The concern with indoor air pollution has been growing as a serious social problem since the 1990s in Japan, the Ministry of Health, Labour, and Welfare has established guidelines for addressing indoor chemical substances, and the amended Building Standards Law has restricted the use of building materials containing formaldehyde and required rooms to have ventilation equipment. The purpose of the present study was to examine the effects of differences in the building material specifications on indoor air quality. Two student dormitories were selected for investigation: a student dormitory remodeled using interior finishing materials containing low- formaldehyde substances; and a dormitory built according to conventional specifications. Indoor formaldehyde concentrations were lower than the guideline established by the Ministry of Health, Labour, and Welfare, even in summer under high-temperature conditions, due to the implementation of the policy to reduce chemical substances in building materials and the effects of the restrictions. However, problems were identified in terms of increases in indoor concentrations after installation of furniture, and mean concentrations during sleeping hours. Ventilation performed by residents effectively reduced mean formaldehyde concentrations. To maintain appropriate indoor air quality, it is important for residents to pay attention to ventilation and room furniture, and their lifestyle, in addition to the selection of building materials.

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We examined 200 college students, at rest in a sitting position in an air-conditioned classroom, to investigate the differences in physiological and psychological responses between men and women in the thermoneutral zone of SET*. The percentage of women who reported suffering from the cold more often in an air-conditioned environment was higher than that of men. The number of clothing items and the clothing insulation value, estimated using International Organization for Standardization (ISO) 9920 were higher for the women than for the men, based on the students’ own everyday clothing choices as worn during the experiments. However, the percentage of body surface area covered by clothing worn by the women was significantly lower than that for the men. Although oral and skin temperature decreased in both men and women after 60 min of exposure to a temperature of 25 °C, the oral and skin temperatures of the women’s forehead and palms were significantly lower than those in the men. Moreover, the decrease in the women’s oral temperature was greater than that of the men. Women felt cooler and more uncomfortable than men did in the ASHRAE comfort zone, with SET* of 22.2–25.6 °C. Gender differences in physiological responses, and differences in the clothing typically worn by men and women, might affect psychological responses to the moderate thermal environment encountered in daily life.

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Thermal manikin is a device, which simulates not only body shape but also human heat production and release. The device contributes to evaluate human heat transfer, thermal resistance of clothing, and protective tools for human safety with a high representativity. According to a study using the thermal manikin, for example, convective heat transfer from the human body has been found to be different in individual body location. The convective heat transfer coefficients in extremities are so larger than those in trunk and head that it is reasonable to put gloves on hands, e.g., to effectively protect the extremities from heat loss in a cold. In natural convection system, it has been experimentally confirmed through the thermal manikin that the convective heat transfer coefficient decreases with decrease in ambient pressure. Therefore, during exposure to a low ambient pressure, even if in a cold, temperature drop in skin surface can be suppressed because of the depressed sympathetic nerve activity and of the decrease in the convective heat transfer coefficient. A baby thermal manikin aged 0.5 year-old has been originally developed with aiming for infant’s safety and thermal comfort. There is a significant difference in convective heat transfer in the whole body between infant and adult because of difference in height; the coefficient is larger in infant than in adult. The baby thermal manikin has been employed for measuring the thermal resistance of clothings for infant. An estimation equation by means of the total weight of the clothing for infant has been derived to obtain the thermal resistance, because a high correlation has been confirmed between them.

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