Skip to content
RADON411

Radon professionals in Illinois

Who tests and fixes radon in Illinois, what Illinois's own program says about licensing, and how to check a credential before you hire.

Updated October 2, 2026

Illinois at a glance

  • Businesses listed

    337

    2nd of 20 states

    Illinois
    337
    Ohio
    478

    On Illinois's own list, or claimed there

  • Listed for testing

    266

    79% of listings

    Testing
    266
    Mitigation
    89

    5 laboratories listed as well

  • State license on file

    337

    100% of listings

    State license
    337
    NRPP
    1

    As each issuer's own record shows it

  • Share at 4+ pCi/L

    37.8%

    2.8 pts above U.S.

    Illinois
    37.8%
    U.S.
    34.9%

    187,881 tests across 98 counties, 2014

  • Counties in EPA Zone 1

    56 of 102

    Most at highest potential

    Zone 1
    56
    Zone 2
    43

    EPA's predicted potential; Zone 1 is the highest

Radon professionals listed for Illinois

337 professionals in Illinois. Showing 1 to 1224.

On this page: 1 testing and mitigation, 6 mitigation, 517 testing

Testing and mitigation 1

Mitigation 6

Testing 517

Show 12 more on this page

Located in Illinois, licensed by another state

These businesses have an address in Illinois, and another state's registry lists them. That does not mean Illinois licenses them: check with Illinois's radon program before hiring one for work here.

2 professionals located in Illinois and listed by another state.

By city

The 12 of 183 Illinois cities with the most listings. Search for any other, or open the full list.

View all 183 cities in Illinois
Every radon business listed in Illinois, A to Z (306)

Short answer

Radon professionals in Illinois, in brief

Radon411 lists 337 radon businesses for Illinois: 266 listed for radon measurement (testing), 89 for mitigation, 18 of them for both and 5 laboratories. Illinois's radon program says the state licenses or certifies radon professionals.

Radon levels

Read a radon result for Illinois

Before you call a professional: what EPA says about a test result, beside Illinois's own share of high tests.

Read a result for Illinois

Starts at EPA's action level

4.0pCi/L

EPA’s own thresholds; the figures are the area’s, never this home’s.

EPA’s reading of 4.0 pCi/L

At or above 4 pCi/L

  1. Under 20 to 1.9 pCi/L
  2. 2 to 4consider a fix
  3. 4 and aboveEPA says fix it

This result is at or above 4 pCi/L. EPA recommends fixing a home when the radon level is 4 pCi/L or higher. 37.8% of Illinois's reported tests reached 4 pCi/L, 2014.

Interpret this readingWhat a fix costs

Radon levels in Illinois, county by county

The rule

Does Illinois license radon professionals?

Yes. Illinois's radon program page, checked on November 3, 2026, says:

The Agency also licenses and regulates the individuals who provide radon measurement and mitigation to the public.
IEMA-OHS Radon Program, read November 3, 2026

EPA's state contacts page lists Illinois among the states with radon credentialing programs. Licensing is done by the state, not by the national programs, and EPA requires states that receive radon grants to give the public a list of only those providers credentialed by the state or by NRPP or NRSB.

Listings for Illinois come from the list of licensed radon professionals that the Illinois Emergency Management Agency (IEMA) publishes, last read on November 11, 2026, and from businesses that confirm their own details through Radon411's claim process.

State program

Illinois's radon program

The state's own radon program: the place to ask who may work in the state.

IEMA-OHS Radon Program

Illinois Emergency Management Agency and Office of Homeland Security

Its page covers who may test and fix radon in the state and the disclosure rule for home sales.

Phone (800) 325-1245

Visit the program's page (opens in a new tab)Read November 3, 2026

Nearby

Listed professionals in states next to Illinois

A business licensed in a neighboring state is licensed there, not necessarily in Illinois. Check Illinois's rule above before you hire one.

Before you hire

How to check a credential in Illinois

  1. Illinois's own list

    Start with the Illinois Emergency Management Agency (IEMA). Licensing is done by the state, so its list or search says who may legally work in Illinois.

  2. NRPP's search

    The National Radon Proficiency Program's search finds its Certified Mitigation Specialists and Certified Measurement Professionals by area, by name, or by the 6-digit NRPP ID number a professional can give you.

  3. NRSB's search

    The National Radon Safety Board's search finds a professional in your area, or confirms that a named professional is NRSB certified.

  4. The ID card

    The programs usually issue a photo ID card showing the holder's qualifications and its expiry date. Ask to see it, and if in doubt, check with the body that issued it.

Hiring

Hiring in Illinois

A tester

266 businesses are listed for testing here. Ask for the credential and ID card, how the test will be guarded against interference, and when the report will come. EPA recommends an independent, qualified tester for the test after a system is installed.

What a professional test involves

A mitigation contractor

89 businesses are listed for mitigation here. Get more than one estimate, contact references, and ask for a written proposal and a contract before any work starts.

How to choose a contractor

Questions

Common questions about Illinois

Does Illinois require radon professionals to be licensed?

Yes. Illinois's radon program page, checked on November 3, 2026, says.

EPA's state contacts page lists Illinois among the states with radon credentialing programs.

The Agency also licenses and regulates the individuals who provide radon measurement and mitigation to the public.
How do I find a certified radon mitigator in Illinois?

Radon411 lists 89 businesses for mitigation in Illinois, each with the source that lists it.

Your state radon program can help you find qualified professionals in the state, and NRPP and NRSB, the two national proficiency programs EPA names, each publish a search of the professionals they certify.

Mitigation listings for IllinoisHow to choose a mitigation contractor

Who tests for radon in Illinois?

Radon411 lists 266 businesses for radon measurement in Illinois.

A qualified radon tester is very often a home inspector, and your state radon office can give you its approved list of radon testing companies.

Testing listings for IllinoisWhat a professional radon test involves

Does Illinois have a radon disclosure rule for home sales?

IEMA-OHS Radon Program's page, checked on November 3, 2026, says:

Illinois Radon Awareness Act - This is the legislation that requires the seller to provide to the buyer of any interest in residential real property the IEMA-OHS pamphlet entitled "Radon Testing Guidelines for Real Estate Transactions" and the Illinois Disclosure of Information on Radon Hazards.

Every state's program, licensing and disclosure rule

How current are the Illinois listings?

Listings for Illinois come from the list of licensed radon professionals that the Illinois Emergency Management Agency (IEMA) publishes, last read on November 11, 2026, and from businesses that confirm their own details through Radon411's claim process.

Is every business on this page licensed in Illinois?

No listing here is a license. The first list holds businesses Illinois's own registry lists, or that confirmed their own listing; each card names its source.

2 businesses with an address in Illinois appear in a separate list because another state's registry lists them. That does not mean Illinois licenses them.

How listings are verified. Run a radon business in Illinois? Get Featured.

Next steps

Where to go next