Fungal colonization of air filters for use in heating, ventilating and air conditioning (HVAC) systems.

Describes how new and used cellulosic air filters for HVAC systems including those treated with antimicrobials were suspended in vessels with a range of relative humidities, and containing non-sterile potting soil to stimulate fungal growth. Prior to suspension in the chambers most filters yielded fungi, but only two of 14 non-treated filters demonstrated fungal colonization following use in HVAC systems. Antimicrobial-treated filters, in particular a phosphated amine complex showed a lot less fungal colonization than nontreated filters. States that when compared to non-treated cellulosic filters, fungal colonization of antimicrobial-treated cellulosic filters was selective and delayed.