When it comes to protecting your home or business from airborne particles, including the novel coronavirus, MERV-13 is the minimum filter rating we recommend. This rating is designed to capture particles in the 3-10 µm range, with 85% efficiency for particles in the 1-3 µm range and 50% efficiency for particles in the 0.3-1 µm range. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) recommends a MERV rating of 13+ for reopening during the COVID-19 pandemic. This rating is designed to capture 1 micron sized particles, which are effective for capturing COVID-19 virus particles indoors.
For HVAC systems, ASHRAE recommends a filter with a minimum MERV rating of 13, but MERV 14 or higher is preferred. MERV 14 and higher can capture particles that are even smaller than previous MERV ratings, ranging from 0.3 to 1.0 microns in size.So, does a MERV 11 filter capture coronavirus? Unfortunately, no. A MERV 11 filter is not designed to capture particles as small as the novel coronavirus, which is why ASHRAE recommends a minimum MERV rating of 13+.