Top-rated radon gas testers.

Get matched with top radon gas testers in Longmont, CO

Enter your zip and get matched with up to 3 pros

Matching on HomeAdvisor

Share some details icon
Share some details about your home project.
Match with local pros icon
Within moments, match with highly-rated local pros.
Compare quotes icon
Compare quotes and choose the best pro for the job.

Find Radon gas testers in Longmont

Avatar for Lifetime Radon Solutions, Inc.
Lifetime Radon Solutions, Inc.
4.9(
120
)

Serving Longmont, CO and surrounding areas

Angi Approved

In business since 1993

Free estimates

Warranties offered

"Everyone I worked with was professional and answered all my questions. installation looks good. I have an Airthings continuous radon sensor. My radon was averaging 7 before. It is at 1.7 now."
Response time6 hrs
Response rate96%
86 neighbors recently requested a quote
Avatar for All Colorado Radon Mitigation Inc
All Colorado Radon Mitigation Inc
5.0(
38
)

Serving Longmont, CO and surrounding areas

Angi Approved

In business since 2012

Free estimates

Warranties offered

"All Colorado Radon Mitigation, Inc. is an incredible company to work with. They perform quality work, and they are truly friendly and professional. The system that they installed was straightforward, but the work was top-notch. Highly recommend!"
Basic Exterior System Pictures
Basic Exterior System Pictures
Basic Exterior System Pictures
Basic Exterior System Pictures
Additional Photos

+1

Response time2 days
Response rate95%
1 neighbors recently requested a quote
Avatar for Northern Colorado Radon, LLC
Northern Colorado Radon, LLC
5.0(
21
)

Serving Longmont, CO and surrounding areas

Angi Approved

In business since 2022

Free estimates

Emergency services offered

"Aarmond installed a radon abatement system in my house. He brought my radon level from 14 pCi/L to less than 4. He is very professional and I heartily recommend his company."
Single Color Paint Radon Install
Garage Install
Downspout Gutter
Two Paint Colors
Garage Attic Install

+18

Response time2 hrs
Response rate99%
Recommended by95%of homeowners
Avatar for PowerHouse Home Performance
PowerHouse Home Performance
5.0(
8
)

Serving Longmont, CO and surrounding areas

Angi Approved

Super Service Award Winner

In business since 2025

Free estimates

Warranties offered

"I can't say enough about Josh, our service man. He was on time an finished the job to our satifaction. He would be the one to call on any radon probleml To any one who has a radon problsem he is the one to call!!!! Tom"
Mitigation System
Vapor Barrier
Mitigation System
Mitigation System
Mitigation System

+1

Response time1 day
Response rate92%
3 neighbors recently requested a quote
Avatar for RCPI Residential Commercial Property Inspections
RCPI Residential Commercial Property Inspections
5.0(
85
)

Serving Longmont, CO and surrounding areas

In business since 2014

Free estimates

Emergency services offered

"Nate did an excellent and thorough job, finding important laws that compromised safety as well as cosmetic imperfections which could be improved.. he also took all the time needed to explain his findings verbally as well as in his extensive and detailed report.. he even suggested ways to increase the safety and efficiency regarding repairs. So very thorough and trustworthy!"
Recommended by98%of homeowners
Avatar for A Neeley Home Inspection Services
A Neeley Home Inspection Services
5.0(
52
)

Serving Longmont, CO and surrounding areas

Free estimates

Emergency services offered

Credit card accepted

"Andrew's service was nothing short of superb. From the moment he arrived to the time he left, his professionalism was evident. His attention to cleanliness during the inspection was greatly appreciated, and his thoroughness in examining every aspect of our new home provided us with invaluable peace of mind. Andrew's ability to explain technical details in simpler terms was a game-changer, ensuring we fully understood all the findings. He worked collaboratively with us and our realtor, playing a crucial role in negotiations to ensure our home was in the best shape possible. What truly stood out was Andrew's dedication; he even returned for a complimentary follow-up inspection after the sellers addressed the issues he had identified. This level of commitment and care is rare and deeply appreciated. We have now been in our home for a year and have enjoyed a trouble-free living experience, thanks to Andrew's thoroughness and invaluable advice."
Additional Photos
Additional Photos
Additional Photos
Additional Photos
Additional Photos

+71

Recommended by100%of homeowners
...
Showing 1-10 of 130
FAQs for radon gas testing projects in Longmont, CO

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 Longmont, CO homeowners’ guide to radon gas testings

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