The researchers also tested the hybrid filters in an environmentally controlled laboratory chamber to come up with the air-exchange rate for the therapy pool assays, among other parameters.
The researchers published their results in the Feb. 2005 issue of the Journal of Air & Waste Management Association. The study was supported by funds and equipment provided by Honeywell, Inc., UlraViolet Devices, Inc., and the National Science Foundation.
Angenent's collaborators are: Elmira Kujundicz, David A. Zander, and Mark Hernandez, of the University of Colorado Department of Civil, Environmental, and Architectural Engineering; and David E. Henderson and Shelly L. Miller, of the Department of Mechanical Engineering, University of Colorado.
Bioaerosols pose a threat to public health through infectious and toxic diseases. Today there are increased settings where people gather and can be affected by such bioaerosols. Among these "high-exposure environments" are correctional facilities, homeless shelters, healthcare facilities, and public transit systems. Additionally, the advent of hot tubs, hospital therapy pools and other warm-water leisure and therapy pools, many bioaerosols researchers believe, creates harbors that enhance the aerosolization of microorganisms, including strains of Legionella and Mycobacterium, that can cause diseases such as "lifeguard lung."
"The results of this study suggest that a reasonable reduction in bioaerosol concentrations can be achieved by installing this new generation of hybrid air filters," the authors conclude. "Engineering control methods must be balanced with constraints such as occupant comfort, economic factors, and building management strategies to ensure that the health risks associated with bioaerosol exposure are as low as practical."