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As concern about IAQ has increased, forced-air distribution systems are being viewed as a potentially important factor in preventing the transport of indoor and outdoor pollutants. Duct leakage can be a confounding factor in attempts to use the forced-air system for this purpose. Leakage from outside into the return side of the system brings outdoor air directly into the distribution system through the leak. Supply leakage depressurizes the house which increases infiltration of outdoor air through the envelope.

Guideline for ventilation to improve indoor air quality in apartment housings in Korea was recently enacted and natural or mechanical ventilation system has become mandatory. Meanwhile, as the height of residential buildings goes up, the performance of ventilation system is influenced by stack effect especially in winter. This study is to review how stack effect influences ventilation system in high-rise residential buildings through simulations.

In order to clarify the association between indoor environmental factors and children’s health problems, indoor air quality was investigated during the winter and rainy seasons in Japan. The total of 209 houses was classified into case and control groups whether the child have allergy symptom or not. The number of the houses in case and control groups is 133 and 76, respectively. This survey included measurement of indoor temperature, humidity, the pollution of chemical compound and mite allergen (Der 1). These measurements were conducted in the living room and children’s room.

Recent studies show the number of people affected by biological contaminants have increased every year in Japan. An epidemiological investigation on 4th and 5th grade primary school students was conducted in order to clarify the relationship between indoor environment and children’s health problems. A case-control study adopted ATS-DLD-American Thoracic Society-Division of Lung Diseases- questionnaire for evaluation of respiratory symptoms and allergies was conducted for 2574 primary school students (1664 responded) across Japan.

Child care center, one of the public facilities, has recently been increased. It is because of the government's childbirth policy. In particular, infants and children who use this place are frequently exposed in danger because of their biological characteristics. They stay in child care center over 7 hours a day in average. Therefore, the importance of the child care center's indoor air has been increased. Thus, survey and investigation of the child care center's indoor air are conducted in this study.

Rotary heat recovery exchangers are widely used in ventilation systems, and the units are known for their high efficiency and almost maintenance-free operation. Temperature efficiencies above 80% are not uncommon. Performing dynamical analyses of rotary heat exchangers are in many situations advantageous, especially in connection to installation of such equipment in VAV systems. Efficiencies and flows are varying parameters that are crucial for energy calculations, but also for control. The dynamical analysis can effectively be carried out by addressing a dynamical model.

Furniture can raise indoor air contaminants with toxic emissions of VOC and formaldehyde.. While furniture is classified as a subject of safety and has quality labeling, there is a lack of domestic regulations related to contaminant emissions with the exception of sinks. When looking at the analysis on environment-related patients related to the smell or odors from furniture every year, patients suffering from asthma, allergic rhinitis, and atopic dermatitis are on the rise.

Total heat recovery type ventilators that are connected to each room with ducts are mainly installed in Korea, but they raise concern over duct pollution. In this study, indoor environments made by thin line type ventilators installed in dwelling units of apartment houses are investigated by CFD. Results show the case that thin line type ventilators installed in each room - including kitchens - make the best indoor environment that maintains air velocity at under 0.25m/s, and evenly distributes the age of air in all areas.

The use of CFD technique for predicting the properties of airflow fields and particle movement is effective to carry out parametric study intended for a wide range of particle sizes. In this study, particle dispersions due to turbulent flow and thermophoretic effect were analyzed for a simplified ventilator model. Numerical results that comprise a classification of particle motion, temperature difference and particle diameter were reported.

As part of a field measurement project of unvented gas fireplaces in 30 homes, portable carbon monoxide sensors were located in several places in each home. This was done to assess the degree to which combustion by-products became distributed throughout the home. The sensors indicated that carbon monoxide levels began rising throughout the home almost immediately, at or near the one-minute sampling interval. The results show that, on average, the reading in the middle of the fireplace room was about 95% of the reading at the mantel.