Radon in Illinois: What I Want Every Family to Know About the Air at Home

By Tracy, Owner of Quality Environmental Testing Inc.

After more than 20 years of radon testing, here is what I want people to understand: you do not have to be buying or selling a home for radon to matter.

The air you breathe matters every day you live there.

At Quality Environmental Testing, our family-owned business has served Southwest Chicagoland since 2002. My goal is to help people understand what a radon test tells them, why it matters, and what to do with the results.

Whether you live in a house, apartment, townhouse, or condo, you deserve answers about your home.

What is radon, and how does it get inside?

Radon is a naturally occurring radioactive gas produced as uranium breaks down in soil and rock. You cannot see, smell, or taste it.

Outside, it disperses into the air. Inside a building, it can accumulate.

It can enter through foundation cracks, sump pits, crawl spaces, construction joints, and gaps around pipes. A home does not need a large, visible foundation problem for radon to get inside. Illinois health officials identify several of these entry routes, and radon has been measured in buildings with different foundation types.

That is why I encourage people to test rather than judge a home by how it looks. A beautiful, well-maintained home can still have elevated radon.

How does radon affect your health?

When radon breaks down, it produces radioactive particles that can be inhaled. Those particles can damage cells lining the lungs. Over time, that damage can lead to lung cancer.

Radon is the second leading cause of lung cancer in the United States and the leading cause among people who do not smoke. Smoking combined with radon exposure increases the risk further.

This is a long-term exposure concern. You cannot depend on how you feel to tell you whether your home has elevated radon.

I want families to take it seriously without feeling helpless. Testing gives you information, and elevated levels can be reduced.

Does radon matter for children and everyone else in the home?

Yes. Radon deserves attention whether the people living there are children, working adults, or retirees.

The level of radon and the amount of time spent breathing it both matter. Think about where your family spends time: a basement playroom, a downstairs bedroom, a home office, or a favorite television room.

Children may inhale a different dose than adults because of differences in breathing rates and lung size. However, CDC says there is not enough information to establish whether children have a greater risk of developing radon-related lung cancer than adults.

We do not need to exaggerate the science to make the point: reducing avoidable exposure is worthwhile for the whole household.

What about dogs, cats, and other pets?

Our pets share our homes and breathe the same air.

An indoor cat or a dog that stays home while everyone is at work may spend many hours in the building. Pets belong in the conversation about radon exposure, too.

Public-health guidance recognizes radon as a potential concern for pets. However, research on household pets is more limited than the evidence in people. Human lung cancer risk charts should not be used to predict a particular dog’s or cat’s risk.

My advice is practical: include your pets when you think about the spaces your household uses, and address elevated radon in the building. You cannot identify a radon problem by watching your pet for symptoms.

Houses, apartments, townhouses, and condos all deserve attention

Radon does not stop being a concern because you share walls or rent instead of own.

A townhouse can have a basement, crawl space, or slab foundation. Apartments and condos can have ground-contact living spaces and pathways that allow air to move through a building.

Lower floors often have higher radon levels, but living upstairs is not a guarantee of low levels. Illinois recommends testing all residences and notes that elevated levels have sometimes been found on upper floors.

For a condo or apartment, ask about testing that applies to your unit. A result from another unit or a shared area does not automatically establish the level where you live.

If building-wide testing or repairs are needed, the owner, property manager, or association may need to coordinate the work.

Your neighbor’s result does not tell you your result

Homes next door to each other can have different radon levels. Soil conditions, construction, and the pathways radon takes into a building all affect the result.

Illinois has identified elevated radon throughout the state. Its radon map is useful background information, but the state specifically warns against using the map to decide whether an individual home needs testing.

Whether you live in Lockport, Lemont, Homer Glen, New Lenox, or another nearby community, the answer comes from testing your home.

What happens during a professional radon test?

At QET, we use continuous radon monitors for a 48-hour test. The monitor records hourly readings, which are used to evaluate the average radon level during the measurement period.

Proper placement matters. Illinois real estate guidance calls for testing each lowest structural area suitable for occupancy. Depending on the layout, a home may need more than one monitor.

Preparation matters, too. For a typical 48-hour test, Illinois requires closed-building conditions beginning at least 12 hours before testing and continuing throughout the measurement. Windows stay closed, and exterior doors are used for normal entry and exit. We explain the additional instructions for your property before testing.

You can generally remain at home during the test. Leave the equipment in place and follow the instructions so the measurement is valid.

After the test is completed and reviewed, QET provides an electronic report and helps you understand the results.

What does your radon number mean?

Radon is measured in picocuries per liter of air, written as pCi/L.

EPA recommends:

• 4.0 pCi/L or higher: Take action to reduce radon.

• Between 2.0 and 4.0 pCi/L: Consider reducing radon.

• Below 2.0 pCi/L: Lower exposure is preferable, but no result establishes zero risk.

The important distinction is that 4.0 is an action level. It is not a dividing line where risk suddenly begins. EPA states there is no known safe level of radon exposure.

A short-term test measures conditions during that period. Levels can change with weather and seasons; a long-term test lasting more than 90 days gives a better indication of the year-round average. Follow-up recommendations depend on your result and whether the test is for a real estate transaction or ongoing household exposure.

What if your result is elevated?

An elevated result gives you something you can address.

A licensed Illinois radon mitigation professional can evaluate the building and recommend a reduction system. Many systems use a pipe and fan to draw soil gas from beneath the building and discharge it outdoors. Testing afterward confirms whether the system reduced the level.

QET is a testing-only company. We do not install mitigation systems. Our role is to provide independent measurements and help you understand the findings.

If you rent, ask about radon

Illinois has specific radon disclosure requirements for rental units below the third story. These include a tenant guide, a disclosure form, and available records indicating a radon hazard.

State guidance also describes a 90-day testing opportunity at the beginning of the agreed leasing period and requires tenants who test to provide results to the landlord within 10 days of receiving them. Other procedures and deadlines apply when elevated levels are found. Review current state guidance before making a lease decision.

The practical starting point is simple: ask what testing has been done and whether the results apply to your unit.

Do not let an old test be your last test

A radon result is useful information about a particular measurement period. It is not a lifetime guarantee.

Illinois health guidance recommends testing every two years. Renovations, additions, and changes to how lower-level rooms are used are also good reasons to discuss retesting.

If you have finished a basement for sleeping, working, or family time, make radon part of that planning.

You deserve to know what you are breathing

After more than two decades in this business, my message is straightforward: do not wait for a move to learn about radon.

Your home is where your family sleeps, gathers, works, and spends time with the pets you love. Understanding radon is part of caring for that home.

If you have never tested, cannot find your previous results, or need help understanding a report, contact Quality Environmental Testing. We serve Lockport and surrounding Southwest Chicagoland communities with professional radon testing and clear explanations.

Let’s find out what the level is in your home—and take the next step from there.