Surface removal rate of ozone in residences in China

Outdoor ozone has been proven to be strongly associated with both morbidity and mortality. The deposition of ozone on indoor surfaces is the main loss of ambient ozone migrating into indoor environments, which is critical for assessing human exposure to ozone. In this study, the surface removal rate due to ozone deposition on indoor surfaces in 14 residences in China was measured. The deposition velocities for the uptake of ozone were measured as well as theoretically calculated. The results indicate that the mean ± standard deviation (SD) of the surface removal rate of ozone in the studied Chinese residential rooms was 2.8 ± 1.1 h−1. The mean ± SD of the measured deposition velocity was 109 ± 34 cm/h, which is much larger than the theoretically calculated value of 27 ± 3 cm/h. The significant difference between the measured and theoretically calculated values might result from the accumulation of organic chemicals on indoor surfaces due to the occupants' daily activities. The measured surface removal rate of ozone in Chinese residences may be further applied for estimating human exposure to ozone in China, where ozone pollution has been increasingly severe.