Examination of Environmental Factors Influencing the Emission Rates of Semivolatile Organic Compounds

Some types of semivolatile organic compounds (SVOCs) that are emitted from plastics used in building materials and household appliances have been associated with health risks, even at low concentrations. It has been reported that di-2-ethylhexyl phthalate (DEHP)—one of the most commonly used plasticizers—causes asthma and allergic symptoms in children at home. The amount of emitted DEHP, which is classified as a SVOC, can be measured using a microchamber by the thermal desorption test chamber method. To accurately measure the SVOC emission rates, the relation between SVOC and environmental factors should be clarified. Herein, we examined the effects of the temperature, relative humidity, concentration of airborne particles, and flow field in the microchamber on SVOC emission rates. The flow fields inside the microchamber were analyzed via computational fluid dynamics (CFD). The emission rate of SVOC released from PVC flooring increased under high temperatures and at high concentrations of airborne particles but did not depend on the relative humidity. From an evaluation performed using an index of air change efficiency, such as the air age and the coefficient of air change performance, we found that a fixed air exchange rate of 1.5 h−1 in the microchamber is desirable.