IEMA - Guide to Radon Mitigation (Illinois Emergency Management Agency)
Your radon level is 4 picocuries per liter (pCi/L) or higher. What are your options?
Contact a mitigation professional licensed by DNS to reduce the radon levels in your home.
Request two or three price estimates from licensed mitigation professionals. The cost of a radon
reduction system generally ranges from $900 to $2500, depending on characteristics of the house
and choice of radon reduction methods.
Talk to your mitigator and be sure you understand the mitigation design.
Residents of a dwelling may install a mitigation system in their own dwelling; however without proper
equipment or technical knowledge, you could actually increase your radon level or create other
IEMA Assures Consumer Protection
Mitigation Systems Reduce Radon By:
Mitigation Systems In Illinois Must Include:
Active sub-slab suction uses a fan to draw radon from beneath the house. SSD systems collect radon
prior to entry and exhaust it to a safe location above the highest eave.
Sub-Membrane Pressurisation (SMD)
SMD is performed in crawl spaces and areas that are directly in contact with rock or soil. Suction is
Discharge above the highest eave ensures that there is significant dilution of exhaust by outdoor air
to minimize re-entry into the house and minimize exposure to persons in the yard and neighboring
areas. To ensure public health and safety, IEMA requires that the point of discharge from fan-
powered soil Pressurisation systems be located:
Sealing enhances radon reduction techniques, such as SSD, SMD and Heat Recovery Ventilation.
Reducing the loss of conditioned air increases radon reduction system effectiveness and cost
efficiency. DNS does not recommend the use of sealing alone to reduce radon concentrations.
Sealing alone has not been shown to lower radon levels significantly or consistently.
New Construction Systems:
Since 1995, radon control methods have been part of the Council of American Building Officials
(CABO) "One and Two Family Dwelling Code." Several Illinois municipalities have adopted variations
of the CABO code requiring the installation of radon control methods in newly constructed residences.
These methods are known as passive and skeletal new construction systems. Passive or skeletal new
construction systems are not acknowledged mitigation systems and may or may not reduce radon
concentrations in homes to below the USEPA’s Action Level, 4.0 picocuries per liter of air (4pCi/L).
IEMA encourages homeowners to test their home to determine the actual radon levels. With test
results of 4 pCi/L or more, passive and skeletal new construction systems should be converted to
active soil Pressurisation systems by mitigation professionals licensed by IEMA. IEMA recommends
that post-mitigation measurements be performed by measurement professionals licensed by IEMA in
order to ensure defensibility and reliability of test results.
Passive New Construction:
Passive new construction systems rely solely on the convective flow of air upward in the vent pipe for
sub-slab Pressurisation. The system consists of a vertical vent pipe routed through conditioned space
from the suction pit to 12 inches above the roof.
Skeletal New Construction:
A skeletal system is a system that is designed for the installation of a vent fan and may consist of
multiple vent pipes. This includes vertical and angled runs that are not necessarily routed through
living space that may be joined to a single termination above the roof or may terminate separately
above the roof.
Always Perform a Post-Mitigation Test!
Post-mitigation tests are important evaluators of actual system function:
Professional post-mitigation measurements must be performed to the applicable DNS measurement
protocol. The Adopted Rule, 32 Illinois Administrative Code, Part 422, prohibits mitigation
professionals from performing radon measurements at a residence where they have installed a
For additional information about radon, radon measurement and mitigation, call IEMA at:
(800) 325-1245 or visit the
IEMA website at: Illinois State Radon Information
To Schedule a Radon
|CHICAGO - ILLINOIS - NAPERVILLE
by Illinois Licensed Radon Professionals
For a list of additional
ILLINOIS LICENSED RADON
|Residential Radon Testing
|Radon Deduction Systems, Inc
|Professional Radon Systems, Inc,
|Suburban Mitigation Specialists
|Heritage Radon Mitigation
ST. CHARLES, IL
|VSI Radon Reduction Corp.
|Du Page Radon Contractors, Inc.,
|Elliot & Associates
|Radon Management Systems
|Radon Reduction Company
GLEN ELLYN, IL