Associations of emission factors of formaldehyde and benzene series with area-specific infiltration air flow in bedroom of Shanghai residence

In recent years, more and more attentions were paid to indoor air quality, for indoor air pollution would cause severe health outcomes on people. It had been found that the concentrations of indoor air pollutants were closely related to ventilation. In this paper, the associations between concentrations of indoor pollutants (formaldehyde and benzene series) and infiltration air flow were discussed. 149 children’s bedrooms with doors and windows closed at night were observed in Shanghai. Air change rates of bedrooms were calculated by tracer gas method. The concentrations of formaldehyde and carbon dioxide were detected. Air samples were collected and Gas Chromatography-Mass Spectrometer (GC-MS) was used to obtain the concentrations of different kinds of benzene series in air, and then the sum of concentrations was obtained. The area-specific infiltration air flow (Q/A) in the residence during night ranged from 0.05 ~ 4.32 mh^-1, and concentration of formaldehyde and benzene series at night ranged from 6.8 ~124.7 µg·m^-3 and 1.2 ~ 227.7 µg·m^-3, respectively. With the increase of area-specific infiltration air flow (Q/A), the emission factors (EFs) of formaldehyde and benzene series had a rising tendency. The associations of EFs of formaldehyde and benzene series with Q/A were also assessed during different building characteristics. The highest effect of Q/A on EFs of formaldehyde and benzene series were found in children’s bedroom on ground floor. This study provided basic data for proposing limits value of different indoor air pollutants in standard of residence and decreasing the health risk of these pollutants.