Why Radon Levels Illinois Homeowners Should Test for Radon Levels Illinois
Understanding Radon in Illinois Homes
I have spent years working with homeowners across the Metro East area, from Belleville to Edwardsville to O'Fallon IL and Collinsville, and one question I hear more than any other is whether radon is really a problem here. The short answer is yes. Radon gas is a naturally occurring radioactive gas that comes from the decay of uranium in soil, and it can seep into homes through cracks in foundations, gaps around pipes, and other openings. Illinois has some of the highest radon levels in the country, partly because of the region's geology and partly because of how our homes are built. The EPA has classified much of Illinois as Zone 1, meaning the average indoor radon levels are expected to exceed the action level of 4 picocuries per liter (pCi/L). That is a serious concern for anyone living in the Metro East area.
I have tested homes in Belleville where the short-term radon test came back at 8 pCi/L, double the EPA action level. I have also seen homes in Edwardsville where a long-term radon test showed levels around 3 pCi/L, which is still above the safe threshold recommended by the National Radon Program. The key takeaway here is that radon levels vary from one house to the next, even on the same street. Soil composition, house construction, and ventilation all play a role. That is why I always tell homeowners that the only way to know your risk is to test. You cannot smell radon. You cannot see it. And it does not cause immediate symptoms. But over years of exposure, it is the second leading cause of lung cancer in the United States, according to the EPA.
When people ask me about radon levels Illinois, I explain that the state has a robust program through the IL Department of Public Health that provides resources and guidance for testing. But the responsibility falls on the homeowner. No one else is going to come to your door and offer to test your basement for free. If you live in the Metro East, you need to take action. I have seen too many families assume their home is fine because their neighbor tested low, only to find out their own radon levels were dangerously high. Radon does not follow a predictable pattern.
How Radon Testing Works
There are two main types of radon testing: short-term and long-term. A short-term radon test typically lasts two to seven days and gives you a quick snapshot of radon levels in your home. These are useful for initial screening, but they can be influenced by weather, ventilation, and recent changes in the home. A long-term radon test, which lasts 90 days to a year, provides a much more accurate picture of your average exposure. I always recommend starting with a short-term test, and if the result is above 4 pCi/L, follow up with a long-term test before making decisions about radon mitigation.
The radon detector itself is a simple device. It can be a charcoal canister, an alpha track detector, or an electronic monitor. You place it in the lowest livable area of your home, usually the basement or a first-floor room if you have no basement. You leave it undisturbed during the test period, then send it to a lab for analysis. Some electronic detectors give you a reading in real time, which can be helpful for seeing how radon levels fluctuate day to day. I have used all these methods in homes across O'Fallon IL and Collinsville, and each has its place. The important thing is to follow the instructions carefully. A test placed too close to a draft or in direct sunlight will give you a false reading.
Once you have your results, you need to compare them to the EPA action level. If your radon levels are above 4 pCi/L, the EPA recommends taking steps to reduce them. But even if your levels are between 2 and 4 pCi/L, you might still want to consider mitigation, especially if you have young children or spend a lot of time in the basement. The National Radon Program provides guidance on acceptable levels, and many experts agree that no level of radon is completely safe.
Radon Mitigation Options for Metro East Homes
If your radon levels Illinois test results come back high, the next step is radon mitigation. The most common and effective method for homes in the Metro East is sub-slab depressurization, also called soil suction. This involves drilling a small hole through the basement floor, inserting a pipe, and attaching a fan that creates negative pressure underneath the slab. The fan draws radon gas from the soil and vents it safely outside, above the roofline. It is a proven technique that works in most homes, but it does require a qualified installer. Air Sense Environmental has installed many of these systems in Belleville and Edwardsville, and I have seen them reduce radon levels from 10 pCi/L down to below 1 pCi/L.
Other mitigation options include sealing cracks and openings in the foundation, improving ventilation in the basement, and installing a heat recovery ventilator (HRV) to exchange indoor air with outdoor air. Sealing alone is rarely enough, because radon can still seep through porous concrete and around pipes. Sub-slab depressurization is usually the gold standard. But every home is different. The type of foundation, the soil type, and the layout of the house all affect which method will work best. That is why a professional assessment is so important.
I have worked with homeowners in O'Fallon IL who tried to fix their radon problem by themselves, using caulk and plastic sheeting, only to see their levels stay the same. Radon mitigation is not a DIY project for most people. The equipment is specialized, and the installation needs to be done correctly to ensure the system works and does not create other problems like backdrafting of combustion appliances. A qualified radon mitigation contractor will perform a post-mitigation test to confirm the system is working.
The Role of the IL Department of Public Health and National Radon Program
The IL Department of Public Health offers a radon measurement proficiency program and lists certified testers and mitigators. They also provide educational materials and sometimes low-cost test kits during Radon Action Month in January. The National Radon Program, run by the EPA and other federal agencies, sets the standards for testing and mitigation and funds research into radon health effects. Both organizations are valuable resources for homeowners. I always tell people to check with the IL Department of Public Health to find a certified professional, because using someone who is not certified can lead to bad data or poor mitigation work.
In the Metro East area, we are fortunate to have local experts who understand the specific geology and housing stock. Air Sense Environmental is one of the companies that provides both radon testing and radon mitigation services in Belleville, Edwardsville, O'Fallon IL, and Collinsville. They follow EPA guidelines and use calibrated equipment. I have seen their work firsthand, and it is thorough.
What You Should Do Next
If you have not tested your home for radon, now is the time. The EPA and the Surgeon General recommend that every home be tested, and homes in Zone 1 areas like most of Illinois should be tested at least every two years, or after any major renovation. If you have already tested and your radon levels Illinois were high, do not delay mitigation. The longer you wait, the more exposure accumulates.
I have seen families in Collinsville put off mitigation for years because they thought it was too expensive or too disruptive. But modern sub-slab depressurization systems are quiet, efficient, and often cost less than a new furnace. The peace of mind is worth it. And in many cases, the cost of mitigation is far less than the potential health care costs down the road. Radon is a preventable problem. Testing and mitigation are straightforward steps that every homeowner can take.
If you are buying a home in the Metro East, make radon testing part of your inspection. Ask for a short-term radon test to be done before closing. If the levels are high, you can negotiate with the seller to install a mitigation system. I have seen this done many times in Edwardsville and Belleville. It is a standard practice now. Do not skip it.
Radon is a serious health risk, but it is also a manageable one. With proper testing and the right mitigation system, you can protect your family. The first step is to understand what radon levels Illinois are in your home. Test today, breathe easier tomorrow.