- Official section
- Illinois III.K: Radon Resistant Construction Act
- Broker weight
- Part of 25% of the Illinois state portion
- Expected scored items
- Additional Illinois Laws and Regulations accounts for about 10 of 40 state items
Illinois laws and regulations topic guide
Illinois Radon Resistant Construction Act
A white pipe through a new home's attic is not proof that the home is radon free. It is infrastructure: a passive route that helps resist soil-gas entry and can accept a fan later if testing shows the need. That one idea makes the Act easier to remember. Construction prepares, measurement verifies, and licensed active mitigation corrects.
Last updated: August 1, 2026
What does current Illinois authority require?
Short answer: Since June 1, 2013, defined new residential construction throughout Illinois must include passive radon-resistant construction. The definition covers original construction of a single-family home or a dwelling containing two or fewer apartments, condominiums, or townhouses. The passive system uses natural airflow through a prepared soil-gas collection and vent path; it does not include a fan and does not guarantee a low radon level. The residential builder, subcontractors, or a radon contractor may install passive construction during the build. Only a licensed radon contractor may add the fan or upgrade the system to active mitigation. Local standards may be at least as stringent as state rules.
The PSI broker outline effective June 24, 2026 lists the Radon Resistant Construction Act in Illinois III.K. This guide uses 420 ILCS 52 and 32 Ill. Adm. Code 422.160 current through August 1, 2026. The agency named in the statute is the Illinois Emergency Management Agency, while the current state program is presented through IEMA-OHS. The construction rule is distinct from Radon Awareness Act disclosures and transaction measurement protocols. Local code officials and licensed radon professionals decide project-specific compliance.
Where is this tested on the Illinois outline?
- Topic
- Why radon matters
- What to know
- Naturally occurring uranium, radioactive decay, soil gas, colorless, odorless, tasteless, foundation opening, indoor accumulation, lung cancer, nonsmoker risk, smoking interaction, all Illinois counties, measurement, 4.0 pCi/L action guidance, no visual inspection answer, and long-term exposure
- Best exam move
- Remember that radon cannot be cleared by sight or smell; construction reduces entry potential while measurement establishes concentration.
- Topic
- Covered new residential construction
- What to know
- Original construction, Illinois, single-family home, dwelling, two or fewer apartments, two or fewer condominiums, two or fewer townhouses, effective June 1 2013, residential building contractor, new project, no existing-home assumption, no large multifamily assumption, and exact definition
- Best exam move
- Check original construction and dwelling type before applying the statewide passive-system mandate.
- Topic
- Passive radon-resistant construction
- What to know
- Passive new-construction pipe, natural convection, soil-gas depressurization path, no mechanical fan, below foundation, conditioned-space route, above roof, entry resistance, future activation, system label, and no result guarantee
- Best exam move
- Treat passive as fan-ready construction, not as an operating active system or a promise of less than 4.0 pCi/L.
- Topic
- Gas-permeable subfloor layer
- What to know
- Concrete slab, floor in contact with ground, living-space walls, soil-gas movement, clean aggregate, minimum four inches, sand, minimum four inches, geotextile drainage mat, perimeter, alternate demonstrated design, lateral flow, sub-slab communication, and future depressurization
- Best exam move
- The base layer lets soil gas move toward the collection point instead of trapping it in isolated pockets.
- Topic
- Soil-gas retarder
- What to know
- Polyethylene, minimum 6 mil, 3-mil cross-laminate alternative, equivalent flexible material, entire floor area, above permeable layer, before slab, sections lapped 12 inches, close around penetrations, seal punctures, seal tears, bridge slab cracks, and keep concrete out of voids
- Best exam move
- Do not call the membrane a complete radon system; it is one barrier component working with collection and venting.
- Topic
- Closing entry routes
- What to know
- Slab penetration, pipe, wire, bathtub, shower, water closet, polyurethane caulk, control joint, isolation joint, construction joint, wall joint, condensate drain, trap, nonperforated route, sump lid, gasket, floor drain inlet, masonry block, penetrations, air handler, duct, crawlspace opening, and air leakage
- Best exam move
- Close paths where soil gas can enter, but remember sealing alone is not the passive depressurization system.
- Topic
- Crawlspace sub-membrane system
- What to know
- Earthen floor, exterior vent, continuous polyethylene, minimum 6 mil, 12-inch overlap, sealed seam, foundation wall, interior pier, compatible adhesive, furring strip, tee, perforated pipe, membrane penetration, vertical vent, roof termination, adjacent opening distance, and passive SMD
- Best exam move
- For a crawlspace, place the collection path beneath a sealed ground membrane rather than treating open earth as acceptable.
