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Biological Air Cleaning
Effect of MERV Filters on Influenza Virus
Graphic courtesy of Steven Welty, Green Clean Air ©2009
MERV 15
HEPA
MERV 8
MERV 13
46% captured
11% captured
99.97% captured
71% captured
15,000 Flu Virions
15,000 Flu Virions
15,000 Flu Virions
15,000 Flu Virions
13,350 Flu Virions
4,350 Flu Virions
8,100 Flu Virions
4 Flu Virions
Source: Modeling Immune Building Systems for Bioterrorism Defense; Kowalski, Bahnfleth, Musser,
Journal of Architectural Engineering, June 2003, v9(2), pp222-227.