Illinois radon exam guide
Illinois radon disclosure: sales, rentals and tenant timelines
A seller's radon packet and a tenant's radon packet serve different transactions. Their deadlines differ too. Start with coverage, choose the right documents, then match each number to its triggering event. A disclosure requirement, a recommendation to test and a right to end a lease are separate questions.
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The short answer
For a covered sale, the seller provides the approved real-estate pamphlet, the sale disclosure form and applicable possessed elevated-radon information before the buyer is obligated. If the buyer already offered, disclosure comes before acceptance with an opportunity to review and possibly amend. Covered rentals use the tenant guide, tenant form and hazard records. The tenant provisions include a 90-day initial test window, 10-day result delivery and a 30-day lessor retest option. A separate missing-document path has a conditional 60-day election.
Reviewed October 25, 2026. PSI lists radon at Illinois IV.E.1 within the ten-question Disclosures domain; that is not this page's quota. Current compiled law identifies Public Act 103-298, effective January 1, 2024, for the expanded tenant rules. Sections 26 and 30 apply to leases entered into on or after that date, subject to coverage and exclusions. This lesson explains the public rules; it does not calculate a private termination notice, interpret a particular measurement or certify a building's safety.
Choose the transaction before the timeline
- Check coverage first. For sales, the Act defines residential real property as an interest in a manufactured housing lot or a parcel improved with one to four residential dwelling units. The tenant provisions use the separate dwelling-unit and lease definitions, including oral leases. Do not automatically carry the sale definition's unit-count limit into every rental question.
- Apply Section 20 precisely. Its listed exclusions include specified court, foreclosure, fiduciary, co-owner, succession, spouse or lineal-family, relocation and government transfers. The relocation exclusion has its own disclosure-copy condition. A unit on the third story or higher above ground level is also excluded. Section 20 expressly includes purchases and leases in its transfer definition; this is not just a sale exception.
- For a covered sale, deliver the sale materials before obligation. Provide the approved pamphlet and statutory form, with the applicable possessed information and records about elevated results. If an offer arrived first, complete disclosure before accepting it and allow review and possible amendment. No existing test does not cancel the packet requirement. Section 10 itself does not require testing or mitigation.
- For a covered rental, use the tenant package. Section 26(a) addresses application, before entering the lease, and requests during the leasing period. It identifies the Radon Guide for Tenants or approved equivalent, qualifying hazard records and the tenant disclosure form. The initial testing window starts with commencement of the agreed leasing period, not the application date.
- Follow the applicable tenant path. In the initial path, testing is optional within 90 days, with result copies to the lessor within 10 days after receipt. The lessor can use a contractor retest within 30 days after notice to disprove a hazard. Section 26(b) links its termination right to a result above the action level and the lessor electing not to mitigate. Later testing does not automatically carry the same right, and other legal rights remain distinct.
- Keep the missing-document remedy separate. If the lessor fails to supply the required documents, Section 26(e) permits testing at any point in the term. Follow its result-delivery, dispute and lessor-response conditions before using its 60-day mitigation-or-termination election. It is not a universal 60 days from moving in, receiving every test or first contacting the landlord.
- Mitigation needs the right consent and contractor. A lessor choosing mitigation uses a licensed radon contractor. A tenant also needs the lessor's express consent before starting. Section 30(b) permits the consented installation cost to be deducted in equal parts over the remaining leasing period. Do not replace that with an immediate deduction of any amount the tenant chooses.
- Keep the broker's role accurate. Explain and document the required process, convey records honestly and address actually known facts under applicable duties. A real estate license alone is not a radon-contractor credential. Do not guarantee a safe concentration, a future test result or an automatic private lease remedy.
