Many owners of green homes are concerned about indoor air quality. GBA often receives questions from homeowners who worry that some building materials emit dangerous chemicals. For example:
We do our best to provide answers to these questions. But if there is a theme running through these questions — and I think there is — it would be this: homeowners are worrying about the wrong materials and substances.
Indoor air quality (IAQ) is a big topic. To get a handle on it, we need to break it down into small bites.
Here’s how I’d like to proceed:
Finally, I’ll share researchers’ findings about which chemicals are most concerning.
In most U.S. locations, indoor air is more polluted than outdoor air. According to the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), “Studies from the Environmental Protection Agency on human exposure to air pollutants show that indoor levels of pollutants may be two to five times, sometimes more than 100 times, higher than outdoor levels.”
There are exceptions to this rule, of course. If your house is located near a busy intersection or a location where buses or trucks often idle their engines, the outdoor air near you house may be more polluted than your indoor air. If you live in such a location, increased ventilation may not improve the quality of your indoor air. For the rest of us, however, ventilating a house with outdoor air usually improves the situation.
The most important test you should perform is a radon test. If you’ve tested for radon, you’re done. In most cases, further testing isn’t justified.
For more information on testing, see “Indoor Air Quality Testing Should Not Be The First Move.”
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