What is MERV? How do you choose the right MERV rating for your home or facility, and is it important?
You buy air filters whether you own a home or manage a business. You do this because indoor air quality is essential, and every HVAC system requires you to change the filters regularly. Your air quality and circulation efficiency depend on clear, clean, unclogged air filters as part of the system.
If you go to the store or search for air filters online, you’ll need to know your unit’s filter size and your desired MERV rating. The filter size you get is based on your unit specs. But what is MERV? How do you choose the right MERV rating for your home or facility, and is it important?
What Is MERV?
MERV stands for Minimum Efficiency Reporting Values. This rating measures how well a filter stops and contains airborne particles between 0.3 and 10 microns large. This includes dust, pollen, mites, and mold spores.
MERV ratings range from 1-20. A lower MERV rating only stops large particles of dust and pollen. A higher MERV rating contains all particles down to a much smaller size and will improve your indoor air quality without making your energy costs rise significantly.
MERV Rating Chart
MERV Rating
- MERV 1 – 4
- MERV 5
- MERV 6
- MERV 7
Average Particle Size Efficiency in Microns
3.0-10.0 microns at 20% efficiency
3.0-10.0 less than or equal to 20%
3.0-10.0 less than or equal to 35%
3.0-10.0 less than or equal to 50%
- MERV 8
1.0-3.0 less than or equal to 20%
3.0-10.0 less than or equal to 70%
- MERV 9
1.0-3.0 less than or equal to 35%
3.0-10.0 less than or equal to 75%
- MERV 10
1.0-3.0 less than or equal to 50%
3.0-10.0 less than or equal to 80%
- MERV 11
0.30-1.0 less than or equal to 20%
1.0-3.0 less than or equal to 65%
3.0-10.0 less than or equal to 85%
- MERV 12
0.30-1.0 less than or equal to 35%
1.0-3.0 less than or equal to 80%
3.0-10.0 less than or equal to 90%
- MERV 13
0.30-1.0 less than or equal to 50%
1.0-3.0 less than or equal to 85%
3.0-10.0 less than or equal to 90%
- MERV 14
0.30-1.0 less than or equal to 75%
1.0-3.0 less than or equal to 90%
3.0-10.0 less than or equal to 95%
- MERV 15
0.30-1.0 less than or equal to 85%
1.0-3.0 less than or equal to 90%
3.0-10.0 less than or equal to 95%
- MERV 16
0.30-1.0 less than or equal to 95%
1.0-3.0 less than or equal to 95%
3.0-10.0 less than or equal to 95%
The most efficient air filter is called a HEPA filter. HEPA stands for high-efficiency particulate air. This air filter can theoretically remove at least 99.97% dust, pollen, mold, bacteria, and any airborne particles with a size of 0.3 microns.
Contact Thomas Hoffmann Air Conditioning and Heating
Whether you’re a business manager or a homeowner, Thomas Hoffmann Air Conditioning and Heating can help you determine what type of filter is right for your needs. With more than 30 years of experience and a master technician and mechanical engineer as our owner, we can replace, repair, and provide maintenance for your business or home’s HVAC system.
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