- Topic
- Slab and basement sub-slab system
- What to know
- Basement, slab on grade, concrete floor, earth contact, minimum 3-inch Schedule 40 PVC, embedded in aggregate, tee, perforated pipe, perimeter drain tile loop, separate barrier area, individual vent, combined outlet, positive drainage, roof, and passive SSD
- Best exam move
- The pipe starts in the gas-permeable zone and rises through the building so future suction can reach the foundation area.
- Topic
- Vent routing and termination
- What to know
- Through building floors, conditioned-space route, above highest roof, at least 12 inches above penetration, two feet above window or conditioned-space opening, 10 feet from adjacent-building opening, separate foundations, combined vent, positive drainage to ground, roof flashing, no exhaust-impeding cap, and water tight
- Best exam move
- Route and discharge the passive pipe as a future mitigation path, not as plumbing, combustion exhaust, or an open attic termination.
- Topic
- Fan-ready electrical and access
- What to know
- Accessible attic, area outside and above habitable space, future fan location, roof-top electrical alternative, dedicated outlet in approved box, anticipated fan, minimum three feet attic piping, accessible conversion, system label each floor, accessible attic label, and no fan in passive system
- Best exam move
- The electrical outlet and usable pipe space prepare for later activation; they do not make the new system active.
- Topic
- Who may perform the work
- What to know
- Residential building contractor, subcontractor, radon contractor, passive construction during new build, licensed mitigation professional, active mitigation, vent fan, passive-to-active upgrade, radon measurement professional, home inspector, real estate broker, and no scope expansion
- Best exam move
- Builders may install the passive package during construction, but fan installation and system activation belong to a licensed radon contractor.
- Topic
- Testing after construction
- What to know
- Indoor-air measurement, lowest structural area, each foundation type, qualified measurement, short-term protocol, 48 hours, pCi/L, below 4.0 guidance, 4.0 or more, activation, mitigation, retest, renovations, two-year retest recommendation, passive pipe, and no construction certificate substitute
- Best exam move
- Use a valid measurement to decide whether passive construction is enough or licensed active mitigation should be considered.
- Topic
- State and local authority
- What to know
- IEMA, IEMA-OHS, primary state responsibility, coordination, oversight, implementation, rules, 32 Ill. Adm. Code 422.160, local government, ordinance, resolution, administration, enforcement, adoption by reference, at least as stringent, local permit, building official, and no weaker code
- Best exam move
- Apply the statewide floor and check the local code for equal or stronger construction and inspection requirements.
- Topic
- Construction, awareness, measurement, and mitigation
- What to know
- Radon Resistant Construction Act, Radon Awareness Act, disclosure pamphlet, known test result, buyer acknowledgment, Radon Industry Licensing Act, measurement, licensed contractor, passive system, active system, transaction negotiation, testing not automatically required, mitigation not automatically required by awareness disclosure, and separate duties
- Best exam move
- Name the legal job: new-build prevention, transaction disclosure, concentration measurement, or active reduction.
The RADON method for Illinois construction questions
- Recognize the project. Confirm original Illinois construction and a single-family home or qualifying dwelling containing two or fewer apartments, condominiums, or townhouses.
- Assemble the passive path. Look for gas-permeable material, a soil-gas retarder, closed entry routes, sub-slab or sub-membrane collection, vent piping, and roof discharge.
- Design for later activation. Confirm pipe labels, positive drainage, accessible fan location, the electrical outlet, and enough attic pipe for a future licensed fan.
- Observe the work boundary. Builders and subcontractors can install passive construction during the build; licensed radon contractors control fan installation and active mitigation.
- Note testing and local law. Passive construction never replaces an indoor-air measurement, and a local jurisdiction may impose equal or stronger construction requirements.
