Many people are confused about the acronym MERV. IN short, MERV ratings declare the efficiency of an air filters ability to remove particles (pollutants) from the air. This short guide goes in detain into what MERV is and what different MERV ratings actually mean for you and your family.
What is MERV?
MERV is the Minimum Efficiency Reporting Value, which is the scale designed by the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) to rate the effectiveness of air filters. Basically, the higher MERV rating indicates higher filtering performance.
The most recommended MERV ratings for residential filters are between MERV 7 and MERV 13. In fact, filters with these MERV ratings perform as efficiently as true HEPA filters. They all basically trap the same range of particulates, particulates such as dust particles, mold spores, dust mite debris, tobacco smoke, pet dander, and pollen, but each filter has a higher capturing capacity the higher the MERV.
There are really two different components of a MERV rating. One is the ability to remove large airborne particles, or particles that are between 1 and 10 microns. These “large” particles include pet dander, pollen grains, dust mite debris, etc. However, the bulk of indoor air pollutants are in a smaller size range. MERV also rates the filter’s ability to remove submicron particles, those that are smaller than 1 micron; this rating is called the Microparticle Performance Rating (MPR), and some filters are given just this rating.
MERV 6 is the lowest MERV rating offered by AirFilters.com. Though not recommended for allergy and asthma sufferers, filters with a MERV 6 rating are 8 times more efficient than the regular cheap fiberglass filters. Filters with a MERV 6 rating will remove large particles like allergens, dirt, debris, lint, dust, etc. The advantage of having a MERV 6 rated filter is that it is more affordable.
If you are looking for an ordinary household air filter for maintaining efficient airflow and better air system performance, then MERV 8 is the filter you need. MERV 8 rated filters are high quality filters. MERV 8 filters remove basically the same particulates as a MERV 6, but they are more efficient; with a dust spot efficiency of 30-35%, they are 20 times more efficient than regular fiberglass filters.
Filters with a MERV 11 rating have a dust spot efficiency of 60-65% and are 30 times more efficient than regular fiberglass filters. MERV 11 rated filters are good filters for households with breathing sufferers. Not only do they provide superior residential filtration, but they also provide a healthier breathing environment.
If you suffer from breathing problems such as allergies or asthma, then AirFilters.com recommends a filter with a MERV 13 rating. MERV 13 rated filters have a dust spot efficiency of 80-90%, and they are highly efficient filters both for residential and commercial use. MERV 13 filters remove a higher range of particulates, including larger amounts of bacteria and even some viruses, and they are best for people suffering from breathing problems. Also, for their high capturing capacity, they still maintain a low resistance to airflow.
MERV 8, MERV 11, and MERV 13 are the most common filters for residential use. Anything below a MERV 6 is not recommended for home air systems because they are not highly efficient. However, filters with MERV ratings above a MERV 13 tend to restrict airflow; the higher the MERV, the higher the restriction of airflow. That is why AirFilters.com recommends between MERV 8 and MERV 13 for a household air filter.