Indoor Air Quality - How does it apply to my Home?

All of us face a variety of risks to our health as we go about our day-to-day lives. Driving in cars, flying in planes, engaging in recreational activities, and being exposed to environmental pollutants all pose varying degrees of risk. Some risks are simply unavoidable. Some we choose to accept because to do otherwise would restrict our ability to lead our lives the way we want. And still more are risks we might decide to avoid if we had the opportunity to make informed choices.

Did you know that the air inside your home is as much as nine times more toxic than the air outside your home?

What causes indoor air pollution?

The short answer: Everything!

Anything that releases gases or particles into the air inside your home is to blame for your poor indoor air quality. Inadequate ventilation can increase indoor pollutant levels by not bringing in enough outdoor air to dilute emissions from indoor sources. The same inadequate ventilation fails to carry indoor air pollutants out of the home. High temperature and humidity levels can also increase concentrations of some pollutants.

Some of the most common sources of poor indoor air quality include:


Amount of Ventillation

Newer homes are being built with a tighter and tighter "envelope" these days. The envelope of your house is defined as the exterior walls and roof of the home, or any part of the home that has direct contact with the outside. The rate at which air moves from the inside of the envelope to the outside is known as the "air exchange rate".

How does Outside air enter a house?

In older homes, with looser envelopes, outside air tended to enter a house in one of two ways. The first, infiltration, is the air that enters a house through spaces that were not intended; like in gaps under exterior doors, through unsealed penetrations to the outside, etc. The second is by an open window.

In newer homes, the goal in construction is to limit infiltration to zero, or near zero. But this goal actually hinders indoor air quality, by keeping the stagnant toxic air inside your home. Houses that are built this tight require mechanical ventilation.

Indoor Air Pollution and Health

Immediate Effects Long-Term Effects**
  • Irritation to eyes, nose, and throat
  • Headaches, Dizziness, Fatigue
  • Asthma
  • Respiratory Disease
  • Heart Disease
  • Cancer/Death

Improving Indoor Air Quality

Source Control

Typically the most effective way to control indoor air quality, and affect it for the better, is through controlling the points of access for air exchanges. You can do this by eliminating potentially dangerous materials, sealing visible cracks and gaps, and introducing new sources for air to exchange.

Improved Ventilation

The second approach to lowering the concentrations of indoor air quality is to simply give it an avenue to leave your home. The most common of these is the simple use of exhaust fans which most homes have already installed in high moisture areas such as bathrooms, kitchens (hood), and laundry rooms.

Air Cleaners

The last of the methods to contain indoor air quality problems is also the most controversial. For years, Ozone-producing products have been marketed to the general public as great Indoor Air Cleaners, but recently it has been determined that Ozone is actually very bad in your home. [Ozone-Generators Banned]. Ultimately, the most affective air cleaners require that the air be moving through the duct system. The problem this presents to a homeowner, you can hear the fan turning. This has presented as a large problem in our area, since our utility rate is so high, we’ve naturally learned to associate that fan with dollars out of our pockets.

Your best ally in the fight for good indoor air quality is your centralized duct system. You can filter the air in your home much more efficiently by simply cycling the air handler to move the air in your house through the various filters that are in place.

Additional ways to filter the air in your house would include stand-alone filtration systems. These stand-alone filtration systems do exactly what your air handler in your house does, only at a much slower rate, since the fan in a stand-alone box is typically very small.



** Further research is needed to better understand which health effects occur after exposure to the average pollutant concentrations found in homes and which occurs from the higher concentrations that occur for short periods of time.

All the above referenced information is provided by the Environmental Protection Agency (EPA) on their website.