Radon Knowledge Base

Radon Questions for Renters and Student Housing

Rental homes, apartments, and student housing can raise radon questions that feel different from owner-occupied homes. This page organizes questions about lower-level bedrooms, shared buildings, test results, landlord conversations, and what a renter can reasonably ask before making assumptions. The information is homeowner and renter education, not legal advice, and building-specific decisions should involve the landlord, property manager, school housing office, or other appropriate contact. American Radon Systems focuses on mitigation work in homes and small properties, so the guidance explains when a result may call for a property review and how mitigation details such as crawlspaces, slabs, sumps, and pipe routes can affect next steps.

I rent a basement apartment. What should I know about radon?

Basement apartments tend to have the highest radon levels in any building because radon enters from the soil below and concentrates in the lowest spaces. If you haven't tested yet, that's the first thing to do - short-term test kits are inexpensive and widely available, or you can pick up a continuous monitor. The EPA recommends fixing at 4.0 pCi/L or higher, and the risk doesn't go away just because you're renting rather than owning.

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Can I test for radon in my rental?

Yes, you can absolutely test your own rental. Short-term charcoal canister tests run under twenty dollars at most hardware stores - you place one for 48-96 hours and mail it in. A continuous monitor like an Airthings or RadonEye gives you ongoing numbers. Nothing about renting stops you from knowing what the air in your home looks like.

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Should I buy a radon monitor as a renter?

It's a smart move, especially if you're on a lower floor or in a basement unit. A monitor lets you see actual long-term averages rather than a single snapshot, and if you move, you can take it with you. The entry-level Airthings Wave Plus or a RadonEye RD200 are popular options that give you a running average over time - which is what really matters for assessing your exposure.

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I bought an Airthings for my rental and it shows 5.2 pCi/L. What can I do?

That reading is above the EPA's 4.0 pCi/L action level, so it's worth taking seriously. Start by documenting it - screenshot the app, note the date and your floor level. Then bring it to your landlord in writing. A mitigation system in a rental is the landlord's responsibility to install, not yours, but you need to get them engaged. If they ignore you, look into your state's tenant protection laws or contact your local health department.

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My rental has a radon mitigation system already. How do I know it's working?

Look for the U-tube manometer on the pipe - it's a small gauge that shows whether the fan is creating suction. The fluid should be uneven on the two sides, indicating negative pressure. You can also run a radon test or use a continuous monitor to verify the actual air levels are below 4.0 pCi/L. A system that's running doesn't automatically mean it's working well; a test gives you the real answer.

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My landlord mitigated radon before I moved in but never gave me a post-mitigation report. Should I ask for it?

Yes, ask for it. A post-mitigation test result is the only way to confirm the system worked. "We installed a system" and "radon is now under control" are two different things, and you deserve to see the actual numbers. If the landlord doesn't have one, that's a sign post-mitigation testing wasn't done properly - and you should run your own test now.

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I'm renting and the landlord says the radon was fixed 5 years ago. Should I test anyway?

Yes. Radon levels can change over time as soil conditions shift, the building settles, or the mitigation fan degrades. A five-year-old result tells you what was happening five years ago. An inexpensive short-term test or a continuous monitor tells you what's happening right now, which is what actually matters for your exposure.

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I rent from a private landlord (not a company). Can I ask them to test for radon?

Absolutely. Private landlords have the same general duty to maintain a habitable home as corporate property managers. The conversation tends to be more informal with an individual landlord - sometimes that's actually easier. You could offer to do the test yourself and share the results, which takes the burden off them and gets you the information you need. Most reasonable landlords, once they understand what radon is, are willing to address it.

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I'm moving into a basement unit. What radon questions should I ask the landlord before signing?

Ask whether the building has ever been tested for radon, and if so, request a copy of the results. Ask whether a mitigation system is installed, and if it is, when it was last serviced and whether there's a post-mitigation test result. Ask if the building is in a radon zone area. And honestly, if the landlord can't answer any of these and the unit is below grade, plan to test immediately after moving in.

