Effects of filters, ventilation and recirculation rates on ozone initiated chemistry products in air-conditioned buildings in the tropics

Abstract

This study examines the impact of filtration, ventilation and recirculation rate on concentration of condensed-phase, ozone (of outdoor origin) -derived oxidation products (SOA) in a model room with ventilation system that re-circulates large percentage of its supply air. Additionally, it critically evaluates potential approach for filtering re-circulated air and, also, avoiding the negative consequence of having loaded filters in a ventilation system. Increased recirculation rate not only influences the surface removal rate constant, but also increases the fraction of pollutants removed by building filters. Increased ventilation rate dilutes pollutants with indoor sources and ozone-derived products. Activated carbon filters are more effective at reducing ozone and SOA particle than filters without carbon. Even filter with quarter amount of the standard carbon content of commercially available bag-type stand-alone combination filter incorporating activated carbon significantly improves Perceived Air Quality (PAQ) than filter without carbon. This study has implication on health and building sustainability.