| Rule | Trigger or scope | Important condition |
|---|---|---|
| Sale packet | Before buyer contract obligation | Post-offer delivery before acceptance, with review/amendment opportunity |
| Tenant packet | Application, before lease, or upon request during the period | Tenant guide, tenant form and qualifying hazard records |
| Initial tenant test | 90 days from agreed leasing-period commencement | Optional test; not 90 days from application |
| Result delivery | Within 10 days after tenant receives results | Provide copies, including relevant records/reports |
| Lessor contractor retest | Within 30 days after tenant notice | Measurement may disprove a hazard; no automatic pass |
| Subsection (c) result validity | Two years from testing | Renovations, additions or modifications can end it earlier |
| Subsection (e) result validity | Two years from testing | Renovation, addition or substantial modifications can end it earlier |
| Missing-document election | 60 days under the stated response conditions | Consented contractor mitigation at tenant expense, or termination |
| Third story or higher | Unit above ground level | Section 20 includes purchases and leases |
| Tenant form action level | 4.0 pCi/L | Do not turn a response level into a safety guarantee |
The distinctions that matter
| Distinction | How it works | What to notice |
|---|---|---|
| Sale package and tenant package | The sale uses its real-estate testing pamphlet and Section 10 form. The rental uses the tenant guide and Section 26 form. | Read the document heading instead of relying on a similar filename. |
| No knowledge and no records | These concern different facts. The sale form separately addresses knowledge or prior mitigation and possession of elevated-radon records. | Prior remediation is not permission to invent a never-tested history. |
| Disclosure and a testing mandate | Sections 10 and 26 do not themselves impose universal testing or mitigation. Recommendations and a particular contract can be different. | A required warning packet is not a required seller test. |
| Action level and guaranteed safety | The tenant form uses 4.0 pCi/L. EPA recommends fixing at that level or above and recognizes risk below it. | Below the action level does not mean a broker can certify zero risk. |
| Hazard definition and initial termination wording | The definition and tenant form use at or above the action level. Section 26(b) uses in excess for its initial-period termination condition. | Apply the particular provision rather than treating at and above as interchangeable. |
| Initial testing and the missing-document path | The 90-day path and the later remedy for missing required documents have different conditions. | A later test alone is not the same as a proven disclosure failure. |
| Test-result validity under subsections (c) and (e) | Both use two years from testing. Subsection (c) addresses renovations, additions or modifications; subsection (e) says renovation, addition or substantial modifications. | Preserve the particular wording and do not promise every old result lasts two full years. |
| A legal exclusion and a health conclusion | The third-story exclusion applies to the Act's transfer requirements. Radon can occur on upper floors. | An excluded transfer is not a radon-free certificate. |
| Seller report and radon packet | The general Residential Real Property Disclosure Report includes a radon-awareness item. It does not substitute for the separate radon pamphlet and form. | One signed report is not automatically every required disclosure. |
| Radon disclosure and radon-resistant construction | The Awareness Act concerns information and tenant rights. Construction requirements arise under a separate Act. | Do not import every new-construction requirement into every resale or lease. |
Work through the facts
The offer arrived first
A buyer offers on a covered two-unit residential property. No radon packet has been provided.
- The seller must complete the Section 10 disclosure steps before acceptance.
- The buyer needs an opportunity to review and possibly amend the offer.
Answer: Do not accept first and promise to deliver at closing.
No test, no invented result
A covered seller has never tested and possesses no elevated-radon records.
- The required pamphlet and form still apply.
- Complete the knowledge and records statements truthfully; do not manufacture a negative measurement.
Answer: No test is not the same as no disclosure duty, and Section 10 itself does not require a seller test.
A third-story rental
A unit is on the third story above ground level. A 2026 lease transfers possession to a tenant.
- Section 20 includes leases in its transfer definition.
- The stated third-story exclusion is a legal coverage rule, not evidence that the air contains no radon.
Answer: Apply the Act's exclusion on those facts, while identifying any separate contractual or legal duties.
A ground-floor unit in a larger building
A prospective tenant applies for a ground-floor unit in a twelve-unit building, with no Section 20 exclusion applicable.
- The rental provisions address dwelling units.
- The sale definition's one-to-four-unit cap does not itself eliminate this tenant package.
Answer: Use the covered tenant disclosure process rather than importing the sale cap.
A late report of an early test
A covered tenant tests on day 45, receives the result and sends it to the lessor 18 days later.
- The test was within the initial 90 days.
- Result delivery was due within 10 days after receipt, so the stated delivery was eight days late.
Answer: The initial test date does not excuse missing the separate reporting step; do not assume a private remedy without the full facts.
The contractor actually tests within the window
After notice of a tenant result, the lessor hires a licensed contractor and the additional test is performed 12 days after notice.
- Twelve days is within 30 days.
- The contractor's measurement may disprove a hazard; hiring alone without a timely test would be different facts.
Answer: This fits the stated retest timing, not a guaranteed scientific result.
A later test with disclosure already provided
The required tenant documents were supplied. A tenant tests on day 130 and wants the initial Section 26(b) termination right solely because a hazard is reported.
- Testing after 90 days is permitted.
- That fact alone does not create the same initial-window termination right. Other applicable law remains distinct.
Answer: Do not treat every later test as the missing-document remedy or as a waiver of every other right.