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I asked my landlord about radon and they acted like I was speaking a foreign language. What do I do?

That's pretty common, especially with smaller private landlords. You can educate them briefly - explain that radon is an odorless gas that comes up from the soil and can build up in lower floors, and that the EPA recommends fixing it above 4.0 pCi/L. Offer to do a simple test yourself. If you get the results and they're elevated, that gives you something concrete to work with rather than an abstract conversation about a gas they've never thought about.

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I'm renting month-to-month and the radon is high. My landlord is dragging their feet. What are my options?

Document everything in writing - your test results, the dates you notified the landlord, their responses. Check your state's radon laws and habitability codes. Some states allow tenants to withhold rent or make repairs and deduct the cost when landlords fail to address habitability issues, though the rules are strict. Your local health department may also be able to apply pressure. If none of that works and the reading is significantly elevated, you have to weigh the health risk against your practical housing options.

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My landlord offered to buy a cheap plug-in radon detector at the dollar store to "prove" the radon is fine. Should I trust that?

No. Inexpensive novelty detectors sold at dollar stores or as smoke detector add-ons are generally not validated radon measurement devices. Accurate radon testing requires either an EPA-registered lab test kit or a continuous monitor that's been calibrated and validated. Ask for a proper charcoal canister test from a state licensed lab or a name-brand continuous monitor - not a gadget that isn't designed to measure radon.

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What counts as a "high" radon level in a rental apartment?

The EPA recommends action at 4.0 pCi/L or higher. Levels between 2.0 and 4.0 pCi/L are lower-risk but worth paying attention to - the EPA says considering mitigation in that range is reasonable. Below 2.0 pCi/L is closer to average outdoor background levels. There's no level that carries zero risk, but 4.0 is the widely-used threshold for taking action.

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I'm a first-time renter and I've never heard of radon. Is it actually a big deal?

Radon is the second leading cause of lung cancer in the United States after smoking - it causes tens of thousands of deaths per year. That sounds alarming, but the risk is from long-term cumulative exposure, not from a day or a week. The good news is it's very fixable when it's found. Knowing your levels and addressing them if they're high is a simple, practical thing that matters for long-term health.

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My neighbor in the same building says their radon is fine but mine is 5.0. How is that possible?

Radon levels can vary significantly unit to unit in the same building depending on floor level, proximity to soil, the presence of cracks or penetrations, and air pressure differences between units. A ground-floor or basement unit can have levels multiple times higher than a second-floor unit. Your neighbor's result doesn't tell you anything meaningful about your unit.

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I just started renting and I want to test for radon. Where do I even get a test kit?

Short-term charcoal canister kits are available at most hardware stores - Home Depot, Lowe's, Menards - usually in the electrical or home safety section. You can also order them online or through your state radon program, which sometimes offers discounted or free kits. Place the test in the lowest livable space, leave it for 48-96 hours, then mail it to the lab in the included envelope.

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I'm renting a ground-floor apartment, not technically a basement. Do I still need to worry about radon?

Yes. Ground-floor units are in direct contact with or very close to the soil, and radon enters through concrete slabs, floor joints, and foundation penetrations. Ground-floor apartments can have radon levels just as high as basement units. Test regardless of whether you call it a basement or a ground-floor unit.

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My landlord told me radon only affects homeowners, not renters. Is that true?

No. Radon doesn't care who owns the building - it accumulates in whatever space is there. Renters in basement and ground-floor units are exposed just as much as homeowners living in the same type of space. The landlord's statement is incorrect.

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I told my landlord about high radon and they said they'll "look into it." That was two months ago. What do I do?

Put something in writing - email or text - so there's a documented record. Give a specific timeframe: "I'd like to understand the plan within two weeks." If they continue to ignore it, contact your local health department or your state radon office; some states have complaint processes. You can also consult a tenant's rights organization about your options under local habitability law.

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Does radon affect short-term health? I've been feeling tired and getting headaches. Is it radon?

