Radon in Rental Properties: Landlord Obligations and Tenant Rights

Renters face a distinctive challenge with radon: they live in the property, they breathe the air, and they bear the health consequences — but they typically cannot install a mitigation system, modify the foundation, or drill through the slab without the property owner’s authorization. The tenant’s primary tool is disclosure, advocacy, and — in states with specific protections — legal recourse. Landlords who understand their obligations avoid liability; tenants who understand their rights avoid years of unknown elevated exposure.

The Landlord’s Obligation Framework

Radon obligations for landlords operate at three levels: federal, state, and the implied warranty of habitability in common law. None of these is perfectly clear or uniformly applied, which is why radon in rental properties remains a complex area of law and public health practice.

Federal Level: HUD and Federally Assisted Housing

The clearest federal radon obligations apply to housing receiving federal financial assistance. The Department of Housing and Urban Development (HUD) has established radon requirements for federally assisted multifamily housing that include:

• Testing for radon in properties located in EPA Zone 1 counties that receive certain HUD assistance (including Section 8 project-based assistance, FHA multifamily loans, and HOME program funding)
• Mitigation requirements when radon is found above the EPA action level of 4.0 pCi/L
• Disclosure to tenants of radon test results and mitigation actions
• New HUD-assisted construction in Zone 1 must incorporate RRNC features

Tenants in HUD-assisted housing have specific rights to radon information and can contact HUD’s Office of Lead Hazard Control and Healthy Homes (OLHCHH) if their property management is not complying with radon requirements. HUD’s contact for radon inquiries is available at hud.gov/program_offices/healthy_homes/healthyhomes/radon.

State Level: Specific Radon Landlord Laws

A smaller number of states have enacted specific radon disclosure or testing requirements for rental properties. These vary significantly:

• Illinois: Illinois’s comprehensive radon program includes provisions addressing radon disclosure in certain residential rental situations. Landlords may be required to disclose known radon test results to tenants.
• New Jersey: New Jersey’s radon disclosure requirements include some rental contexts, particularly in multi-family buildings. The specific applicability depends on the building type and the nature of the tenancy.
• Maine: Maine’s radon disclosure requirements extend to certain rental contexts. The Maine CDC Radon Program provides guidance on landlord obligations.
• Other states: Requirements are evolving — check your state health department’s radon program for current landlord-specific requirements.

For current state-specific landlord radon obligations, the most reliable source is your state’s radon program (typically administered by the state health or environment department). State requirements change — information from more than two years ago may be outdated.

The Implied Warranty of Habitability

In most U.S. states, the implied warranty of habitability requires landlords to maintain rental property in a condition fit for human habitation. The specific conditions that trigger this warranty vary by state, but generally include: safe structural conditions, working utilities, freedom from health hazards, and compliance with building codes and housing standards.

Whether elevated radon constitutes a habitability defect depends on state law and, in the absence of clear statute, on how courts in that state have interpreted the habitability warranty. In states without specific radon statutes, tenants have in some cases successfully argued that elevated radon — particularly at very high levels — constitutes a habitability defect. However, this is not a well-established precedent across all states, and the outcome of any specific habitability claim is unpredictable without specific legal advice.

The key factor in habitability claims is usually notice: a landlord who has been formally notified in writing of elevated radon and has refused to investigate or remediate is in a far more vulnerable legal position than one who simply never tested. This is why the written notice process described below is important for tenants.

What Tenants Can Do: A Step-by-Step Approach

Step 1: Test Your Unit

Tenants can conduct their own radon tests using standard DIY charcoal canister kits ($15–$30 from hardware stores or online certified labs). Place the device in the lowest level of your unit where you spend time — typically the main living floor — following EPA placement protocol (20 inches above floor, 12 inches from walls, away from drafts). Run the 48-hour test under as-close-to-closed-house conditions as is practical in an occupied rental.

Note: some leases restrict alterations — a canister placed on a shelf is not an alteration. A continuous electronic monitor plugged into an outlet may be arguable depending on lease terms. Check your lease language before conducting any testing.

