Ozone deposition velocities on cotton clothing surface determined by the field and laboratory emission cell

Abstract

Interfacial ozone-initiated chemistry can greatly influence human exposure to reactants and products in the indoor environment. As the nearest reaction interface to human body, clothing assumes an important role in the generation of ultrafine particles and volatile organic compounds when reacting with indoor ozone. However, little is known about the kinetics of ozone-clothing reactions. This investigation developed a convenient method to examine the reaction kinetic parameters of ozone-clothing reactions by using a field and laboratory emission cell. Deposition velocity can be determined in a short period by this method. The study found that the deposition velocity and reaction rate constant for ozone-cotton vest reactions were not significantly affected by the ozone concentration, air flow velocity and long soiling duration (>6 h) of the vest. However, whether or not the vest had been soiled with skin oil is key to the magnitude of the deposition velocity and reaction rate constant. The ozone deposition velocities on soiled cotton vest surface are approximately constant under typical indoor conditions. The deposition velocity and reaction rate constant of ozone-initiated reactions with soiled cotton vest are 0.79 ± 0.17 and 2.43 ± 0.71 cm/s, respectively, at room temperature.