An HVAC system installed in your home can collect and trap the allergens, dust, and other microorganisms found in the air. As such, this form of filtration is necessary for revitalizing the quality of indoor air. But, how can you gauge the efficiency of your air filter?
The answers lie in the MERV rating, which is the filter’s minimum efficiency reporting value. Created by the American Society of Heating, Cooling, And Specialty Air Conditioning Engineers, this metric measures the filter’s capacity to stop the contaminants from entering the air stream.
Decoding the MERV Rating System
With a range from 1 to 20, the MERV ratings consider one as the lowest filtration level and 20 as the highest. Typically, MERV 16 through 20 are excellent for clean rooms, hospitals, nuclear power plants, and other places where absolute cleanliness is mandatory. Filters with MERV rating of 16 and below are ideal for residential and commercial purposes.
Every https://filterking.com/air-filter-sizes/20x30x1 goes through heavy testing based on the contaminant size. Each time, the number of particles entering and leaving the filter is counted to determine the filtration percentage. The minimum of these percentages is the official measurement determining the MERV rating.
- MERV 1 to 4: Known to block dust mites, carpet fibers, cockroach debris, sanding dust, pollen, textile fibers, and spray paint dust. Consider replacing these filters once every month.
- MERV 5 to 8: Often found as 1-2 inch pleated filters, they block dust mites, mold spores, hair spray, and pet dander
- MERV 9 to 12: These deep, pleated filters effectively remove legionella, nebulizer droplets, and humidifier dust
- MERV 13 to 16: Saliva droplets, bacteria and dust arising from smoke
- MERV 17 to 20: Used where complete elimination of airborne contaminants is needed. These filters can block virus carriers, carbon dust, sea salt, microscopic allergens, tobacco smoke, and bacteria.
How to Choose the Right Air Filter
Air Filter Ratings
Mechanical air filters are predominantly used in residences, thanks to the synthetic fibers that trap even the minute debris. While a lower MERV rating implies a low-quality filter, a highly rated filter may not always fit your home. Filters depend on your home’s size and the condition of the heating and cooling system. Filters with a rating higher than manufacturer-recommended may impair its performance. Choose a filter like filterking.com/air-filter-sizes/20x30x1 that maintains a balance between adequate air flow and eliminating the airborne contaminants.
Type of Air Filter
- Fiberglass filters: these come with a flat surface for trapping air particles. They are thin and developed for the protection of heating and air conditioning equipment. They are the cheapest available form and are quite ineffective in improving indoor air quality. With a MERV rating between 1 and 4, they remove under 10% of your home’s pollutants.
- Pleated filters: the overall efficiency of these filters depends on the number of pleats per foot. The more pleats, the better airflow in your home. They have a MERV rating of 10 to 13 and can remove up to 45% of air contaminants.
Size of the Particles
Remember, air filters with better micron ratings do not eliminate the need for dusting. While they improve the air quality, larger dust particles tend to settle elsewhere before reaching these filters. Fiberglass filters are useful in trapping large particles while other high-efficiency ones excel in trapping the smaller particles.
Filtering harmful air particles reduces the possibilities of infectious diseases. Installing the right air filter for your home is key to lowering particle exposure time and lead to better health outcomes.