Equal rent deductions after consent
A tenant has the lessor's express consent, uses a licensed contractor and incurs $1,200 installation cost. Eight equal rental periods remain; no other facts alter the example.
- $1,200 / 8 = $150 per period.
- The statutory method spreads the deduction across the remainder, rather than subtracting $1,200 at once.
Answer: The illustrative equal deduction is $150 for each of the eight remaining periods.
A deposit after a qualifying move-out
A tenant vacates under Section 26(e). The lessor wants to charge the security deposit for radon testing and mitigation.
- Section 30(c) prohibits that compensation charge in the described covered move-out.
- Its specified exception requires both installation without lessor consent and the system not being properly installed by a radon contractor. An itemized statement is required for any part withheld.
Answer: Do not replace the statutory conditions with a blanket right to charge every radon cost to the deposit.
The result is not two years old yet
A contractor result in the subsection (c) path is 18 months old when the building is modified.
- Subsection (c) makes building changes relevant to validity before two years expire.
- Do not treat the two-year number as unconditional or apply the different subsection (e) wording without checking the path.
Answer: The age of the report alone does not establish its continued statutory validity.
Mistakes to avoid
- The third-story exclusion applies only to sales. Section 20 expressly includes purchases and leases.
- A twelve-unit building cannot have covered tenant disclosures. Use the dwelling-unit rental provisions rather than automatically importing the sale cap.
- A tenant may test for only 90 days. Later testing is allowed; the statutory remedies and conditions differ.
- Exactly 4.0 settles every termination question. Distinguish the hazard definition and form from subsection (b)'s in-excess wording and other conditions.
- Hiring a contractor on day 29 always proves timely testing. The statutory option concerns performance of the additional test within the window.
- Every tenant can deduct mitigation costs without consent. Express lessor consent and a licensed contractor are required.
- A current official page link always opens the intended form. Check whether the document is for sales or tenants and use the statutory form for the transaction.
- A broker signature guarantees the property is safe. Acknowledge the actual process and information without inventing a technical certification.
Check your understanding
These are original teaching questions, not recalled or predicted PSI questions. Answer first, then explain why the other choices fail.
1. For a covered Illinois sale, when must the Section 10 radon packet be provided?
- Before the buyer is obligated under a purchase contract
- Only at closing
- Within 90 days after the deed
- Only after a positive test
Show answer and explanation
Answer: A. Before the buyer is obligated under a purchase contract
Section 10 requires the approved pamphlet and form before buyer obligation. No existing test is not an exemption from that package.
2. A buyer offered before receiving the radon disclosures. What is the correct next step?
- Accept immediately and disclose later
- Wait until the deed is recorded
- Complete disclosure before acceptance and allow review and possible amendment
- Require an oral waiver
Show answer and explanation
Answer: C. Complete disclosure before acceptance and allow review and possible amendment
Section 10(c) expressly addresses the offer-first sequence. An offer already being submitted does not eliminate the review opportunity.
3. What does Section 20 say about the term transfers for its exclusions?
- It excludes every lease from the definition
- It applies only to recorded deeds
- It includes legal transfers of possession, including purchases and leases
- It depends only on whether the rent is paid in cash
Show answer and explanation
Answer: C. It includes legal transfers of possession, including purchases and leases
The section expressly includes leases. Apply the specified exclusion facts rather than assuming the third-story rule is confined to sales.
4. A ground-floor dwelling unit is in a twelve-unit building, and no Section 20 exclusion applies. What is correct?
- The sale unit-count definition does not itself eliminate the tenant package
- All rentals are excluded above four units
- Only the seller pamphlet applies
- A tenant must buy the unit first
Show answer and explanation
Answer: A. The sale unit-count definition does not itself eliminate the tenant package
Section 26 uses the separate dwelling-unit and lease definitions. Do not import the residential-sale cap as a blanket rental exemption.
5. What starts the tenant's initial 90-day test window?
- Commencement of the agreed leasing period
- The seller's closing
- Receiving a mortgage statement
- Submitting the application
Show answer and explanation
Answer: A. Commencement of the agreed leasing period
The initial window starts at the agreed leasing-period commencement. The result-delivery and lessor-retest clocks have different triggers.
6. A covered tenant receives radon results. When does Section 26 require copies to the lessor?
- Only after a second annual test
- Never if the result was privately obtained
- Within 10 days after receiving the results
- Within 30 days after lease signing
Show answer and explanation
Answer: C. Within 10 days after receiving the results
The tenant's result receipt starts the 10-day reporting period. It is separate from the 90-day initial testing window.
