Reduces up to 65% of airborne particles as small as 1 micron while catching pollutants such as Smog, pollen, smoke, pet dander, mold spores, and fine dust as small as .3 microns. MERV 11 at a minimum is 20% efficient at capturing particles of this size; providing a baseline for in-line protection capturing particles that are vectors for infectious diseases. MERV 11 is the lowest rating on the MERV scale that catches E1 particles (0.3 microns to 1 microns in average diameter). This means that it provides a critical level of protection and air filtration that positively impacts your health.