Radon does not cause short-term symptoms. It's not like carbon monoxide - there's no acute poisoning effect. The danger from radon is cumulative, long-term lung-cancer risk from years of exposure to radiation. If you're having headaches, fatigue, or other symptoms, look into other causes. For any health concerns, talk to your doctor.

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My rental has a basement but I live on the second floor. Do I need to worry about radon?

The risk is lower the higher up you live in a building, but it's not zero. If radon is entering the basement and the building has poor air circulation or is tightly sealed, it can migrate upward. A test on your floor is the only way to know for sure. Most second-floor units in residential buildings have relatively low levels, but in some buildings it can still be measurable.

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What kind of radon test should I use in my rental apartment?

For a baseline check, a short-term charcoal canister test (48-96 hours) is easy and inexpensive. If you want ongoing awareness, a continuous electronic monitor like an Airthings or RadonEye gives you a running long-term average that's more meaningful than a single snapshot. Long-term alpha track tests (90 days or more) give you the most accurate seasonal average but take time.

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Can I do a radon test in my rental without telling the landlord?

Yes. There's nothing preventing you from testing the air in a space you're renting. You're breathing that air; you have every right to know what's in it. Whether you choose to share the results with the landlord is up to you - though if levels are elevated, you'll need to involve them since you can't install a mitigation system yourself.

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I want to do a short-term radon test in my apartment. Where do I place it?

Place the test in the lowest livable level you spend time in - typically the bedroom or main living area, not a utility room or bathroom. Keep it at least 20 inches off the floor, away from drafts, exterior walls, and windows. Don't test in a closet, a space that's rarely used, or right next to an HVAC vent.

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How long does a charcoal canister radon test take?

Most short-term charcoal canister tests require 48-96 hours of exposure, then you mail the canister to the lab. Results typically come back within a week of the lab receiving it, sometimes faster. The whole process is usually two to three weeks from purchase to result.

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My short-term radon test came back at 4.8 pCi/L. Is that accurate enough to act on?

Short-term tests are reliable enough to flag a potential problem, but a single short-term result has more variability than a long-term average. At 4.8, you're above the EPA action level. I'd either run a second short-term test to confirm or get a continuous monitor running. The EPA guidance is to take action if two short-term tests both come back at or above 4.0. Even so, 4.8 is not a borderline result - it's worth pursuing.

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I did two short-term tests and got 3.8 and 4.2 pCi/L. Average is 4.0. Do I need mitigation?

The EPA action level is 4.0 pCi/L. An average right at that line is a signal to take it seriously. Mitigation at 4.0 is recommended; between 2.0 and 4.0 it's worth considering. You're right at the line, and given the risk is cumulative over years, I'd lean toward addressing it rather than watching and waiting.

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Can I use a radon test I find on Amazon?

Yes, if it's a legitimate product from a reputable brand and uses an EPA-registered lab for analysis. Look for kits that include a prepaid return mailer to a state licensed lab, or continuous monitors from established brands. Avoid generic "radon alarm" devices that don't have documented measurement methodology or calibration data.

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My Airthings has been running for 3 weeks and shows 3.1 pCi/L. Is that a reliable reading?

Getting more reliable. The Airthings algorithm tends to become more accurate over the first few weeks as it builds a longer dataset. Three weeks is solid - you're starting to see a meaningful long-term average. Continue monitoring; at 3.1 you're below the EPA action level but in the range where the EPA says mitigation is worth considering. Worth watching over another month or two.

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My RadonEye is showing 6.8 pCi/L in my basement apartment. Is that device accurate?

The RadonEye RD200 is one of the better residential monitors on the market and generally performs well compared to professional test results. At 6.8 pCi/L, even with some measurement variability, you're well above the 4.0 action level. This is worth acting on - take it to your landlord with the result and date documented.

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Should I test radon in winter or summer?

