What You Need To Know About IAQ

by Adam Mennenga and Jeff Sims

January 24, 2023

8:47 AM

“Americans, on average, spend approximately 90% of their time indoors, where the concentrations of some pollutants are often two to five times higher than typical outdoor concentrations.” - U.S. Environmental Protection Agency

Why it matters: Most of us spend about 90% of our time indoors. Indoor air quality (IAQ) is getting worse due to the increased use of synthetic building materials, personal care products, pesticides and household cleaners we all use. And then add in allergens and viruses.

So, what can you do? The best way to defeat any airborne contaminants is to zap them and trap them with a simple addition to your home’s central HVAC system – a whole-house air purifier, also called an air scrubber.

Most homes have traditional paper filters that remove only the biggest particles, but nothing as small as viruses less than one micron. The illustration here shows the relative sizes of common pollutants. NOTE: a micron is 1/25,000th of an inch!

Most home AC systems use paper filters one-to-four inches thick to trap airborne particles. Filter efficiency is rated by Minimum Efficiency Reporting Values (MERV) of 1-20. The higher the number, the more contaminants the filter removes.

HVAC equipment limitations: Your equipment determines the MERV value to use. Using a filter rated higher than your system was designed for will reduce the airflow, causing your HVAC to run longer and harder and wear out faster.

Newer home HVAC systems can use filters rated up to MERV 11 or 12. MERV 12 filters remove particles measuring 1-3 microns at 80% efficiency, but that drops to 35% for particles measuring 0.3-1 microns.

Commercial systems use MERV 13-16. A MERV 16 filter can trap 0.3–1 micron particulates at 95% efficiency.

Hospital-clean air: High-Efficiency Particulate Air (HEPA) filters (MERV 17-20) used in laboratories and medical facilities stop particulates as small as 0.3 microns more than 99% of the time. But the COVID-19 virus measures 0.1–1 microns – too small for a HEPA filter. HEPA filters are much more expensive than standard media filters.

UV light kills viruses: UV lights added to central HVAC systems can be effective against the COVID-19 virus, depending on the intensity of the bulbs and the length of time the virus is exposed to them as it passes through the air handler.

You can have cleanroom-quality air in your home without having to install an expensive commercial- or medical-grade HVAC system. Many whole-house air purifiers perform equal to or better than HEPA filters, but each has limitations.

Polarized Electronic Media Cleaners: Older electronic filtration systems electronically charge solid particles in the air as they pass through an HVAC system. Collection plates with the opposite charge attract and trap them after they are charged. These devices can remove sub-micron-size particles, including dust, pet dander, pathogens, smoke, cooking and chemical odors.

The main flaw is the rapid fall-off in efficiency as dirt builds up on the collection plates. They must be removed and cleaned with a hose frequently. Many of these units also produce harmful ozone and circulate it throughout the house.

UV Germicidal Lamps: Other systems use ultraviolet UVC lamps installed in an HVAC air handler to zap contaminants as they pass through, including viruses and germs. The concept is sound, but the implementation often falls short.

Their effectiveness depends on the strength of the UVC bulb(s), the distance of the particles from the UVC bulb and the speed of the air passing through the system. Some products – including popular brand names – have UVC bulbs with only a fraction of the wattage required to kill pathogens as they move quickly through air handlers.

Activated Carbon: Some systems, including media filters, use activated carbon to remove odors from smoke, damp or musty smells and pets. The carbon absorbs the tiny odor particles as they pass through it.

These systems effectively remove organic compounds from indoor air. However, they do not remove bacteria or viruses and fine particulate matter. Carbon filters are more expensive and require more frequent replacement.

Over the years, we have recommended and installed a number of whole-house air purifiers that have dramatically improved the indoor air quality of our customers’ homes. All of them are good products, a huge improvement over standard paper air filters.

Now, billyGO offers an IAQ solution that uses all three technologies for incredibly high performance:

To get the cleanest possible air in our home, ask us about the Dynamic RS4 Whole House IAQ System

923 Minters Chapel Rd., Grapevine, Texas 76051

Phone 817.722.6151

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by Adam Mennenga and Jeff Sims

January 24, 2023

8:47 AM