Know your MERV

This four-letter acronym is your key to understanding the strength of air filters, which are vital to heating, ventilation and air conditioning systems.

MERV stands for Minimum Efficiency Reporting Values,.

It rates the ability of air filters to trap certain particles. The higher the filtration rate the better the filter is at capturing dirt, debris, smoke, pet dander and other unwanted particles.

Filtration rates vary widely, from a low of 85 percent to more than 99 percent, depending on materials and cost.