- Checkpoint
- Effective date
- Current rule
- June 1, 2013
- Exam warning
- Use current project and code facts
- Checkpoint
- Geography
- Current rule
- All areas of Illinois
- Exam warning
- No high-risk-county limitation
- Checkpoint
- Single-family
- Current rule
- Original construction covered
- Exam warning
- Existing remodel differs
- Checkpoint
- Small dwelling
- Current rule
- Two or fewer apartments, condos, or townhouses
- Exam warning
- Not every multifamily project
- Checkpoint
- Required system
- Current rule
- Passive radon-resistant construction
- Exam warning
- No fan required by passive definition
- Checkpoint
- Subfloor layer
- Current rule
- Minimum 4-inch listed aggregate or sand system
- Exam warning
- Alternative demonstrated designs possible
- Checkpoint
- Membrane
- Current rule
- Minimum 6 mil or 3-mil cross-laminate equivalent
- Exam warning
- Lap sections at least 12 inches
- Checkpoint
- Slab pipe
- Current rule
- Minimum 3-inch Schedule 40 PVC
- Exam warning
- Starts in permeable layer
- Checkpoint
- Roof termination
- Current rule
- At least 12 inches above highest roof penetration
- Exam warning
- Opening-distance rules also apply
- Checkpoint
- Future fan
- Current rule
- Accessible location, outlet, and at least 3 feet of attic pipe
- Exam warning
- Preparation is not activation
- Checkpoint
- Passive installer
- Current rule
- Builder, subcontractor, or radon contractor
- Exam warning
- During new residential construction
- Checkpoint
- Active installer
- Current rule
- Radon contractor only
- Exam warning
- Includes vent fan and upgrade
- Checkpoint
- Health guidance
- Current rule
- Home level below 4.0 pCi/L recommended
- Exam warning
- Only testing reveals concentration
- Checkpoint
- Local code
- Current rule
- May be at least as stringent
- Exam warning
- Check local administration
Which Illinois distinctions matter most?
- Terms
- Original construction vs. existing-home renovation
- Difference
- The Act defines new residential construction as original construction of specified homes. A remodel or ordinary addition to an existing home is not automatically that defined project.
- Question cue
- New dwelling or work on an existing one?
- Terms
- Passive system vs. active system
- Difference
- A passive system relies on natural airflow and has no vent fan. An active system uses a fan for mechanically driven soil depressurization.
- Question cue
- Natural convection or powered suction?
- Terms
- Radon-resistant vs. radon-free
- Difference
- Construction methods resist entry and prepare for mitigation. They do not establish a zero reading, a safe-level warranty, or a substitute for indoor-air testing.
- Question cue
- Risk-reduction design or measured result?
- Terms
- Soil-gas retarder vs. vent pipe
- Difference
- The membrane reduces entry and bridges cracks. The vent path collects and routes soil gas to discharge above the roof.
- Question cue
- Barrier or depressurization path?
- Terms
- Sub-slab vs. sub-membrane
- Difference
- Sub-slab collection serves concrete floors and permeable material beneath them. Sub-membrane collection serves earth floors or crawlspaces under sealed sheeting.
- Question cue
- Concrete slab or exposed soil?
- Terms
- Builder work vs. licensed radon work
- Difference
- The residential builder or subcontractors may install passive construction during the build. Only a radon contractor may add a fan or make the system active.
- Question cue
- Passive rough-in or powered mitigation?
- Terms
- Construction inspection vs. radon test
- Difference
- An inspection can confirm visible components and code details. A radon measurement determines the indoor concentration.
- Question cue
- Is it built correctly or what is the pCi/L?
- Terms
- 4.0 pCi/L guidance vs. legal construction trigger
- Difference
- The state recommends keeping homes below 4.0 and considering mitigation above it. New-construction duties apply by project definition, not by a preconstruction radon test.
- Question cue
- Health action level or mandatory build scope?
- Terms
- State minimum vs. local standard
- Difference
- The state rule establishes a statewide floor. A local government may administer and enforce equal or more stringent radon-resistant standards.
- Question cue
- Baseline or added local protection?
- Terms
- Construction Act vs. Awareness Act
- Difference
- The Construction Act requires passive features in defined new homes. The Awareness Act governs radon information and disclosure in covered residential sales.
- Question cue
- How built or what disclosed?
How does the Illinois rule apply?
A new duplex
Scenario: A builder begins original construction of a duplex in an Illinois county that the buyer believes has low radon potential. The builder argues that no passive pipe is necessary because no elevated test exists.
- A duplex is a dwelling containing two apartments.
- The project is original construction in Illinois.
- The statewide mandate is not limited to selected radon zones.
- The construction duty does not depend on a preconstruction indoor-air result.
- Passive radon-resistant construction must be included.
Answer: The new duplex is covered statewide and requires the passive construction package.
