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Find Radon gas testers in Dupo

Avatar for STL Home Inspection Services
STL Home Inspection Services
4.9(
45
)

Serving Dupo, IL and surrounding areas

In business since 2008

Free estimates

Warranties offered

(Retired Air Force) We are a professional inspection company specializing in residential, radon, thermal, termite, and mold. Our team has over 30 years of combined experience.

Recommended by91%of homeowners
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Avatar for ENVIROPRO
ENVIROPRO
4.8(
13
)

Serving Dupo, IL and surrounding areas

In business since 2003

Free estimates

Warranties offered

Enviropro is an industrial hygiene and consulting company. We specialize in indoor environmental issues. We have over twenty years experience in the environmental consulting industry. We have provided expert witness testimony. Our clients include everyone from residential structures to commercial buildings to schools and universities. We have been featured on History Channel’s Modern Marvels. Our goal is to provide comprehensive information to our clients without resorting to scare tactics. We have some of the highest credentials available in the industry. We were also on the peer review board for the most current mold remediation guideline.

Recommended by92%of homeowners
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Avatar for Radon Professional Inspectors
Radon Professional Inspectors
4.6(
10
)

Serving Dupo, IL and surrounding areas

In business since 2009

Free estimates

Warranties offered

Radon Professional Inspectors is a complete radon company providing radon services for residential and commercial clients. RPI can test and mitigate any type of home you live in, or any type of building you work. You don't have to live with radon. Call Radon Professional Inspectors and breathe easy.

Recommended by90%of homeowners
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Avatar for Criterium - Hardy Engineers
Criterium - Hardy Engineers
5.0(
5
)

Serving Dupo, IL and surrounding areas

In business since 2003

Free estimates

Warranties offered

Criterium Hardy Engineers provides professional inspection, evaluation and diagnostic building services for the St. Louis Region including the cities of Chesterfield, Ballwin, Kirkwood, Manchester, Wildwood, St. Charles, O’Fallon, and Creve Coeur. Our Missouri and Illinois licensed Professional Engineers have experience with a wide variety of facilities types and building systems.

Recommended by100%of homeowners
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Waterproof-Solutions
4.2(
18
)

Serving Dupo, IL and surrounding areas

In business since 2009

Free estimates

Warranties offered

"I hired Waterproof Solutions in January 2022 to install an interior drain and sump on two walls ($5,000, lifetime warranty on treated walls). In June 2025, after an extremely wet spring in St. Louis, water entered through a wall they treated. The sump pit has been bone dry and the pump has never run since installation. I requested a refund, per the terms of the contract. On June 11, their representative said the company had changed ownership and would not honor the prior warranty. As of today, the issue remains unresolved. I will update this review if the company provides a fair resolution."
Recommended by72%of homeowners
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FAQs for radon gas testing projects in Dupo, IL

Radon is the second leading cause of lung cancer in the U.S. The gas seeps through cracks in foundations and collects in basements and other low areas. Once you breathe it in, radioactive particles lodge in lung tissue and do long-term damage. Because you can’t see or smell radon, the EPA recommends testing your home every two years—and after major renovations—to keep your family safe.

Yes—every home should be tested. The EPA advises doing it at least every two years and any time you remodel, buy, or sell. On average, one in 15 houses nationwide sits above the recommended limit, and the only way to know where yours stands is a formal test. The equipment simply measures gas levels and won’t change your indoor environment, so the process is completely harmless.

Certified radon professionals—often home inspectors or dedicated radon mitigation contractors—handle testing. These radon testing professionals follow EPA protocols and use calibrated instruments to check levels throughout your house. Hiring a certified radon specialist means results you can trust for real estate deals, insurance requirements, and, most importantly, your family’s health.

Inspectors specialize in measuring radon gas levels, while licensed mitigation contractors design and install the systems that remove it. If your test comes back high, your inspector can point you to a qualified mitigation pro who will size and install the right fan, piping, or other equipment to bring levels down.

No—standard home air purifiers don’t touch radon. They’re built to trap dust and pollen, not radioactive gas. If testing shows high levels, you’ll need a dedicated mitigation system that vents the gas from beneath your home to the outdoors. Relying on a room purifier alone won’t keep your indoor air safe.

Opening a few windows in your home might dilute radon for a short time, but the gas seeps back in as soon as they’re closed. For a lasting fix, you’ll need a professional mitigation system—often a sub-slab depressurization fan—that pulls radon from beneath the foundation and safely vents it outside.

The Dupo, IL homeowners’ guide to radon gas testings

From average costs to expert advice, get all the answers you need to get your job done.

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