You can test any time of year, and with a continuous monitor you'll see the seasonal pattern. Radon levels tend to be higher in winter because windows are closed, homes are sealed up, and heating systems can pull more air from the ground. If you test only in summer with windows open, you may get a lower reading than what you're actually exposed to on average. Many experts recommend testing during the heating season to see a realistic elevated scenario.

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I ran a radon test in my apartment while the windows were open. Do I need to redo it?

Yes. Testing with windows and doors open underestimates typical exposure because you're artificially ventilating the space. The EPA protocol for short-term testing calls for closed-house conditions (windows and exterior doors closed except for normal entry and exit) for at least 12 hours before and during the test. Redo it with closed-house conditions for an accurate result.

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My building's property manager offered to test the common areas for radon. Does that help me?

Not really, no. Common area levels don't tell you what's happening inside your unit. Radon varies unit by unit based on floor level, construction details, and pressure dynamics. A test in the lobby or hallway is basically irrelevant to what you're breathing in your apartment. If you want to know your exposure, test inside your unit.

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Do I need a professional to test radon in my rental, or can I do it myself?

You can do it yourself with a consumer test kit or monitor - no professional required. However, if you're using the results for a legal dispute with a landlord or a regulatory complaint, a test performed by a state licensed radon measurement professional carries more official weight. For your own knowledge and for approaching your landlord, a consumer test is perfectly fine.

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I've been renting for two years and never tested for radon. Is it too late to be useful?

It's never too late to test. You can't undo past exposure, but knowing the current level tells you what's happening right now - which matters for how much longer you plan to stay and whether you should push your landlord for mitigation. Test now and let the result guide your next steps.

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My landlord's property management company tested all units. My unit tested at 2.8 pCi/L. What does that mean for me?

2.8 pCi/L is below the EPA's 4.0 action level but above the typical outdoor background of around 0.4 pCi/L. The EPA says levels between 2.0 and 4.0 are worth considering mitigation - the risk is lower, but real. If you're on a lower floor and plan to stay long term, it's a reasonable thing to bring up with your landlord or monitor over time.

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My apartment radon test came back at 1.4 pCi/L. Can I stop worrying?

1.4 pCi/L is a low reading. While there's no radon level that carries zero risk, 1.4 is close to normal background levels - it's not something that warrants urgent action. Continue to be aware of it if your floor level or building use patterns change.

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Is there a free or cheap radon test program for renters?

Many states offer subsidized or free radon test kits through their state radon programs, often through the state health department or environmental agency. Some utility companies also run periodic radon awareness campaigns with discounted kits. It's worth checking your state's program before buying one at full price.

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I put a radon test near my sump pump. Is that a good location?

Placing a test near a sump pit or pump can give you a higher reading than your typical breathing zone, which may or may not reflect your actual exposure. For a general test of your apartment's air, place it in a room you spend significant time in - bedroom, living area - not right next to a known radon entry point. Even so, knowing the level near the sump pit is useful data.

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The lab says my test result has a margin of error. How much should I trust the number?

Short-term charcoal tests typically have a lab-reported measurement uncertainty of plus or minus 10-20%. That means a result of 4.5 pCi/L could realistically be anywhere from about 3.6 to 5.4. At marginal readings right around 4.0, this uncertainty matters - it's one reason to run a second test or use a long-term monitor to confirm. At clearly elevated levels, the uncertainty doesn't change the decision to act.

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My landlord says the test they ran was a short-term test in December and it showed 3.9. Should I trust that?

A single short-term test is a starting point, not a definitive answer. December (heating season) tends to show higher radon, which is actually the more conservative scenario. A result of 3.9 in winter is likely near or at typical peak conditions. That's right at the EPA's consideration range. It's not dramatically high, but it's not nothing - I'd track it with a continuous monitor if you're staying long-term.

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I placed a radon test in my closet. Will that give me a useful reading?

Closets are generally not where you spend time breathing, and air circulation there may differ from your main living space. A radon test in a closet doesn't tell you much about your actual exposure. Redo it in a bedroom or living room - somewhere you spend consistent time - at a height of about 20 inches to 6 feet off the floor.