7. A lessor disputes a qualifying tenant result. What fits the statutory retest option?
- Use a radon contractor to perform the additional test within 30 days after notice
- Erase the original report
- Hire someone on day 29 regardless of when testing occurs
- Have an unlicensed broker announce a safe result
Show answer and explanation
Answer: A. Use a radon contractor to perform the additional test within 30 days after notice
The provision concerns an additional test performed within the window, not hiring alone. The contractor measurement may disprove a hazard; a lower result is not guaranteed.
8. Which statement best describes an initial-window test of exactly 4.0 pCi/L?
- The hazard definition/form use at or above, while subsection (b) uses in excess for its termination condition
- It guarantees safety
- It automatically proves every lease-termination condition
- It means the tenant may never test again
Show answer and explanation
Answer: A. The hazard definition/form use at or above, while subsection (b) uses in excess for its termination condition
Preserve the wording of the particular provision. The result alone does not settle the lessor-response condition, retest option or every other available right.
9. Required documents were supplied, and a tenant tests on day 130. What follows from that fact alone?
- The lessor necessarily failed to disclose
- Later testing is permitted, but the same initial-window termination right is not automatically established
- The test is forbidden
- The tenant waived every legal right
Show answer and explanation
Answer: B. Later testing is permitted, but the same initial-window termination right is not automatically established
Section 26(b) permits later testing while distinguishing its termination route and preserving rights under other applicable law. A missing-document remedy requires the missing-document facts.
10. What is required before a tenant undertakes radon mitigation under Section 30(b)?
- A guarantee that the work costs less than the deposit
- An oral statement from any neighbor
- Only a real estate broker's license
- Express lessor consent and a radon contractor
Show answer and explanation
Answer: D. Express lessor consent and a radon contractor
The tenant needs express consent before starting and installation by a licensed radon contractor. A claimed hazard does not create unrestricted permission to alter the property.
11. Consented contractor installation costs $1,200, with eight equal rental periods remaining. Under the stated equal-part deduction example, what is the amount per period?
- $150
- $1,200
- $800
- $100
Show answer and explanation
Answer: A. $150
$1,200 / 8 = $150. The example applies the equal-part rule across the remaining period, not an immediate full-cost rent deduction.
12. A tenant has the required documents and acknowledges a test result below the action level. What may a broker safely conclude from those facts?
- Every future test will be lower
- Those facts do not establish a guarantee of zero risk or future results
- The disclosure signature is a technical safety certificate
- No radon can ever enter the building
Show answer and explanation
Answer: B. Those facts do not establish a guarantee of zero risk or future results
A disclosure acknowledgment records information and receipt. EPA explains that the action level is not a no-risk boundary, and a real estate license alone does not authorize technical certification.
Common questions
What must an Illinois seller disclose about radon?
For a covered sale, provide the approved real-estate pamphlet, the Section 10 sale form and the applicable possessed information and records about elevated results. The form distinguishes knowledge, prior mitigation and records. No test does not justify inventing a negative result or omitting the required packet.
Can the seller wait until closing?
No. The sale packet is due before buyer obligation. If the buyer already made an offer, complete disclosure before accepting it and allow review and possible amendment. Keep that timing separate from general seller-report, inspection and closing duties.
Does Illinois require every seller to test or mitigate?
Section 10 itself does not impose that universal requirement. IEMA-OHS recommends testing, and a particular agreement or other applicable law can add duties. Disclosure, a recommendation and a contractual testing promise are different concepts.
Does the third-story exclusion include rentals?
Yes. Section 20 expressly includes purchases and leases in its transfer definition and excludes units on the third story or higher above ground level. That legal exclusion is not a finding of zero exposure; IEMA-OHS notes that radon can be found on upper floors.
Are all transfers by relatives, trusts or relocation companies excluded?
Do not use those labels alone. Section 20 identifies particular relationships and transactions. Its relocation-entity exclusion requires the seller's disclosure form to be made available to prospective buyers. A trust, relative or relocation label is not a substitute for matching the statutory conditions.
What is in the tenant radon package?
The Radon Guide for Tenants or approved equivalent, qualifying records or reports indicating a hazard in the unit, and the Section 26 tenant disclosure form. Section 26(a) addresses application, before lease entry, and requests during the leasing period. Use the tenant materials for a covered rental.
Can an oral lease be covered?
Yes. The Act's lease definition includes oral and written agreements for the stated rent and period. Coverage and Section 20 exclusions still matter. The absence of a signed lease is not by itself a universal radon-disclosure exemption.
