Minimum Efficiency Reporting Value Rating system created for air filters with a scale that represents the worst case performance of a filter when dealing with particles in the range of 0.3 to 10 micrometers. The scale is from 1-16. The higher the MERV rating the greater the percentage of particles that will be captured. 10 MERV Rated Air Flow 1400 CFM Static Pressure Drop 0.23 in. w.c.