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My landlord tested a different unit in the building and it came back below 4.0. They're using that to say my unit is fine. Should I believe them?

No. Radon levels vary unit by unit - different floor levels, different construction details, different pressure dynamics. One unit's test result tells you nothing about another unit. If you want to know your exposure, your unit needs to be tested.

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My landlord says they tested three years ago and radon was fine. Do they have to test again?

Generally, no law requires periodic re-testing unless your state has specific requirements. But a three-year-old test result doesn't warranty current conditions. If you want to know what you're breathing now, do your own test - don't rely on old results from a prior tenancy.

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My landlord is a management company with hundreds of units. Who do I talk to about radon?

Put your concern in writing - email the property manager directly and CC their maintenance department if you have that contact. Ask specifically for documentation of any prior radon testing and their plan to address your reading. Large property management companies often have legal and maintenance protocols; a written complaint creates a paper trail and tends to get taken more seriously than a verbal request.

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My landlord said they'd fix the radon and then never did. What can I document to protect myself?

Keep copies of every communication - emails, texts, voicemails. Take screenshots of your radon monitor readings with timestamps. Write a licensed letter to the landlord reiterating the elevated reading and requesting mitigation with a specific deadline. If they still don't act, your documented paper trail is what you'll need if you pursue a formal complaint or legal remedy.

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Is there a government agency I can report my landlord to for not fixing radon?

Your state radon office and local health department are the best starting points. Some states have formal complaint processes for radon-related habitability issues. HUD has guidance about radon in federally subsidized housing. Code enforcement offices in some municipalities also handle habitability complaints. The right agency depends on your state and housing type.

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I live in Section 8 / HUD-subsidized housing and the radon is high. Do I have extra protections?

Yes, potentially. HUD has issued guidance that elevated radon can constitute a habitability issue in federally assisted housing. Your housing authority has obligations under federal guidelines. Contact your local HUD office or housing authority and document the elevated readings in writing. HUD's radon guidance gives you more leverage than a typical market-rate tenant might have.

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My landlord says they'll fix the radon "eventually" but won't give a timeline. What should I do?

"Eventually" isn't a plan. Ask for a specific date in writing. Frame it as a health matter and reference the EPA's 4.0 pCi/L action level. If they won't commit to a timeline, escalate to your state radon office or health department. Landlords who feel external accountability tends to move faster.

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The radon mitigation fan in my rental apartment is loud and it runs all the time. Is that normal?

Yes, radon fans are designed to run continuously - stopping and starting would undermine the consistent negative pressure that keeps radon out. Most fans are relatively quiet, but the sound level varies by model and how it's installed. A low hum is normal; a grinding or rattling sound might indicate the fan needs service. Let your landlord know if the sound has changed significantly.

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My landlord tested before I moved in and gave me the results showing 3.2 pCi/L. Now two years later I tested and got 5.8. Who pays for mitigation?

The landlord is responsible for the physical mitigation system - that's a structural modification to the building. Present your current test results in writing and request mitigation. The fact that levels changed since the prior test is exactly why ongoing monitoring matters. The landlord's old test doesn't negate your current one.

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What if my landlord lives in the same building as me and they're also affected by the radon? Does that change anything?

It changes the dynamic in that your landlord is personally experiencing the same risk, which often makes them more motivated to act. The legal framework is the same, but a shared-interest conversation is often more productive. Approach it as something you're both dealing with together rather than an adversarial demand.

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My landlord mitigated the radon and said the system is working. But they won't give me the post-mitigation test results. Is that a red flag?

Yes. Post-mitigation test results are the proof the system is actually doing what it's supposed to. A landlord who won't share those results either doesn't have them (meaning post-mitigation testing wasn't done) or knows the results weren't as good as hoped. Either way, that's a reason to run your own test and document the results.

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I asked my landlord about radon and they got defensive and threatened to raise my rent. What do I do?

