About Radon
Understand the risk. Know the numbers. Take the right next step.
Radon is a naturally occurring radioactive gas that comes from soil, rock, and groundwater. You can’t see, taste, or smell it, and it can build up inside homes, especially in lower areas, without any warning signs. The only way to know your radon level is to test. If your results are high, a mitigation system can safely vent the gas outside, and follow-up testing will confirm that levels have dropped.
What Radon Is & Why It Matters
Radon forms naturally when uranium in soil and rock breaks down. It moves up through the ground and can enter your home through small openings. Once inside, it tends to build up in lower areas.
It’s everywhere (and any home can have it).
Radon is found throughout the US in every kind of home, whether old or new, tightly sealed or drafty, with basements, slabs, or crawlspaces. Your neighbor’s test result won’t tell you about your own home, since even houses on the same street can have very different levels.
Why Radon Matters in Indiana.
Elevated radon can be found in all 92 Indiana counties, and about 1/3 of homes here test at or above the EPA action level. Because of our glacial and clay soils and long heating season, more air is pulled from below ground into living spaces. This means any home, whether it has a basement, slab, or crawlspace, can have high radon levels. The only way to know is to test.
Common entry points
- Hairline slab or block-wall cracks
- The joint where the wall meets the floor (cove joint)
- Gaps around utility penetrations
- Unsealed or vented sump basins
- Exposed soil in crawlspaces
How we measure it
Indoor radon is measured in picocuries per liter (pCi/L). The EPA recommends fixing your home if levels reach 4.0 pCi/L, and suggests considering action if levels are between 2.0 and 4.0 pCi/L. Since radon levels can vary significantly from home to home and throughout the year, testing is the only way to determine your level accurately.
Ready to check your home? We can test for radon levels. If elevated levels are found, you’ll receive a tailored plan for Radon Mitigation, followed by a post-test to confirm its effectiveness.
How Radon Moves
Stack Effect, Seasons, and Closed-House Conditions
Homes “breathe.” As warm air rises and leaves near the top of the house, it pulls in air from below. This process, called the stack effect, can bring soil gases, including radon, into basements and crawlspaces. During colder months, when windows stay closed and the stack effect is stronger, radon levels are often higher. That’s why short-term tests are done with windows and doors closed, and why it’s wise to re-test over time.
A Brief History of Radon Awareness & Mitigation
People have noticed the effects of radon for centuries. For example, miners in the 1500s tried to ventilate mine shafts long before the term ‘radon’ was introduced in 1899. Awareness of indoor radon risks grew quickly in the late 20th century. By the 1970s, research and early mitigation efforts had started. In the 1980s, a highly publicized case of extreme home exposure brought national attention to residential testing. Since then, standards have focused on active sub-slab depressurization (SSD) and sub-membrane depressurization (SMD) for crawlspaces. These quiet, fan-powered systems gently pull soil gases from under the slab or a sealed crawlspace membrane and vent them safely above the roof.
Health Basics: Why Levels Matter
Radon gas is hazardous.
When you breathe indoor air with elevated radon, it decays into tiny radioactive particles that cling to dust and lodge in the lungs, where their radiation damages tissue over time and raises lung cancer risk.
What this means for your family:
A Cause of Lung Cancer
Second-leading cause of lung cancer in the US and the leading cause among non-smokers.
Risk adds up over time
The higher your radon number (pCi/L) and the more time you spend at home, especially in lower areas, the greater your lifetime risk.
Smoking multiplies risk
Radon + tobacco smoke is far more dangerous than either alone.
No Early Warning Signs
Most people have no symptoms from exposure, and illness often shows up years later. This is another reason why testing is so important.
Lower Levels Are Better
There is no known safe amount of radon exposure. The goal is to minimize exposure and check again periodically.
Testing 101
Stack Effect, Seasons, and Closed-House Conditions
Radon levels can vary from one house to another and even from season to season. Testing gives you a clear number so you can make an informed choice.
Where to test
- Test the lowest level of your home that you use now or might finish in the future. If you spend time in the basement, test there. If not, test the main floor.
- Put the test device in a living area, but avoid kitchens, bathrooms, laundry rooms, furnace rooms, or spots right next to a sump or outside door.
- Keep the device away from drafts and direct sunlight. Follow the instructions for how far off the ground and from walls it should be.
Closed-house conditions are important for accuracy
- For short-term tests, keep windows closed and exterior doors opened only for normal entry/exit for 12 hours before and during the test.
- Run your HVAC normally; don't use whole-house fans or attic fans.
