Radon Testing & Mitigation in Arnold, MO

In Arnold, MO, Air Sense Environmental tests homes for radon, installs radon mitigation systems, tests indoor air quality and encapsulates crawl spaces. Every radon job in Jefferson County is measured against the EPA action level of 4.0 pCi/L, and the team is NRPP-certified and IEMA-licensed (#RNM20232346).

Is radon a problem in Arnold, MO?

Yes. Jefferson County is in EPA Radon Zone 2, where the predicted average indoor radon level is 2 to 4 pCi/L, and individual Arnold homes routinely test well above the 4.0 pCi/L action level. Missouri’s Department of Health and Senior Services reports that roughly one in three homes tested through its statewide program between 2003 and 2023 came back at or above 4.0 pCi/L. Arnold sits where the Meramec River meets the Mississippi in northern Jefferson County, with 1960s to 1990s subdivisions on hilly, rocky ground and walkout basements cut into the slopes.

A Arnold neighbor’s reading is a signal, not an answer. The soil under one lot, the cracks in one slab and the way one sump pit was sealed decide the number, which is why two similar homes a few doors apart can land on opposite sides of the action level.

Radon testing in Arnold, MO

A Arnold radon test runs 48 hours under closed-house conditions on a calibrated continuous monitor, and the report shows the hourly data as well as the average. The St. Louis radon testing page covers how the test works, and the radon testing cost guide holds current pricing.

Radon mitigation in Arnold, MO

When a Arnold home tests at or above 4.0 pCi/L, the same team designs and installs the radon mitigation system, usually in a single day, and retests to confirm the home is below the action level. See the St. Louis radon mitigation services page for the process, documented results and warranty.

Indoor air quality testing in Arnold, MO

An indoor air quality assessment for a Arnold home logs particulate matter, chemical vapors, CO2, CO and humidity at one-minute intervals for 48 hours or more, so the fix is based on data. Details are on the St. Louis indoor air quality testing page.

Crawl space encapsulation in Arnold, MO

For Arnold homes with a crawl space, encapsulation lays a sealed vapor barrier over the soil and walls and adds humidity control, keeping damp air and soil gas out of the rooms above. Read more on the St. Louis crawl space encapsulation page.

Which Arnold homes does Air Sense Environmental work on?

The Arnold homes the team sees most often:

• 1960s to 1990s subdivision homes with full or walkout basements
• Hillside homes where part of the lower level is below grade
• Homes near the Meramec River bottoms with crawl spaces
• Newer homes on poured basements off Jeffco Boulevard

What should Arnold homeowners expect?

1. Test first. A 48-hour continuous monitor test gives the number everything else depends on.
2. Read the report together. You get the hourly data and a plain explanation of what it means for the house.
3. Design the fix. If the reading is at or above 4.0 pCi/L, the system is designed around your foundation during a free in-home estimate.
4. Install and verify. Most systems go in within a single day, and a post-mitigation test confirms the result.

Arnold neighborhoods and nearby communities

Air Sense Environmental works across Arnold, MO, including the Jeffco Boulevard corridor, the neighborhoods near Arnold City Park and the Meramec River bottoms, in ZIP code 63010. Nearby communities with their own service pages:

• Radon testing and mitigation in Oakville, MO
• Radon testing and mitigation in Fenton, MO
• Radon testing and mitigation in Festus, MO
• Radon testing and mitigation in Affton, MO
• All Air Sense Environmental service areas

From Our Work