That part should be handled through the transaction, lease, or property-management process, not as contract or lease advice from a mitigation contractor. The radon side is more straightforward: confirm the result if appropriate, understand whether an existing system works, and decide whether mitigation, passive activation, repair, or follow-up testing is needed for the specific property. A buyer, seller, tenant, or landlord should talk with the appropriate real estate, legal, property-management, or housing contact about deadlines, credits, contract rights, or lease obligations. Bill can help explain what the mitigation work would involve and what property details should be checked.

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My landlord's insurance company flagged radon as a liability issue. Is that true?

It's increasingly true that insurance companies are paying attention to environmental hazards like radon, particularly in commercial or multi-family properties. That can actually work in your favor as a tenant - a landlord who has been flagged by their insurer has more motivation to address it. If you're in a dispute, it might be worth noting to the landlord that their liability exposure increases the longer elevated radon goes unaddressed.

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I live in a basement apartment with a sump pit in the closet. Could that be why radon is so high?

Almost certainly yes, at least in part. Sump pits are open connections directly to the soil and groundwater below your home - they're one of the highest-radon-entry pathways in any basement. If your pit doesn't have a sealed lid, radon is flowing straight up into your air. A sealed sump pit lid is a basic first step, though a full mitigation system usually includes addressing the sump as well.

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My basement apartment has 7 pCi/L. The landlord says it meets code. Is 7 pCi/L ever okay?

No building code "approves" 7 pCi/L as an acceptable level - the EPA recommends fixing at 4.0, and 7 is significantly above that. If a landlord is claiming this "meets code," they're misrepresenting the situation. The EPA's action level is not a legal code in most places, but it is the standard of care. 7 pCi/L is a level that warrants mitigation.

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I live in a garden-level apartment. Is that different from a true basement for radon purposes?

Not meaningfully. A garden-level unit is partially below grade - the floor or lower walls are in contact with or very close to the soil. Radon entry dynamics are similar to a full basement. In terms of radon risk, treat it the same as a basement and test accordingly.

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I'm 6 months pregnant and living in a basement apartment with 4.6 pCi/L radon. What should I do?

First, radon's risk is cumulative from long-term exposure - six months of slightly elevated exposure is not an acute emergency. Even so, 4.6 is above the EPA action level, and pregnancy is a reasonable time to want to reduce all unnecessary health risks. Bring the test result to your landlord in writing and request mitigation. For any specific concerns about health impacts on your pregnancy, talk to your OB. We can also talk through the numbers and what typical mitigation looks like if that's helpful.

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I've been renting my basement apartment for 3 years. Just found out radon is 6.0. Am I at risk?

Six pCi/L for three years is meaningful cumulative exposure. Radon risk is real and proportional to the level and duration of exposure. Even so, radon causes lung cancer over many years of ongoing exposure - you're not facing an acute medical event. What you should do now is get mitigation moving as quickly as possible to reduce your ongoing exposure, and mention your exposure history to your doctor at your next visit so it's documented. You can't undo the past three years, but reducing exposure from this point forward matters.

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My basement apartment floods occasionally. Does that affect radon?

Wet basements and radon don't have a straightforward relationship - high moisture can actually slow some radon entry in certain situations, but it can also degrade sealing materials and create other structural issues. A wet basement with cracks, gaps, and a sump pit is generally a higher radon risk regardless. Flooding and radon are both problems worth addressing.

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I'm renting a basement apartment and the previous tenant left. Is radon worse when an apartment is unoccupied?

Radon can accumulate in an unoccupied space faster because there's no ventilation from opening doors and windows and no HVAC running at full occupancy levels. A test right after move-in, especially if the space was closed up for a while, may actually show slightly elevated levels that will settle with normal occupancy and ventilation. Let the space air out and then test under normal closed-house conditions for the most realistic result.

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My basement apartment has a dirt floor in part of the utility area. Is that a major radon risk?

Yes, an exposed earth floor is a significant radon entry point - soil contact is direct and there's no concrete barrier. That's one of the situations where radon entry is essentially unrestricted. If you're renting a space with exposed dirt, that should be disclosed, and it's worth having tested promptly.

