10, NO2, and 1-hydroxypyrene(1-OHP) in urine at indoor environments which are 35 houses and 20 hospitals for using air cleaner and non-using air cleaner in Seoul metropolitan area and Kyoung-gi province from April, 2003 to February, 2004. Moreover, we examined effect of improvement for indoor air quality and health effect by concentration of 1-OHP also we investigated removal efficiency by air cleaner for PM10, NO2, and 1-OHP that were 28.5%, 27.4%, and 42.1% respectively. Concentration of PM10, NO2, and 1-OHP were 19.02±18.14㎍/m3, 8.66±3.06ppb, and 0.19±0.18㎍/g creatinine when air cleaner was no worked. The concentration for PM10, NO2, and 1-OHP were 13.60±10.79㎍/m3, 6.29±2.71ppb, and 0.11±0.10㎍/g creatinine, respectively. It was significant statistically. Therefore, it is considered using the air cleaner to remove the partial pollutants in indoor environment and is positive effect for health.
The oil crisis of the 1970s and the rise in oil prices motivated people to implement energy conservation strategies. Buildings were fitted with additional insulation and reduced ventilation rates. The reduction of mechanical and natural ventilation rate led to increases in indoor pollutant concentrations which resulted in increased health risks from indoor exposure to pollutants. The variable-air-volume/bypass filtration system(VAV/BPFS) is a variation of the conventional VAV systems, The VAV/BPFS is an electronically controlled system that provides cost-effective thermal comfort and acceptable indoor air quality. Under controlled conditions in a chamber, a series experiments were performed to compare the ability of a VAV/BPFS to remove indoor aerosol concentration and to reduce energy consumption with that ability of conventional VAV system. Results show that the VAV/BPFS increases the effective ventilation rate and removes indoor air pollutant, and maintains acceptable indoor air quality without sacrificing energy consumption.