What is a MERV Air Filter?

Air filters come in various specifications: materials, densities, structures, etc. All of these contribute to the quality a filter brings in capturing impurities from the passing air. To better understand the quality of each product, you need to take a look at its MERV level.

What is a MERV Air Filter?

MERV stands for Minimum Efficiency Reporting Values. This rating represents how capable a filter is in capturing particles of 0.3 to 10 microns. The MERV air filter system was developed from the ASHRAE test method. The higher the rating means the more impurities the filter can block.

MERV Rating Chart

A lower MERV rating doesn’t mean the filters are useless because each efficiency level has allotments. On the other hand, getting an extremely high MERV air filter could be a waste of money.

To provide a little more perspective, here are what air filters can do on different levels:

MERV 1-4

• 20% effective for capturing particles of 3.0 to 10.0 microns.
• Reliable for capturing pollen, dust mites, sandy dust, and textile fibers.

These filters are commonly used as pre-filters in commercial buildings. They can also work for residential furnaces and window ACs in preventing debris from damaging the inner system, but not enough to improve indoor air quality.

MERV 5-8

• MERV 5 and 6 are 49.9% effective for capturing particles of 3.0 to 10.0 microns.
• MERV 7 and 8 are 84.9% effective for capturing the same-sized particles.
• Reliable for capturing particles as mentioned above, as well as mold, spores, hair spray, pet dander, and dust lint.

Air filters in this category are most commonly  used as pre-filters or final filters in commercial and residential buildings. They can also be sufficient in the industrial workplace and paint booth inlets.

MERV 9-12

• MERV 9 and 10 are 85% or more effective for capturing particles of 3.0 to 10.0 microns, and 50% to 64.9% effective for capturing particles of 1.0 to 3.0 microns.
• MERV 11 and 12 are 90% or more effective for capturing particles of 3.0 to 10.0 microns, and 80% to 89.9% effective for capturing particles of 1.0 to 3.0 microns.
• Reliable for capturing particles as mentioned above, in addition to lead particles, car emission, legionella, and coal dust.

These filters are commonly  used as pre-filters or final filters in healthcare facilities, middle to high-class commercial buildings, and high-class residential units.

MERV 13-16

• MERV 13 and 14 are 90% or more effective for capturing particles of 1.0 to 10.0 microns, and 75% to 84.9% effective for capturing particles of 0.3 to 1.0 microns.
• MERV 15 and 16 are 95% or more effective for capturing particles of 1.0 to 10.0 microns, and 85% to 94.9% effective for capturing particles of 0.3 to 1.0 microns.
• Reliable for capturing the particles mentioned previously, plus bacteria, viruses, tobacco smokes, sneeze droplets, and finer pet dander.

These filters are typically used as final filters in healthcare facilities, high-class commercial buildings, and smoking lounges.

MERV 17 – 20

• MERV 17 and 18 are 99% or more effective for capturing particles of 1.0 to 10.0 microns, and 95% to 99.997% effective for capturing particles of 0.3 to 1.0 microns.
• MERV 19 and 20 are 99% or more effective for capturing particles of 1.0 to 10.0 microns, and 99.99997% effective for capturing particles of 1.0 to 3.0 microns.
• Reliable for capturing the previously mentioned particles, on top of microscopic viruses and allergens.

These filters are used in buildings with radioactive or carcinogen toxins. Pharmaceutical facilities and orthopedic surgery rooms may also benefit from this level of MERV air filters.

Looking into the MERV air filter is essential when browsing for filters to install on your HVAC system. By understanding how the parameters work, you will be able to determine which filter is best to buy.  More than that, you will better understand what could happen if you choose to cut corners by buying a cheaper one.

ECM Air Conditioning, with its headquarters located in Boynton Beach, FL, provides air conditioning services within Palm Beach County, Broward County, Martin County, and St. Lucie County. If you’re looking to have a new HVAC system installed, we’re on-call and ready to assist you. So if you’re in need of an HVAC installation, don’t hesitate to contact us today to schedule an inspection! Our HVAC installation experts will check your ductwork, measure, check wire sizes, and more before making recommendations to ensure maximum efficiency and comfort. Call us at 561-295-1763 or contact our HVAC installation team online by clicking here.