Minimum efficiency report values, or MERV, indicate the ability of a filter to capture larger particles between 0.3 and 10 microns (µm). If you're looking to understand what the MERV rating is, you've come to the right place. In short, a MERV rating lets you know what size of air particles an air filter will trap. A higher rating means that the filter can trap smaller air particles.
In other words, it tells us “how effective is your air filter?” The MERV classification gives us an idea of how well filters (air purifiers, ovens) can filter particles from 0.3 to 10 microns (10-6 m). This size range includes most air contaminants: smoke, dust, the smell of cooking oil, mold spores, and bacteria. On the MERV scale, you can see that the MERV 10 filter will filter 85% of particles from 3.0-10.0 μm. In most homes and commercial buildings, filters with a MERV rating between 8 and 13 will sufficiently filter the air.
The American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) suggests the MERV 13, but it may not be the most efficient option for some residential HVAC systems. To protect yourself from bacteria that spread viruses, it's best to use a category 13 MERV filter. However, you should also consider adding air quality solutions to your home. Filters with a MERV rating greater than 13 are tightly interlocked to capture potentially harmful contaminants.
While the ratings don't exceed MERV 16, high-efficiency particulate air (HEPA) filters trap the smallest particles at a faster rate than even MERV 16. These are typically used in surgical operating rooms, clean rooms, and other settings that require absolute cleaning. When choosing an air filter for your home or commercial building, consider your family's needs and environment. An 8 to 13 MERV filter should be sufficient for most households.
You can also use an indoor air quality monitor to help you determine if a separate air purification system is needed. It's important to note that some sites on the Internet talk about MERV 17-20 filters, but the EPA and ASHRAE only rank them on the MERV scale from 1 to 16. A MERV 13
rating of 1 to 6 is the lowest of the MERV ratings, but that doesn't necessarily mean that a filter with a rating within this range should be ruled out.
MERV 13 filters also remove bacteria, tobacco smoke, car fumes, insecticide dust, pet dander, and more. It's important to choose an appropriate filter for your needs and environment in order to ensure optimal air quality in your home or commercial building.