Step 2: Document the Results

Keep the lab report from any radon test. Document the date the test was conducted, where in the unit it was placed, and any relevant conditions (floors below tested, windows open/closed, etc.). For elevated results, consider having a certified professional retest to produce results with unambiguous chain-of-custody documentation — particularly if you anticipate needing to use the results in a legal or regulatory context.

Step 3: Notify the Landlord in Writing

Send written notice to your landlord — certified mail with return receipt requested, or email with read receipt — providing the radon test results and requesting that the landlord investigate and remediate elevated radon. Include:

• The test result (pCi/L) and the date the test was conducted
• The lab report as an attachment
• A request that the landlord arrange for professional testing and — if confirmed elevated — installation of a mitigation system
• Reference to any applicable state radon statute or the implied warranty of habitability
• A reasonable response deadline (typically 30 days)

The written notice creates a record that the landlord was informed. A landlord who ignores written notice of elevated radon and takes no action is building a record of indifference to tenant health that strengthens any subsequent legal claim.

Step 4: Escalate if Necessary

If the landlord does not respond or refuses to act within the specified timeframe:

• Contact your state radon program: State programs can sometimes provide guidance to landlords on their obligations, and in states with specific requirements, may have enforcement authority.
• Contact local housing authorities: In municipalities with active housing inspection programs, housing inspectors may have the authority to cite radon as a housing code violation in some jurisdictions.
• Consult a tenant’s rights organization or attorney: A brief consultation clarifies what legal remedies are available in your state. Remedies may include rent withholding, repair-and-deduct, lease termination for habitability failure, or civil action for damages — depending heavily on state law.
• Contact HUD if applicable: For federally assisted housing, HUD has complaint mechanisms that can compel compliance with radon requirements.

Interim Protective Measures While Advocating

While pursuing landlord cooperation, tenants can take some steps to reduce exposure — though none substitute for professional mitigation:

• Increase ventilation: Opening windows when weather permits dilutes indoor radon. This is not a long-term solution but reduces concentration during the period before mitigation is arranged.
• Spend less time on the lowest floor: If elevated radon is in the basement and you have upper-floor sleeping options, reduce time at the lowest level while working toward mitigation.
• HEPA air purifier with activated carbon: Reduces the fraction of unattached radon decay products (which are more carcinogenic per unit of radon than attached decay products) without reducing the radon gas concentration itself. A modest supplemental measure, not a solution.
• Avoid smoking indoors: The multiplicative radon-tobacco interaction means that eliminating smoking indoors in a high-radon unit reduces the combined lung cancer risk substantially, even without radon mitigation.

Frequently Asked Questions

Is my landlord required to fix a radon problem?

It depends on your state. In states with specific radon landlord statutes, yes — within the scope of those statutes. In states without specific radon laws, the implied warranty of habitability may apply if radon levels are sufficiently elevated, but this requires legal action to enforce and the outcome varies by jurisdiction and fact. For HUD-assisted housing in Zone 1 counties, federal requirements apply. Contact your state radon program and a tenant’s rights organization for state-specific guidance.

Can I test my rental unit for radon without the landlord’s permission?

Placing a charcoal canister radon test device on a shelf in your own unit is not a modification or alteration — it is equivalent to using an air quality monitor. Most leases do not prohibit this. However, drilling any holes or installing equipment would require landlord permission. Review your lease before conducting any testing and consult a tenant’s rights organization if you have concerns about lease terms.

What radon level should I be concerned about in my rental?

Any result at or above EPA’s action level of 4.0 pCi/L warrants notification to your landlord and a request for professional testing and mitigation. The WHO reference level of 2.7 pCi/L is a more conservative benchmark that some tenant advocates recommend. Results between 2.0 and 4.0 pCi/L are elevated above EPA’s “consider mitigating” threshold and warrant at minimum a conversation with your landlord and consideration of whether to pursue professional testing.

Can I break my lease because of elevated radon?

Lease termination for habitability reasons is a remedy available in some states when a landlord fails to address a known habitability defect after written notice. Whether elevated radon qualifies as a habitability defect allowing lease termination depends on your state’s landlord-tenant law, the radon concentration, the landlord’s response to notification, and other factors specific to your situation. Consult a tenant’s rights attorney before terminating a lease — early termination without proper legal basis can result in financial penalties.