From the EPA (United States Environmental Protection Agency) Guide to Air Cleaners in the Home  This is a great piece that explains all you need to know to get started.  Questions?  Give us a call.  We'll be happy to hear from you!  http://www.epa.gov/iaq/pdfs/aircleaners.pdf

From APG:  What are MERV Ratings and How Do They Work?  Here is a great guide to information about air filters - ones being used and counted on every minute and what they can and can't do....  http://www.airpurifierguide.org/faq/merv-ratings