Choose your test type
- Short-term tests (48 to 96 hours) give you a quick snapshot. You can use a professional monitor or a DIY charcoal canister. These are good for fast answers or real estate needs.
- Long-term tests (90 days or more) average out daily changes and give a clearer picture across different seasons. These are best if your first results are close to the action level.
- Professional testing uses calibrated equipment, tracks the test process, and provides a lab report. This is helpful for making decisions and keeping records.
Remember: there’s no such thing as a “false positive” radon test. Elevated numbers should be confirmed and addressed, not ignored.
How to read your result
- Under 2.0 pCi/L: Great result. Write down your result and test again every 2 to 3 years, or after large changes like renovations or HVAC work.
- 2.0-3.9 pCi/L: Think about taking action. Talk about your options with a radon mitigation specialist and confirm with a long-term test or another short-term test in a different season.
- At or over 4.0 pCi/L (EPA action level): It is time to fix your problem. Speak to a radon mitigation specialist to install a system in your home and test again to make sure levels go down.
When to re-test
- After installing a mitigation system (post-test is standard).
- Every 2–3 years as a checkup.
- After renovations, foundation changes, or HVAC updates.
- If you mostly tested in one season (e.g., winter), consider a second test in another season.
Take Your Next Step
Homes at Risk (It's Not Just Basements)
Any house. Any foundation. Any age.
Radon can get into any house, no matter its age or foundation type. It moves up from the soil and finds its way in through small gaps, whether your home has a basement, slab, or crawlspace.
- Basement: slab/wall hairline cracks, the wall–floor (cove) joint, and unsealed/vented sumps.
- Crawlspace: exposed soil and leaky rim joists draw soil gases into the home.
- Slab-on-grade: hairline slab cracks and utility penetrations allow entry.
Myth vs. Fact
Radon can seem confusing because of some common misconceptions. Here’s what Indiana homeowners need to know, in simple terms.
Myth: “Radon is only a basement problem.”
Fact: Any type of foundation can have high radon levels, whether it’s a basement, slab, or crawlspace. Radon moves up from the soil through small openings.
Myth: “We’re not in a ‘hot spot’ county.”
Fact: High radon levels can be found anywhere in Indiana. Testing is the only way to know your home’s level.
Myth: “New, energy-efficient homes don’t have radon.”
Fact: Well-sealed homes can actually trap more radon because they let in less fresh air.
Myth: “My neighbor tested low, I’m fine.”
Fact: Two houses right next to each other can have very different radon levels. The only way to know your level is to test.
Myth: “Below 4.0 pCi/L means no risk.”
Fact: There is no known safe level of radon exposure. The EPA recommends fixing at 4.0 pCi/L and considering action between 2.0-4.0 pCi/L to reduce exposure over time.
Myth: “I’ll crack windows and call it good.”
Fact: Open windows can lower radon levels for a while, but it’s not a real solution.
Myth: “Mitigation systems are loud, ugly, and expensive to run.”
Fact: Today’s sub-slab and sub-membrane systems are quiet, routed neatly, and use very little power. After installation, a follow-up test will confirm that radon levels have dropped.
Myth: “I don’t smoke, so radon isn’t a concern.”
Fact: Radon is the top cause of lung cancer from non-smokers and the second leading cause overall. Lowering radon levels helps protect everyone’s health.
Frequently Asked Questions
Have Radon questions before you test? Start here with the questions we hear most from Indiana homeowners.
What is radon?
Radon is a radioactive gas that is colorless, odorless, and tasteless. It forms naturally when uranium breaks down in soil, rock, and water. You can only detect it with a test.
Why is radon a health concern?
The EPA warns that radon is the second leading cause of lung cancer in the country.
What level of radon is "too high?"
There is no completely safe level, but the EPA recommends fixing homes at 4.0 pCi/L or higher. You should also consider action if your levels are between 2.0 and 4.0 pCi/L.
What's a "pCi/L?"
How common are high radon levels?
Where should I place a test in my home?
Short-term vs. long-term tests - what's the difference?
If my result is below 2.0 pCi/L, what should I do?
If my result is 4.0 pCi/L or higher, what next?
How often should I re-test?
Can water add radon to my home’s air?
What are radon-resistant features in new construction?
Didn’t see your question here? Ask our team and get a clear, no-pressure answer.
Glossary
Testing Terms
Mitigation Terms
Home & Building Terms
Know Your Number. Breathe Easier.
Not sure where your home stands? Start with a test. If levels are high, we’ll help you understand options and confirm results after the fix.
