The fluidized bed has been used generally for Industrial process such as chemical reaction process, separation process, incineration and etc. It is very efficient for such application because of equitable contact of each fluidized element with fluid passing through it and maximizing active contact area to adsorb and react from the fluid. This study had focus on application of fluidized bed for air purifier as household appliance and analyzed its performance in comparison to typical fixed media type. As a result, fluidized bed performed in this study had higher removal efficiency for acetaldehyde over two times within initial operation term and had lower pressure drop over 0.7mmAq than that of fixed media type.

In this study, we attempted to estimate the association between asthma oriented by indoor air sources and personal exposure by comparing the case (asthma-patient) and control (non-asthma-patient) groups. We selected 27 participants who showed positive response on lung function and methacholin provocation test. We performed environmental survey with 15 and 10 cases during May and June 2007, respectively. There was no significant difference between the case and control groups in the level of formaldehyde and TBC (Total Bacterial Count). In the dust allergen test, the case concentration was higher than the control's, without signifiant difference. In the personal exposure assessment of VOCs using OVM (Organic Vapor Monitor) badge, the case concentrations of Benzene, Toluene, and Ethylbenzene were higher than the control's, but there was no significant difference. The personal exposure of Xylene case study was significantly higher than the control's

In this study, the performance of fast gas chromatography system was evaluated using VOC standards prepared in both liquid and gaseous phase. When the liquid‐phase VOC standards were analyzed by both direct injection and HS‐SPME method, all the chromatographic separation was completed within 4 minutes. The calibration experiments were conducted further using gaseous standard of BTX. The calibration results derived by direct injection method generally showed good linearities, regardless of phases, while it was not the case for HS‐SPME method. In case of liquid‐phase standard, MDL values for direct injection and HSSPME method were calculated in the range of 0.07~0.19 to 0.63~3.76 ng, respectively. In contrast, MDL values for gaseous standard were 0.27~0.45 and 1.94~6.90, respectively. The reproducibility of our method, when expressed in terms RSE, showed above 5 %. When the sensitivity of different techniques is compared, the calibration slope values of BTX decreased on the order: direct injection of liquid‐phase standard > HSSPME method of liquid‐phase standard > direct injection of gaseous standard > HS‐SPME method of gaseous standard. Although fast GC is very efficient to reduce the total running time significantly, extended studies are desirable to improve its reproducibility.

Absenteeism is an important index that is related not only to health but also to direct daily activities. It may lead to a student's poor educational performance and overall reduction in educational quality. Particularly, diseases causing school absenteeism are important for environmental health of children's study. However only a few studies regarding the effects of air pollution on school absenteeism due to respiratory disease have been reported. This study was performed to examine the effect of air pollution on absenteeism by respiratory disease, using school attendance reports from March 2002 to December 2004. In this study, we counted absenteeism numbers using school absenteeism data from the first to sixth grade and classified absenteeism into illness-related, non-illness-related and respiratory disease-related illness absences. To this end, we used air pollution data (CO, NO2, PM10, and SO2) and temperature and relative humidity data collected during the study period. Daily counts of absenteeism were analyzed by Generalized Additive Model after the adjustment of several factors such as seasonal variation, day of the week, and meteorological parameter confounders in a nonparametric approach. For each air pollutant, we analyzed illness-related absences, non-illness-related absences, and respiratory- illness related absences. Then, we considered both influenza and non-influenza related absenteeism type. In illness-related absences analysis, absenteeism risks increased to 1.05(1.02-1.08) for CO and 1.06 (1.02-1.10) for NO2 by each interquartile range change with adjustment for influenza. The risks for respiratory-related absences of CO and NO2 increased to 1.05(1.02-1.08) and 1.04(1.01-1.08), respectively by each interquartile range change with adjustment for influenza. However, in the analysis of non-illness-related absences, there were no significant risks for the effect of all air pollution. This result shows that air pollution can affect respiratory-related absences and provides a basis for developing environmental health policy against air pollution.

In recent semiconductor manufacturing clean rooms, air washers are used to remove airborne gaseous contaminants such as NH3, SOx and organic gases from outdoor air introduced into clean room. In order to improve the gas removal performance of the air washers, a hot water contact heat exchanger can be installed upstream of an air washer, heating and humidifying the incoming outdoor air before entering the air washer. In the present study, an experiment was carried out to examine closely the improvement of gas removal efficiency by the insertion of the hot water contact heat exchanger. The experiment showed that the gas removal efficiency was increased by the water vapor condensation effect.

This study aims to present the fundamental strategies for improving the Indoor Air Quality ( IAQ ) in newly unoccupied apartment units. The results of this study can be summarized as follows, The field survey of 160 newly unoccupied units with airtight doors and windows showed that the concentrations of HCHO and TVOC were higher than the standards. The emission rates of HCHO and TVOC were proportional to the height. The small chamber test of pollutant concentration for building materials showed that pollutants were emitted dominantly from the wood furnishings and adhesives.