According to the Environmental Protection Agency (EPA), the level of indoor air pollutants can increase when temperatures are high. With summer just around the corner, Cleveland homeowners should prepare now to protect their indoor air quality.
Implementing High Efficiency Particulate Air (HEPA) filtration is an excellent method. Unlike other air filters, which trap airborne particles in a tight grid of small pores, HEPA filters capture pollutants within a network of randomly spaced fibers, typically composed of fiberglass, using the following three methods:
Interception. Usually effective against particles over .4 microns, HEPA filtration causes particles to adhere to any fibers they near almost as if by magic. It’s as though the fibers actually reach out and “catch” the particles.
Impaction. Also effective against particles over .4 microns, impaction occurs when particles caught within the airflow collide directly with the fibers and remain embedded therein. Impaction is most effective at greater airflow velocities.
Diffusion. Commonly effective against particles below .1 micron, diffusion causes the particles to collide with air or other gases, which delays their passage through the filter until one of the above methods effectively captures them.
HEPA filtration can be installed into your existing HVAC system, or is available as stand-alone air purifiers, but buying the “strongest” filter is not necessarily cost-efficient. The EPA states that cleaners with a Minimum Efficiency Reporting Value (MERV) of 7 to 18 are almost as efficient as true HEPA filters for most common uses, and tend to be less expensive and quieter. In small, portable air cleaners, medium-efficiency filters may actually be preferable due to HEPA filters’ lower air delivery.
To meet U.S. governmental standards, filters must remove 99.97 percent of particles greater than .3 microns to qualify as HEPA; however, they cannot trap harmful gases. Homeowners concerned about gaseous pollution should also consider combining HEPA filtration with some other system, such as activated carbon filters.
For any questions you may have about HEPA filtration or other methods of improving your indoor air quality, contact us at Stack Heating & Cooling. We’ve been providing professional service to the greater Cleveland area since 1976.
Our goal is to help educate our customers in Cleveland, Ohio about energy and home comfort issues (specific to HVAC systems). For more information about HEPA filtration and other HVAC topics, download our free Home Comfort Resource guide.
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