A photocatalytic oxidation filter including a support medium and a photocatalyst provided on the support medium is configured to oxidize target compounds within an airstream when irradiated by a light source. In one embodiment, the support structure has an air permeability of more than approximately 155 CFM/ft2. In other embodiments, the air permeability of the support structure may be at least approximately 200 CFM/ft2 or at least approximately 247 CFM/ft2. In another embodiment, the support medium is pleated and the air permeability of the support medium is less than approximately 155 CFM/ft2.
