FC100A Efficiency and arrestance ratings based on the American Society of Heating, Refrigerating and Air Conditioning- Engineers Standard 52.2-1999. Later upgrade to higher performing media or electronic air cleaner is easy. (Note that 25 x 20 in. and 25 x 22 in. models cannot be upgraded to an electronic air cleaner.)
High efficiency media filter (included with some models) captures particles as small as 0.3 micron.