A large new apartment building
Scenario: A developer constructs a new 40-unit apartment building and asks whether the definition in 420 ILCS 52 automatically controls the project.
- The project is original residential construction.
- However, the statutory definition names a single-family home or dwelling containing two or fewer apartments, condominiums, or townhouses.
- Forty apartments exceed that stated scope.
- The Act's specific definition therefore does not automatically cover the project.
- Other state codes, local ordinances, financing rules, or voluntary standards still require review.
Answer: The 40-unit building is outside this Act's stated new-residential-construction definition, but other requirements may apply.
The pipe has no fan
Scenario: A buyer sees a labeled pipe running from beneath the slab through the attic and above the roof. There is an outlet and open pipe space in the attic but no fan.
- The below-slab-to-roof path is consistent with passive construction.
- The outlet and attic space prepare for future activation.
- The absence of a fan means it is not an active soil-depressurization system.
- Natural airflow can occur without powered suction.
- A valid radon test is still needed to know the indoor concentration.
Answer: The facts describe a passive, fan-ready radon system, not proof of active mitigation or a low reading.
The builder wants to add the fan
Scenario: After a new home tests at 6.2 pCi/L, the general contractor offers to install a vent fan personally because the passive pipe is already present. The contractor has no radon mitigation license.
- The test result raises a mitigation concern under current health guidance.
- The passive pipe makes conversion easier but does not expand the builder's legal scope.
- Section 25 reserves fan installation and passive-to-active upgrades to a radon contractor.
- The general contractor is not stated to hold that license.
- A licensed radon contractor should design and perform the activation.
Answer: The unlicensed general contractor may not perform the fan upgrade; use a licensed radon contractor.
Two separated foundation areas
Scenario: A covered home has a basement and a crawlspace separated so soil gas cannot move freely between their collection areas. The plan uses one pipe only beneath the basement slab and no crawlspace membrane path.
- The basement calls for a sub-slab collection path.
- The earth-floor crawlspace calls for a sealed sub-membrane path.
- Separated foundation areas cannot be assumed to communicate.
- The rule calls for separate vent pipes or a continuous connected drain-tile route as applicable.
- The current one-pipe basement-only plan leaves the crawlspace unserved.
Answer: Revise the design so both foundation types have a compliant connected or separate collection and vent path.
The inspection passed but no one tested
Scenario: A local official confirms the passive components in a new home satisfy the adopted construction code. The seller then advertises the home as tested radon safe, although no indoor-air measurement occurred.
- The official confirmed construction compliance, not an air concentration.
- Passive features resist entry and prepare for mitigation.
- Radon cannot be detected by the senses.
- Only a measurement produces a pCi/L result.
- The advertised claim is unsupported by the inspection alone.
Answer: Do not claim the home was tested or is radon safe. State the verified passive features and obtain a valid measurement for concentration claims.
Where do candidates misread the Illinois rule?
- Trap
- Radon-resistant construction is required only in high-radon counties.
- Correction
- The statute and rule apply to defined new residential construction in all areas of Illinois.
- Trap
- Every new apartment building is within the Act.
- Correction
- The definition is limited to a single-family home or a dwelling containing two or fewer apartments, condominiums, or townhouses.
- Trap
- A passive system always includes an operating fan.
- Correction
- Passive construction relies on natural airflow. Adding a fan converts or upgrades it to active mitigation.
- Trap
- A passive pipe proves the home is below 4.0 pCi/L.
- Correction
- Construction does not generate an indoor-air result. The home must be tested to determine its radon concentration.
- Trap
- Sealing cracks alone is the required system.
- Correction
- Sealing is one entry-control component. The compliant passive package also needs a collection layer or membrane and vent path.
- Trap
- The radon pipe may end inside the attic.
- Correction
- The vent path terminates above the highest roof under the rule's stated height and opening-distance requirements.
- Trap
- Any builder can add the fan after a high test.
- Correction
- Only a radon contractor may install the fan or upgrade passive pipe to an active mitigation system.
- Trap
- A home inspector can certify a radon concentration by viewing the system.
- Correction
- A visual inspection assesses components. A valid radon measurement is needed for concentration.
- Trap
- A local government may replace the state rule with a weaker code.
- Correction
- Local radon-resistant construction regulations must be at least as stringent as the state rules.
- Trap
- The construction Act is the seller's radon disclosure law.
- Correction
- New-build construction and transaction disclosure serve different purposes under different statutes.
Can you apply the rule to a fresh scenario?
