Many air purifiers have been developed and released with increasing PM. In generally, the performance of air purifiers has been evaluated in the environment chamber by relevant standards. However, as there is a lack of information about air cleaning performance of air purifier in the living area, consumers have difficulty with product selection. In this study, five air purifiers were tested in apartments with different structures. In order to examine the effect of air purifiers, we assumed 3 cases such as inflow of pollutants from outdoors by ventilation, smoking patterns of residents, and cooking methods (e.g., frying fish). The evaluation results showed that the efficiency of air purifier products D and B of the 3-stage configuration (pre-filter + HEPA filter + activity carbon) was the best in most experiments. In the case of the ionizer type E product, the efficiency was very low and, at times, had increased the particulate matter indoors. Considering the cost-performance ratio, it is most reasonable to use an air purifier comprising a pre-filter and a HEPA filter without an additional configuration.

While the air quality of public facilities such as daycare centers is managed by law, the management of air quality in residential buildings is not mandatory. For this reason, air quality in an apartments has not been well surveyed. In this study, we investigated the influence of cooking and ventilation on the indoor air quality in an apartment. Continuous measurements were performed using real-time monitoring instruments from June 9 to 17, 2014 in Seoul, Korea. A CO2 meter was used to measure CO2 concentration and temperature. A portable aerosol spectrometer (0.25-32 μm), a nanoparticle aerosol monitor (10-1,000 nm), and an aethalometer (total suspended particulate, black carbon) were also used. During the measurement period, ventilation and cooking activities were observed 8 and 10 times, respectively. In 5 of the observed cases, both activities were done simultaneously. During the ventilation, CO2 concentration and temperature were decreased; however, particle concentrations were increased. When cooking was done, particle concentration was increased in some cases; however, CO2 concentration and temperature were unchanged. Combined cased CO2 concentration and temperature were decreased and particle concentrations were increased.

Recently, the air pollution have bad effects on the indoor environment. Many buildings around the world use natural ventilation. to remove the air pallutant. But, nowadays, ventilation requirements can be demanding, as modern systems require greatly improved reliability and control. The fan and the duct are used to remove air mechanically from the space. Until now, apartment houses have been relying on the duct supply system ventilation rather than other system ventilations. Therefore, the establishment of a prediction method based on optimal ventilation energy consumption using duct supply system and ductless is the ultimate goal of this study. As a result, this study found that the characteristics of duct and ductless supply system ventilation are dependent to each exhaust system. Consequently, the local supply indices of the duct supply system is definitely superior about 24.6% ~ 26.4 % than those of ductless supply system. However, the duct supply system has greater pressure drop in ventilation area than ductless, and duct system needs a lot of ventilation energy. In this study, The ductless supply system has advantage over the duct system about 14.8 % as duct exhaust system and 20.0% as ductless exhaust system in terms of modified local supply indices.

Exposure to nitrogen dioxide (NO₂) can produce adverse health effects. Various indoor and outdoor combustion sources make NO₂ the most ubiquitous pollutant in the indoor environment. 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. In the present paper, we used a mass balance model and regression analysis, penetration factor (ventilation rate divided by the sum of ventilation rate and deposition constant) and source strength factor (source strength divided by the sum of ventilation rate and deposition constant) were calculated using multiple indoor and outdoor measurements with 10 houses. Subsequently, mean contributions of indoor and outdoor sources were 28.86% and 81.09%, respectively, suggesting that both indoor and outdoor sources had contributions to indoor concentrations of NO₂.

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.

Recently, concern about Sick House Syndrome (SHS) has been increased in Korea. And it is suspected that formaldehyde (HCHO) and volatile organic compounds (VOCs) are major factors for SHS. This study was surveyed the indoor air quality in new apartments in Korea. The HCHO and VOCs were measured at 90 sites and analysed by HPLC-UV and GC/MS, respectively. The range of HCHO concentrations at 90 sites were 9.39∼248.78㎍/㎥ and the mean value 105.41㎍/㎥ and the concentrations of HCHO at 42 sites (46.7%) exceeded the indoor air quality guideline (100㎍/㎥) in Japan. Among the 4 VOCs, toluene concentrations were the highest and the mean value 127.33㎍/㎥ and that concentrations at 12 sites (13.8%) were exceeded the indoor air quality guideline (260㎍/㎥) in Japan. There was a tendency which the longer the movement and measurement period is, the more the pollutants concentration is decreased. HCHO and VOCs concentrations of domestic results was similar to Japan's survey results in 2000.

The study is about variations in Carbonyl compounds concentration within apartment buildings according to pre-residence and residence. We consecutively investigated indoor air pollutants in 120 households in 6 cities at pre-residence and residence. Carbonyl compounds were collected using the 2,4-DNPH cartridge and were analyzed using HPLC. The carbonyls concentration of indoor air in the new apartments before occupation measured formadlehyde(76.0㎍/㎥), acetone(85.9㎛/㎥), acetaldehyde(13.8㎍/㎥). The carbonyls concentration of indoor air in the new apartments after occupation measured formadlehyde(233.1㎍/㎥), acetone(128.9㎍/㎥), acetaldehyde(29.8㎍/㎥), respectively. As a result, the mean concentration of carbonyl compounds within the pre-occupancy stage was lower than those of residence.

Indoor air quality is the dominant contributor to total personal exposure because most people spend a majority of their time indoors. Especially when indoor environments have sources of contaminants, exposure to indoor air can potentially pose a greater threat than exposure to ambient air. In this study, estimations of volatile organic compounds and formaldehyde emission rate in indoor environments of new apartments were carried out using mass balance model in indoor environment, because indoor air quality can be affected by source generation, outdoor air level, ventilation, decay by reaction, temperature, humidity, mixing condition and so on. Considering the estimated emission rate of volatile organic compounds and formaldehyde, it is suggested that new apartment should be designed and constructed in the aspect of using construction materials to emit low hazardous air pollutants.