What is a MERV Rating and How Does it Affect Your Home's Air Quality?

Minimum Efficiency Report Value, or MERV, is a rating system that measures the ability of an air filter to capture particles between 0.3 and 10 microns (µm). It was designed by the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) to make it easier for people to purchase air filters. A higher MERV rating means that the filter can trap smaller air particles. When choosing an air filter for your home, it's important to consider the MERV rating.

A filter with a MERV rating between 1 and 3 captures less than 20% of large particles with diameters of 3 to 10 microns. A filter with a MERV rating between 1 and 6 can remove particles between 0.3 and 10 microns with an efficiency of 20%. Filters with higher MERV ratings should be changed more frequently (at least every three months) to avoid restricted airflow that can cause the system to operate inefficiently or even damage it. A high MERV rating is especially helpful for people with allergies or weak immune systems due to injury or illness.

MERV 11 pleated filters are also made with synthetic media and live up to Merv 8, without a significant price increase. If you have one, make sure you get an oven filter with a MERV rating lower than your system's maximum. Choosing the right MERV rating for your oven filter has a big impact on indoor air quality, your HVAC system, and most importantly, the well-being of your family. Because most of the family has allergies and grandma has a serious respiratory problem, and because there are six people who bring pollutants instead of one or two, a relatively high MERV rating is best for them. Air filters with MERV ratings higher than 13 also tend to restrict airflow because they have smaller pores to capture smaller particles. In short, a MERV rating lets you know what particle size of air an air filter will trap so you can choose the right one for your particular needs.

It helps you understand the effectiveness of an air filter so you can make sure your home's indoor air quality is safe and healthy.