These questions are original study items aligned to the published outline. They are not copied, recalled, or predicted PSI questions.
1. Which project is new residential construction under 420 ILCS 52?
- Original construction of an Illinois duplex
- Painting an existing office
- Renovating a 50-unit apartment building
- Replacing a roof on a warehouse
Show answer and explanation
Answer: Original construction of an Illinois duplex
A duplex is original construction of a dwelling containing two apartments, within the statutory definition.
2. What powers a passive radon-resistant system?
- Natural convective airflow
- A mandatory vent fan
- A furnace blower
- A sump pump motor
Show answer and explanation
Answer: Natural convective airflow
Passive new-construction pipe relies on natural airflow. Mechanically driven suction is active mitigation.
3. Who may install passive radon-resistant construction during a covered new build?
- The residential builder, subcontractors, or a radon contractor
- Only a real estate broker
- Only the future buyer
- Only the county recorder
Show answer and explanation
Answer: The residential builder, subcontractors, or a radon contractor
Section 25 permits those parties to install the passive construction package during new residential construction.
4. Who may add a radon vent fan to the passive pipe?
- A licensed radon contractor
- Any unlicensed electrician
- The listing broker
- Any home inspector
Show answer and explanation
Answer: A licensed radon contractor
Fan installation and conversion of passive pipe to an active system are reserved to a radon contractor.
5. What does code-compliant passive construction prove about indoor radon concentration?
- Nothing specific until the home is tested
- The result is exactly zero
- The result is always under 2.0 pCi/L
- Testing is prohibited
Show answer and explanation
Answer: Nothing specific until the home is tested
Passive features resist entry and prepare for mitigation, but only an indoor-air measurement determines the concentration.
How should you review this Illinois topic?
- Session
- 1. Define scope and purpose
- Focus
- Radon, soil gas, health risk, original construction, single-family, duplex, two or fewer apartments, condominiums, townhouses, June 1 2013, statewide, passive requirement, and no large-building assumption
- Proof you are ready
- Classify 25 projects as covered or outside the definition and explain the decisive fact.
- Session
- 2. Trace the passive path
- Focus
- Gas-permeable layer, four inches, membrane, 6 mil, 12-inch lap, sealed penetration, sump cover, sub-slab, sub-membrane, 3-inch PVC, positive drainage, roof termination, label, and foundation separation
- Proof you are ready
- Draw a slab and a crawlspace system from soil to roof and label each required function.
- Session
- 3. Separate passive and active
- Focus
- Natural convection, no fan, future fan access, electrical outlet, three feet of attic pipe, active soil depressurization, mechanical suction, builder, subcontractor, licensed radon contractor, fan installation, and conversion
- Proof you are ready
- Sort 20 installation tasks by who may perform them and whether they create a passive or active system.
- Session
- 4. Connect construction to testing
- Focus
- Visual inspection, indoor-air measurement, pCi/L, 4.0 guidance, lowest structural area, each foundation type, short-term test, mitigation, activation, retest, renovation, and no guarantee
- Proof you are ready
- Explain in 60 seconds why a compliant passive pipe does not establish a radon result.
- Session
- 5. Compare related laws
- Focus
- Construction Act, Awareness Act, Industry Licensing Act, builder scope, measurement licensee, mitigation contractor, disclosure, known result, testing negotiation, local ordinance, state floor, enforcement, and professional referral
- Proof you are ready
- Match 25 scenarios to new construction, disclosure, measurement, active mitigation, or local code review.
- Session
- 6. Apply RADON
- Focus
- Project scope, passive components, fan readiness, work boundary, measurement, local standard, IEMA-OHS, code official, licensed contractor, broker statement, and documentation
- Proof you are ready
- Score at least 90% on a fresh Illinois radon-construction set and explain every answer in RADON order.
Do not count recognition as mastery. Close the notes and explain the rule, apply it to a new fact pattern, and identify why each distractor fails.
Practice the Illinois rule in context
From concept to decision
Drill this topic, then review the explanation
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Questions students ask about Illinois Radon Resistant Construction Act
What does the Illinois Radon Resistant Construction Act require?
All new residential construction within the Act's definition must include passive radon-resistant construction. The statute defines that construction as installation of passive new-construction pipe, while the implementing rule adds the gas-permeable layer, soil-gas retarder, sealed entry routes, passive depressurization path, labels, future fan access, electrical outlet, and related design details. The requirement applies throughout Illinois, not only in counties thought to have higher radon potential.
