*MERV = Minimum Efficiency Reporting Value. Describes the filter's ability to capture particles and ranges from 1 to 16. Typical fiberglass filter = MERV 1. The higher the MERV rating, the better the filtration. **The Clean Air Delivery Rate (CADR) represents the cubic feet of clean air produced per minute. ***One micron = 1/25,000 of an inch in diameter. ****U.S. Environmental Protection Agency, "Ozone Gernators that are Sold as Air Cleaners: An Assessment of Effective and Health Consequences," August 2006.