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I live in a basement apartment in an older building from the 1940s. Does the age of the building matter for radon?

Older buildings often have more cracks, gaps, and less sealing than newer construction, which can mean more radon entry points. But radon entry is driven by pressure dynamics, not just age - some old buildings happen to be in lower-radon geology and test fine. Age is a reason to test, not a warranty of a problem.

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My basement apartment shares a foundation wall with the garage. Does that increase radon risk?

It can. Garages often have less sealing than living spaces, and attached garages can be another pathway for soil gases to enter the building. A shared wall with the garage is worth noting, but the test result will tell you more than speculation about building features.

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I'm in a basement apartment and the radon is 4.2 in the bedroom but 2.1 in the main room. Which number matters more?

The bedroom matters more because that's where you spend the most concentrated time - especially sleeping eight hours a night. Cumulative exposure is based on how long you're in a space and at what level. The bedroom is often the most important room to protect.

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My basement apartment has a dehumidifier running all the time. Does that help with radon?

No. Dehumidifiers reduce moisture in the air - they don't filter, dilute, or remove radon gas. Radon is not related to humidity. Running a dehumidifier won't change your radon levels in any meaningful way.

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I live in a basement unit and my landlord put a vent fan in the window to "get rid of" the radon. Does that work?

Window fans can provide some dilution ventilation, which can reduce radon levels somewhat - but it's not a reliable or consistent solution. It depends on airflow direction, whether the fan is pulling or pushing, and whether you keep it running. It's also impractical in cold climates to run open windows year-round. A proper sub-slab depressurization system is the engineered solution that consistently works.

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Are basement apartments with finished floors better or worse for radon than unfinished concrete?

A finished floor with well-sealed materials reduces direct soil contact and can slow radon entry at the surface, but radon still enters through cracks, floor-wall joints, pipes, and other penetrations. Finished floors help marginally but aren't a substitute for testing or mitigation.

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I'm a college student renting a basement apartment. The radon is 5.0 pCi/L. What can I do?

5.0 pCi/L is above the EPA action level and worth addressing. As a tenant, you can't install mitigation yourself, but you absolutely can put your landlord on notice in writing with your test result and ask them to address it. If your landlord is unresponsive, check whether your university has a tenant advocacy resource - many universities do, specifically for students dealing with off-campus housing issues.

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I'm renting a house with roommates off-campus. The basement radon is high. Who's responsible?

The landlord is responsible for the building's habitability, including radon. As tenants, you all have the same standing to request mitigation. It's often most effective to make the request as a group - all roommates signing a written request to the landlord carries more weight than one person asking. Document the test result and the date you reported it.

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My college dorm is in a basement-level room. Should I buy a radon monitor?

If your dorm room is at or below grade, it's a reasonable thing to check. Most universities have buildings that have been tested, and some have mitigation systems. Ask your campus housing office whether their buildings have been tested for radon - many will have records. If they can't give you a clear answer, a consumer monitor in your room will tell you what you need to know.

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I'm subletting a basement apartment for one semester. Is it worth worrying about radon for just a few months?

Radon risk is cumulative over years, so four months at elevated levels is a small fraction of a lifetime. Even so, there's no reason to be cavalier about it - if the space has very high levels, even a semester matters incrementally. A quick short-term test will tell you what you're dealing with. If it's moderate, it's probably not worth a major fight for a short sublet. If it's very high - 8, 10, 12 pCi/L - that's worth knowing and pushing back on even for a short stay.

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I'm renting a basement studio apartment near campus. The landlord is unresponsive. What are my options?

Put your test result in writing via email or text so you have documentation. Contact your university's off-campus housing office or student legal services - many schools have resources specifically for this. Your city or county health department may be able to apply pressure. And if the landlord continues to ignore it, evaluate whether staying in that unit is worth the ongoing exposure.

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I'm in a college house with five roommates. The basement radon is 8.0. We all use the basement as a common room. Is that bad?