Which homes count as new residential construction under the Illinois Act?
The statutory definition covers original construction of a single-family home or a dwelling containing two or fewer apartments, condominiums, or townhouses. It does not say every residential building of every size, and ordinary renovation of an existing home is not original construction. Always test the project against the exact definition and any local code that is at least as stringent as the state rule.
Is passive radon-resistant construction an active mitigation system?
No. A passive system relies on natural convective airflow through the vent path and has no radon vent fan. An active mitigation system uses a mechanically driven fan to depressurize soil beneath a slab, membrane, drain tile, or block wall. Passive rough-in prepares the home to resist entry and makes later activation easier, but it does not prove that the indoor radon concentration is below any particular level.
Who may install passive radon construction in Illinois?
During new residential construction, the passive radon-resistant work may be performed by the residential building contractor, the contractor's subcontractors, or a radon contractor. This is a specific statutory permission for the passive construction package. It does not authorize an ordinary builder or subcontractor to install a radon vent fan or convert the passive pipe into an active mitigation system.
Who may install an active radon mitigation system in Illinois?
Only a radon contractor may install an active mitigation system, add a radon vent fan, or upgrade passive new-construction pipe to an active system. Illinois licenses radon measurement and mitigation professionals through the state radon program. A real estate broker, home inspector, general contractor, electrician, or homeowner should not be described as authorized to perform licensed mitigation work merely because that person noticed a pipe or high result.
What are the main parts of Illinois passive radon construction?
The current rule uses a gas-permeable subfloor layer, a polyethylene soil-gas retarder, sealed entry routes and sumps, a passive sub-slab or sub-membrane vent path, properly routed and labeled piping, positive drainage, roof termination, future fan access, a nearby electrical outlet, and enough attic pipe for later fan installation. Crawlspace and slab foundations use different collection details, and separated foundation areas may need distinct pipes or a continuous connected path.
Does a passive radon system mean the home does not need testing?
No. Radon is invisible and has no smell or taste, so measurement is the only way to know the indoor concentration. Passive construction may reduce entry and prepares the building for activation, but it is not a test result. Current Illinois health guidance recommends a home level below 4.0 picocuries per liter and consideration of mitigation when the result exceeds 4.0. Testing and any licensed activation are separate steps.
Can an Illinois municipality adopt its own radon construction rule?
Yes. A local governmental unit with a radon-resistant construction ordinance, resolution, or law may administer and enforce it. A governmental unit may adopt the state rules by reference or adopt regulations at least as stringent as the rules promulgated by the state agency. The phrase at least as stringent is important: local standards can add protection but cannot be used as a weaker substitute.
Is the Radon Resistant Construction Act the same as the Illinois Radon Awareness Act?
No. The construction Act governs passive radon features in defined new residential construction. The Radon Awareness Act concerns information and disclosure in covered residential real estate transactions. Neither should be confused with actual testing, licensed measurement, active mitigation, or a contractual agreement about who will pay for work. The exam often tests the purpose of each law rather than technical construction dimensions.
Are these official Illinois real estate exam questions?
No. They are original study questions aligned to the Illinois Radon Resistant Construction Act in Illinois III.K of the PSI broker outline effective June 24, 2026. The statute, current 32 Illinois Administrative Code Part 422 construction rule, IEMA-OHS radon program, IDPH guidance, and related licensing and awareness statutes were reviewed through August 1, 2026.
Primary sources
- PSI Illinois Candidate Information Booklet dated June 24, 2026
- 420 ILCS 52, current Radon Resistant Construction Act
- 420 ILCS 52/15, new construction and passive-system definitions
- 420 ILCS 52/20, statewide passive radon construction requirement
- 420 ILCS 52/25, passive and active installer qualifications
- 420 ILCS 52/35, at-least-as-stringent local standards
- 32 Ill. Adm. Code 422.160, new residential construction standard
- IEMA-OHS, current Illinois Radon Program
- Illinois Department of Public Health, current radon guidance
- 420 ILCS 46, Illinois Radon Awareness Act
- 420 ILCS 44, Radon Industry Licensing Act
The current official outline controls the tested scope. Statutes, regulations, and official agency materials control when a general study rule and a jurisdiction-specific rule differ.
Editorial status
Checked against primary sources
The Pass Illinois editorial team last checked this guide on August 1, 2026. Every practice question is an original study item, and the source links above let you verify the rules that support the lesson.