Building materials are composed of very complex chemical compounds. The aims of this paper are to investigate the emission concentrations of indoor pollutants from new apartment house and the emission variation patterns during 75 days. The average value of total volatile organic compounds(TVOCs) concentration was 3,768 ㎍/㎥ in five new apartments. Major VOCs included toluene, ethylbenzene, m,p-xylene and o-xylene. The average concentrations of each compound were measured as : benzene(58㎍/㎥), toluene (793㎍/㎥), ethylbenzene(438㎍/㎥), styrene(79㎍/㎥), m,p-xylene(1,210㎍/㎥), o-xylene(364㎍/㎥). The results indicated that the major VOCs from the new apartment were affected by building products such as on aromatic hydrocarbon compounds. TVOCs emission are characterized as high emission level at initial time (12,856㎍/㎥) and decreased through time. After a lapse of 75 days in sample house, TVOCs concentration decreased in about 20 times as compared with the initial concentration. The TVOCs emission profiles strongly depended on the generation mode and the concentration of the VOCs in building material.

The emission concentrations of VOC and various odorous compounds were measured from different indoor process units located in 19 companies at the Ban Wall industrial complex from Jun. 2004 to Jan. 2005. The purpose of this study was to investigate the indoor pollution levels of various industrial facilities with respect to bothmalodorous compounds and volatile organic compounds (VOC). We also intended to build the database under the conditions affected by various anthropogenic processes with an aid of a statistical treatment. The three samplingmethods and five analytical techniques were applied tomeasure the sum of up to 32 individual compounds. According to this study, we were able to identify the importance ofmajormalodor compounds which include carbonyl compounds, reduced sulfur compounds, ammonia and trimethylamine. On the other hand, relative contribution of VOC as sources ofmalodor was ofminor significance except such compound as toluene. The overall results of this study thus indicate that the concentration levels of VOC in themanufacturing facilities are high enough to affect indoor laboring conditions.

In recent models of semiconductor manufacturing clean rooms, air washers are used to remove airborne gaseous contaminants such as NH3, SOx and organic gases introduced from outdoor air into clean room. Meanwhile, there is a large quantity of exhaust air produced from clean room. It is desirable to recover heat from exhaust air and use it to reheat outdoor air. In the present study, an experiment was conducted to investigate heat recovery, particle collection, and gas removal in a heat recovery type air washer system for semiconductor manufacturing clean rooms.

Bioaerosols are airborne particles of biological origins including viruses, bacteria, fungi, and all varieties of living materials. In suitable hosts, bioaerosols are capable of causing acute or chornic diseases that may be infectious, allergenic, or toxigenic. Bioaerosols from outdoor air accumulate on filters of heating, ventilating and air conditioning (HVAC) system in large quantities and are able to multiply there under certain conditions. In this study, silver was coated on activated carbon fiber (ACF) filters by an electroless plating method, and their efficacy for bioaerosols removal was tested. Physical filtration and biological antimicrobial test were performed. SEM and XRD analyses were used to characterize the morphology and components of ACF filters. Electroless silver-plated ACF filters showed antimicrobial efficiency, whereas pure ACF filters did not. It was found that electroless silver plating did not influence the physical filtration efficiency of ACF filters.

In recent European telecommunication base transceiver stations(BTS), a membrane laminated air filter is reported to replace a heat exchanger in order to cool internal digital units of BTS. The concept of using the air filter is for the direct ambient cooling (DAC) of BTS without heat loss generally found in the heat exchanger type BTS. In the present study, a performance evaluation experiment was conducted to investigate the pressure drop characteristics with dust loading and the particle collection efficiency of the air filter for the DAC of BTS. Finally, the long term operation lifetime of the air filter for BTS was suggested with a given fan rotation speed.

The purpose of this study was to investigate the concentration of aldehydes from new apartments in three cities(Suncheon, Yeosu, and Gwangyang) of Chonnam region. The target apartments were within 3 months after the completion of construction. Aldehydes were sampled using 2,4-DNPH cartridge and analyzed by HPLC. Temperature and relative humidity were monitored continuously every one minute by digital temperature and hygrometer. As the concentration ratio of formaldehyde between back-up and front cartridge was 3.94 6.97%, the 2,4-DNPH cartridge method satisfied a breakthrough problem for the sample collection. The repeatability of retention time and peak area for HPLC were excellent as 0.5 and 1.5%, respectively. The upper floor of S apartment (16 pyong) showed the highest concentration of formaldehyde as 1,093㎍/㎥. The average concentration of formaldehyde was the highest in K apartment(52 pyong) as 1,045㎍/㎥. The average concentration of formaldehyde in S apartment(16 pyong) and C apartment(25 pyong) were 872.6㎍/㎥ and 737.5㎍/㎥, respectively. The I/O ratios of formaldehyde were 56.9 60.0(mean : 59.1), 37.9 43.3(mean : 39.8) and 18.3 29.3(mean : 23.3) in K, C and S apartment, respectively. Therefore, it is believed that the indoor concentration of formaldehyde was very serious in new apartment. From these results, it is important that building material which emit low indoor pollutant should be selected for new apartments. In addition, management program for indoor air, such as using an adequate amount of adhesives, should be considered and indoor optimum condition should be maintained in new apartments.

Numerical analysis was conducted to characterize particle deposition on a heated rotating semiconductor wafer with respect to wafer diameter. The particle transport mechanisms considered in this study were convection, Brownian diffusion, gravitational settling, and thermophoresis. The averaged particle deposition velocities and their radial distributions on the upper surface of the wafer were calculated from the particle concentration equation in an Eulerian frame of reference at rotating speeds of 0 and 1000 rpm, wafer diameters of 100, 300 mm and wafer heating of =0 and 5K. It was observed from the numerical results that the averaged deposition velocities on the upper surface increase, when the wafer diameter confirms increase. The comparison of the present numerical results with the available experimental results showed relatively good agreement between different studies.

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