Do Home Air Filters Really Make a Difference?

Air and HVAC filters are designed to filter out contaminants or particles from the air that passes through them. Cleaning and filtering the air can help reduce pollutants in the air, including particles that contain viruses. Air purifiers are designed to remove contaminants from the air, such as allergens, dust, spores, pollen and more. Some purifiers also capture or reduce bacteria, viruses, and odors.

However, not all units will be able to do so. At its most basic function, an air filter removes impurities such as dust, pet dander, or even bacteria from the air that flows through the system. Not only does this improve the air quality inside your home, but it also protects your HVAC system from potential damage. Air filters keep debris and air particles out of sensitive components. Two places where dust and dirt can accumulate are the duct system and the air handler.

Debris will build up over time creating a variety of problems, in addition to polluting indoor air. An air purifier will eliminate odors to a certain extent, but it all depends on the carbon inside the filter. Air filters are an aftermarket product with a longevity that typically lasts 1 to 6 months for disposable filters. Air purifiers usually consist of a filter, or several filters, and a fan that draws in and circulates the air. Research shows that filtering the air can help remove harmful particles from indoor spaces, especially allergens, smoke and mold. The longer technical guide focuses on air filters for residential use; it does not cover air filters used in large or commercial structures, such as office buildings, schools, large apartment buildings, or public buildings.

You can also look for air purifiers and filters that are certified asthma and allergy friendly devices from the Asthma and Allergy Foundation of America. Do-It-Yourself (DIY) air filters are indoor air filters that can be assembled from box fans and square HVAC (or oven) filters. Air purifiers can help clean the air in your home of unwanted particles, such as pet dander, allergens, and smoke. Air filters with a MERV rating of 14 or higher capture more particles, but they also restrict airflow more and clog faster. Using air filters alone cannot guarantee adequate air quality, especially when there are significant sources of pollutants and insufficient ventilation. An air cleaner is essentially a screen that fits in a compartment of the HVAC system to clean air as it circulates through a home.

Some air purifiers use ionizers to help attract particles such as static negative ions that bind to dust and allergens and cause them to be deposited out of the air. Before investing money in an air purifier, you should consider running an air quality test at home first to see if you need it. Portable air filters and HVAC filters can reduce indoor air pollution; however, they cannot remove all pollutants from the air.