MERV Ratings Determine Effectiveness, So Choose Your Air Filter Wisely

Using a quality air filter and keeping it fresh are important factors in maintaining both your HVAC system and your family’s health. Choosing the right one can prevent dust and dirt from circulating with your indoor air and from accumulating in your heating and cooling equipment, where it reduces performance. Tampa Bay homeowners can better understand which air filter is best for their home by learning about MERV.

What do we mean when we talk about air filter efficiency? We’re talking about the number of particles in a certain size range that the filter can remove from passing air streams. A 100 percent efficient filter would trap 100 percent of particles in a certain size range.

Filter efficiency is rated by Minimum Efficiency Reporting Value, or “MERV.” MERV rates filters on a numerical scale ranging from 1 to 16. MERV 1 to 4 is typically the lowest performing range. MERV 13 to 16 filters perform the most efficiently. MERV 16 filters are verified capable of trapping 95 percent of particles that are as small as 0.3 microns. An example of particles of this size include:

  • Dust
  • Dust mites
  • Pet dander
  • Mold and other allergens
  • Bacteria
  • Microorganisms
  • Fume particles from household toxins, such as cleaners and air fresheners

HEPA, or High Efficiency Particulate Air filters, are in a class all their own, and are held to higher standards. A conventional filter that earns a MERV 16 will actually be less efficient than a HEPA filter rated MERV 16. HEPA filters have more surface area than others, since they have more pleats per inch of matting, and must be capable of capturing at least 99.97 percent of particles 0.03 microns small in order to earn the HEPA label.

High efficiency filters restrict more airflow. Not every HVAC system is designed to work with airflow restricted to this degree, so it’s not the best idea to run out and install a HEPA without having your system evaluated first. Conact Simpson Air in Tampa today to learn more about which filter would be ideal for your system. We’ll be happy to help!