MERV 11

What does MERV measure and what does it mean?

MERV, or Minimum Efficiency Reporting Value, is a numerical value given to filters in order to identify its filtering abilities.

This is now an international industry standard set up by the committee that oversees the filter industry. This standard is used for determining the filters ability to capture and hold dirt and dust in specific size ranges. Some filter manufacturers such as 3M use their own rating system, which is not approved as an industry standard.  

MERV Rating Average Particle Size Efficiency in Microns
1-4 3.0-10.0 less then 20%
6 3.0-10.0 49.9%
8 3.0-10.0 84.9%
10 1.0-3.0 50%-64.9%, 3.0-10.0 85% or greater
12 1.0-3.0 80%-89.9%, 3.0-10.0 90% or greater
14 0.3-1.0 75%-84.9%, 1.0-3.0 90% or greater
16 0.3-1.0 75% or greater

A human hair is usually 60-100 microns in width.