Radon is one of those things most homeowners don’t think about until they hear the word during a real estate transaction or news segment. The tricky part is that radon exposure doesn’t cause obvious, immediate symptoms.
You won’t smell it, taste it, or feel sick right away, but this invisible, odorless gas is the second leading cause of lung cancer in the United States, responsible for about 21,000 deaths each year, according to the EPA.
Here’s what you need to know about radon, your home, and your health.
What Is Radon and Where Does It Come From?
Radon is a naturally occurring radioactive gas produced when uranium in soil, rock, and water breaks down. It seeps up through the ground and can enter your home through cracks in the foundation, gaps around pipes, sump pumps, and other openings.
Every home has some level of radon. The question is whether your levels are high enough to pose a health risk. In North Carolina, certain geological conditions make elevated radon levels more common than many residents realize.
Homes throughout Charlotte and surrounding communities can have significantly different radon levels even on the same street.
The gas accumulates in enclosed spaces, especially lower levels like basements and ground-floor rooms, where many families spend significant time. Without radon testing, there’s simply no way to know what you’re breathing.
Does Radon Exposure Cause Immediate Symptoms?
This is where radon differs from other household hazards. Carbon monoxide causes headaches and nausea. Mold triggers allergies and respiratory irritation. But radon exposure produces no immediate warning signs.
You won’t experience:
- Headaches or dizziness
- Nausea or fatigue
- Skin irritation or rashes
- Respiratory discomfort right away
This absence of acute symptoms is precisely why radon is called a “silent killer.” Your body doesn’t alert you to the danger the way it would with smoke, gas leaks, or contaminated food.
You can live in a home with dangerous radon levels for years without feeling anything unusual. The damage happens at the cellular level over time, which is why long-term exposure is what matters most.
Long-Term Health Effects of Radon Exposure
While radon doesn’t cause immediate symptoms, prolonged exposure to elevated levels significantly increases your risk of developing lung cancer.
When you breathe in radon, radioactive particles get trapped in your lungs. Over time, these particles damage lung tissue and can lead to cancer.
Risk factors that increase danger:
| Factor | How It Affects Risk |
| Higher radon levels | More hours indoors mean more exposure |
| Longer exposure time | Years of accumulated lung damage |
| Smoking history | Radon + smoking multiplies lung cancer risk dramatically |
| Time spent at home | More hours indoors means more exposure |
| Living areas on lower floors | Ground-level rooms typically have higher concentrations |
The EPA estimates that radon causes more lung cancer deaths than drunk driving. For smokers, the combination of radon exposure and tobacco use creates a risk factor far greater than either hazard alone.
Non-smokers aren’t immune, though. Radon is the leading cause of lung cancer among people who have never smoked. Symptoms of radon-related lung cancer typically don’t appear until the disease has progressed.
These can include persistent cough, shortness of breath, chest pain, coughing up blood, frequent respiratory infections, and unexplained weight loss. By the time these symptoms appear, the cancer may be advanced.
What Radon Levels Are Dangerous?
Radon is measured in picocuries per liter (pCi/L). The EPA has established guidelines to help homeowners understand their risk:
- Below 2 pCi/L: Low risk, though no level is completely safe
- 2 to 4 pCi/L: Consider mitigation to reduce levels
- 4 pCi/L and above: EPA recommends taking action to reduce radon
- Above 8 pCi/L: Higher urgency for mitigation
The average indoor radon level in the U.S. is about 1.3 pCi/L, while outdoor air averages around 0.4 pCi/L. Many Charlotte-area homes test well above the 4 pCi/L action level, particularly those built on certain soil types or with specific foundation characteristics.
It’s worth noting that the World Health Organization recommends action at even lower levels than the EPA, suggesting 2.7 pCi/L as a threshold. The bottom line is that lower is always better when it comes to radon.
Why Testing Is the Only Way to Know Your Risk
Since radon produces no symptoms, smells, or visible signs, testing is the only reliable way to determine your exposure level.
You can’t predict radon levels based on your neighbor’s results, your home’s age, or construction type. Two identical homes next door to each other can have drastically different readings.
When to test for radon:
- Before buying a home in the Charlotte area
- If you’ve never tested your current home
- After major renovations, especially to the foundation or basement
- After installing a mitigation system to verify it’s working
- Every two to five years, as conditions can change
Short-term tests take two to seven days and provide a snapshot of your radon levels. Long-term tests run for 90 days or more and give a more accurate picture of year-round exposure. For real estate transactions, short-term tests are typically used due to time constraints.
Professional radon testing provides the most accurate results. Certified inspectors know proper placement, timing, and protocols to ensure reliable readings. DIY kits are available, but can produce inconsistent results if not used correctly.
What to Do If Your Home Has High Radon
Elevated radon levels don’t mean you need to abandon your home. Radon mitigation systems are effective, well-established, and typically affordable. Most systems can reduce radon levels by up to 99%.
The most common solution is a sub-slab depressurization system, which uses a pipe and fan to draw radon from beneath your foundation and vent it safely outside. Installation usually takes less than a day, and the system runs quietly and continuously.
After mitigation, follow-up testing confirms the system is working properly. Most homeowners see their levels drop well below the 4 pCi/L threshold.
If you’re buying a home with elevated radon, you can negotiate for the seller to install mitigation or provide a credit toward installation costs. Either way, high radon shouldn’t necessarily be a deal-breaker since it’s a solvable problem.
Other Related Questions
What other air quality concerns should I test for?
Beyond radon, indoor air quality can be affected by mold, carbon monoxide, and volatile organic compounds (VOCs). Homes with moisture issues, older HVAC systems, or recent renovations may benefit from comprehensive air quality assessments.
Should I get a radon test before buying a home?
Yes. Radon testing is a smart addition to any pre-purchase home inspection, especially for homes with basements or crawl spaces. Knowing radon levels before closing gives you negotiating power and helps you budget for mitigation if needed.
What’s included in a standard home inspection?
A home inspection evaluates major systems, including roofing, electrical, plumbing, HVAC, and structural components. Radon testing, mold assessments, and other specialized services are typically offered separately to provide a complete picture of a property’s condition.
How does foundation type affect radon levels?
Homes with basements and crawl spaces often have higher radon concentrations than slab-on-grade construction, though any foundation type can allow radon entry. Cracks, gaps around pipes, and sump pits provide pathways for the gas to enter living spaces.
When to Call a Professional
Consider professional radon testing if:
- You’re buying or selling a home in the Charlotte area
- You’ve never had your home tested
- Your home has a basement or crawl space foundation
- You’ve completed major foundation work or renovations
- Previous tests showed borderline levels
- You want peace of mind about your family’s air quality
Testing is quick, non-invasive, and provides answers you simply can’t get any other way. Given that radon exposure causes no warning symptoms, testing truly is the only path to protecting your household.
Conclusion
Radon exposure won’t make you feel sick today or tomorrow. That’s what makes it so dangerous. The symptoms of radon-related illness only appear after years of cellular damage, often when lung cancer has already developed.
Whether you’re buying a new home, selling your current property, or simply want a complete picture of your home’s condition, professional inspections give you the information you need to make confident decisions.
AHI Residential & Commercial Inspections provides professional home inspections and radon testing throughout Charlotte and surrounding communities. Our certified inspectors deliver accurate, reliable results you can trust.