How do the 90, 10 and 30 days fit together?
Ninety days runs from commencement for the initial tenant test. Ten days runs from the tenant receiving the results for providing copies. Thirty days runs from tenant notice for the lessor's contractor retest option. They are not three consecutive waiting periods that can always be added into one deadline.
What does exactly 4.0 pCi/L mean?
The tenant form identifies 4.0 pCi/L as the recommended action level, and the hazard definition uses at or above. Section 26(b) uses in excess for its initial-period termination condition. Read that wording and the lessor-response conditions rather than inferring every remedy from one number.
Can a tenant test after the first 90 days?
Yes. The statute permits later testing and preserves other applicable rights. A later test alone does not recreate the initial Section 26(b) termination route. If required documents were not provided, the separate subsection (e) remedy must be analyzed on its own facts.
What if the lessor did not provide the documents?
Section 26(e) permits testing during the term when its disclosure-failure condition applies. It then addresses result delivery, a lessor-paid contractor retest if disputed, and the stated response conditions for a 60-day mitigation-or-termination election. Do not promise a universal move-out date without those facts and steps.
Are radon results always valid for two years?
No. The statute measures two years from testing and identifies earlier-ending building changes. Subsection (c) says renovations, additions or modifications; subsection (e) uses renovation, addition or substantial modifications. Do not erase that difference or apply a generic two-year promise to every sale or scientific measurement.
Can the tenant deduct mitigation from rent?
Section 30(b) requires a radon contractor and the lessor's express consent before tenant mitigation. With that consent, installation cost may be deducted in equal parts across the remainder of the leasing period. It is not general permission to install first or stop paying all rent.
Can the lessor charge the deposit for radon work?
For the described Section 26(e) move-out, Section 30(c) prohibits withholding as compensation for radon testing or mitigation. Its specified exception requires installation without consent and the system not being properly installed by a radon contractor. An itemized statement is required for any part withheld. Other deposit issues need their own applicable facts and law.
Is the general seller disclosure report enough?
No. Its radon-awareness item does not replace the Awareness Act's separate pamphlet and form. Likewise, the Radon Resistant Construction Act is a separate source for qualifying construction requirements. A disclosure form is not proof that construction or mitigation requirements were completed.
Where should I get the correct Illinois radon form?
Use Section 10's statutory form for sales and Section 26's tenant form for rentals, together with the corresponding IEMA-OHS materials linked below. Check the heading before using a downloaded file: the seller and buyer lines differ from the lessor and tenant lines. A similar document name does not establish that it is the correct form for the transaction.
Does a radon disclosure signature certify safety?
No. It concerns the information, acknowledgments and certification actually stated in the document. EPA's action-level guidance recognizes risk below 4 pCi/L. A broker should not convert a receipt acknowledgment or lack of known results into a technical assurance that the dwelling is safe.
How do I study this for the Illinois exam?
Sort the facts into coverage, sale or lease, required documents, trigger and response. Then explain which condition a distractor omits. These are original practice scenarios, not PSI questions, and a practice score alone is not a validated readiness measure.
Keep practising
Your next practice step
Put environmental disclosure into practice
Distinguish the property, person and condition covered by each disclosure rule.
These web resources are free. The app has a separate free starter tier and optional paid full access.
Official sources and scope
Checked October 25, 2026. The sources identify the current statutory sale and tenant forms, their different coverage and remedies, and the corresponding IEMA-OHS materials. Check a downloaded form's transaction heading. EPA's action-level page was updated October 13, 2026. Proposed technical bills are not treated as enacted changes. This lesson does not replace the statute with an agency summary or decide a particular tenant's notice date.
- PSI June 24, 2026 outline: Illinois radon disclosure
- 420 ILCS 46/5: sale, dwelling unit and hazard definitions
- 420 ILCS 46/10: statutory sale form and disclosure timing
- 420 ILCS 46/20: exclusions include purchases and leases
- 420 ILCS 46/26: tenant forms, testing and remedies
- 420 ILCS 46/30: consent, rent deductions and deposit limits
- IEMA-OHS: approved real-estate pamphlet formats
- IEMA-OHS: tenant disclosure package and testing overview
- IEMA-OHS Radon Guide for Tenants: testing and upper floors
- EPA: action level is not a no-risk boundary
- 765 ILCS 77/35: general seller disclosure report
- 225 ILCS 454/15-25: customer protections
This is exam preparation, not advice for a specific transaction. State law and the applicable facts control. Our editorial and corrections process explains how to report an issue.