Study on indoor air quality in wooden houses in Japan

In Japan, guideline values for indoor air quality for a total of 13 VVOCs (highly volatile organic compounds) and VOCs (volatile organic compounds) were published by 2002. However, approximately 20 years have passed since the publication of the guideline values, and the use of new chemical substances has increased as substitutes for the regulated substances, and sick building problems caused by unregulated substances have been reported. The aim of this study is to investigate sick house issues by measuring existing regulated and unregulated substances in newly built wooden houses and evaluating indoor air quality. A total of 10 rooms in three houses were targeted for measurement and air quality was measured using active methods. The substances measured were 13 regulated substances and 16 uncontrolled substances. The results of the measurements showed that, among α-pinene and limonene, which are commonly detected in wood, the concentration of α-pinene exceeded the LCI reference value, while for limonene it was less than half of the LCI reference value. The concentrations of unregulated substances other than α-pinene were below the LCI standard values.