VOC emissions in vehicular environment: Observation and prediction

To study VOC emission and transmission characteristics in sealed new car, we conducted field measurements in different weather for 12 days. Interior and exterior air temperature was strongly correlated, while the relative humidity was weakly correlated. The material surface temperature (maximum 91.1^oC) and the is at most 46^oC difference. The temperature difference may result in a higher air exchange rate during the day (0.205-0.378 h^-1) than at night (0.065-0.113 h^-1). 20 VOCs were detected, and formaldehyde and acetaldehyde exceeded the safety limit set by GB/T 27630-2011, with the over-standard rates of about 34.9% and 60.5%. Predicting formaldehyde concentration at dynamic temperature via modified multi-source model shows that material surface temperature was more responsive to VOC emission than air temperature.