Service Area · Ofallon, IL
Indoor Air Quality in O’Fallon, IL

An indoor air quality test in O’Fallon, IL is a 48-hour continuous monitoring assessment, not a spot check. Air Sense Environmental records particulates, VOCs, CO2, CO, temperature and humidity in O’Fallon homes at one-minute intervals and turns the data into a written report with specific fixes.
What does an indoor air quality test measure in a O’Fallon home?
- Particulate matter (PM2.5 and PM10) from cooking, candles, smoke and HVAC systems
- Chemical vapors (VOCs) from paints, cleaners, new flooring and furniture
- Carbon dioxide and carbon monoxide, which point to ventilation and combustion problems
- Temperature and relative humidity; sustained humidity above 60 percent is a warning sign
- Radon (optional), measured against the EPA action level of 4.0 pCi/L
When should O’Fallon homeowners test indoor air quality?
O’Fallon, Illinois grew quickly from the 1990s onward around Scott Air Force Base, so most of its housing is newer subdivision construction, which does not exempt it: tight, energy-efficient homes hold radon indoors longer than drafty older ones. These are the situations and O’Fallon home types where a test pays off:
- Allergy or respiratory symptoms that ease when you leave the house
- After a renovation, new flooring or new furniture
- Humidity that stays high, or a musty smell from a basement or crawl space
- Before buying or selling a home
- 1990s and 2000s two-story homes on poured basements in the subdivisions off Highway 50 and Green Mount Road
- Homes bought and sold on military timelines near Scott Air Force Base, where real estate testing is routine
How does indoor air quality testing work in O’Fallon?
- Monitor placement. One or more continuous monitors go in the rooms where the family spends its time.
- 48 hours of data. Readings are logged at one-minute intervals through normal daily life.
- Written report. You see each pollutant against its healthy range, with the specific fix for anything outside it.
What happens after the indoor air quality results?
The report names the problem, and Air Sense Environmental installs the fix it calls for: an AprilAire whole-home dehumidifier for high humidity, an energy recovery ventilator for stale air and rising CO2, or a radon mitigation system when radon is at or above 4.0 pCi/L. The main indoor air quality testing page covers the equipment and the full process.
How much does indoor air quality testing cost in O’Fallon, IL?
Pricing depends on the size of the O’Fallon home and how many monitoring locations it needs; most single-family homes need one or two monitors. Call 314-664-9807 for a free consultation and an exact quote.
O’Fallon neighborhoods and nearby communities
Air Sense Environmental works across O’Fallon, IL, including downtown O’Fallon, the Highway 50 corridor and the subdivisions between O’Fallon and Scott Air Force Base, in ZIP code 62269. Nearby communities with their own service pages:
- Air quality and radon services in Belleville, IL
- Air quality and radon services in Fairview Heights, IL
- Air quality and radon services in Swansea, IL
- Air quality and radon services in Troy, IL
- All Air Sense Environmental service areas
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