In response to the ongoing debate as to the appropriateness of incorporating antimicrobial agents into fibrous air filter media, ASHRAE funded research project RP-909, "Determine the Efficacy of Antimicrobial Treatments of Fibrous Air Filters." The objective was to generate data that would provide the ASHRAE members with information that would help them decide the value of adding antimicrobial treatments to their filter media. A combination of laboratory and field testing was performed to determine the efficacy of antimicrobial agents on fibrous air filters and the potential ability of these treatments to inhibit filter media surface growth and subsequently reduce indoor air microbiological particulate contamination.

The study showed that the appropriate use of antimicrobial treatments on filters is a complex issue. The filtration efficacy was not affected by the presence or absence of the antimicrobial treatment. Two of the three antimicrobials inhibited growth of the test organisms on new filters. The third did not. Dust loading enabled the fungi to grow even on the filters treated with an antimicrobial agent.

Units: Dual