8.0 pCi/L is twice the EPA action level, and using it as a common room significantly increases everyone's cumulative exposure. Stop spending time in the basement as common space until it's addressed - use other areas of the house. Collectively report to your landlord in writing. If you have a student tenant advocacy resource at your school, this is exactly the kind of situation they handle.

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My landlord owns a dozen off-campus rental houses and says they "never have radon problems." Should I take their word for it?

No. "We've never had problems" usually means "we've never tested." Properties that have never been tested haven't identified problems - that's not the same as not having them. Ask for actual test documentation, not a landlord's general sense that everything is fine.

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I'm moving into a student rental in the fall. Should I ask about radon before I sign the lease?

Yes. Ask specifically whether the property has been tested, and if so, request a copy of the results. Ask about the floor level of your room if you're in a multi-story house. If the landlord doesn't have test results and your room will be at or below grade, plan to test shortly after moving in.

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My university housing department tested the dorms and says radon is fine. But my building is old. Should I trust them?

It's reasonable to trust a university that has done actual documented testing. Ask for the specific results for your building and floor - not just a general "we tested and it's fine" statement. If they can provide documented results from the last few years, that's meaningful. If they're vague about when or where they tested, that's less reassuring.

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I'm a first-year student moving into a basement single. My parents are worried about radon. What should I tell them?

Tell them the worry is legitimate - basement spaces can have elevated radon and it's worth knowing the levels. The practical answer is to pick up an inexpensive short-term test kit or a continuous monitor for your room. That turns an unknown into a known, and if the levels are fine you'll all have peace of mind. If they're elevated, you have something to bring to your housing office.

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Our landlord is letting us use the unfinished basement for storage and hanging out. Radon is 11 pCi/L down there. Do I need to tell my roommates?

Yes, absolutely tell them. 11 pCi/L is a significant level, and everyone who spends time there has a right to know. Stop spending time in the basement, document the reading, and report it to your landlord in writing as a group. This level warrants real urgency from your landlord, not a casual response.

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I'm an RA in a dorm and a student told me their basement-level room might have high radon. What should I do?

Take it seriously and escalate through official channels - your housing office and facilities management. Request documentation of radon testing for that building. If there's no recent test data, ask for a test to be performed. A student shouldn't be breathing significantly elevated radon in housing provided by the institution, and it's your job as RA to make sure the concern gets to the right people.

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My off-campus landlord lives out of state and is basically unreachable. What are my options for the radon issue?

Try every contact method you have - email, text, the contact info on your lease - and document all attempts. An out-of-state landlord typically has a local property manager or contact; check your lease for that. If you can't reach anyone, contact your city or county housing code enforcement or health department and file a formal complaint. That usually triggers an official response even when the landlord is non-responsive.

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What's the best radon monitor for a renter who might move every year or two?

A portable continuous monitor is ideal for renters. The Airthings Wave series connects to your phone via Bluetooth and is easy to move. The RadonEye RD200 is another solid option with good accuracy. Both are compact, don't require installation, and you take them with you when you move. The investment makes sense if you'll be renting for several years.

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Can I take my radon monitor with me when I move to a new apartment?

Yes. Consumer radon monitors are standalone devices - there's no installation required. You unplug them or remove the batteries, pack them with your stuff, and set them up in the new place. One good monitor can serve you through multiple rentals over many years.

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My Airthings app shows a new reading every hour. Which number should I look at?

Look at the long-term average, not the hourly reading. Radon levels fluctuate significantly hour to hour based on pressure changes, weather, and ventilation. The long-term average (typically the 30-day or 90-day average shown in the app) is what gives you a meaningful picture of your typical exposure.

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I'm a renter and I'm trying to decide between the Airthings Wave Plus and the RadonEye. Which should I get?

Both are solid for renters. The Airthings Wave Plus also monitors humidity, CO2, and other air quality factors in addition to radon, which gives you a fuller picture of your air. The RadonEye RD200 tends to have a faster update cycle and is often preferred for its more granular radon data specifically. If radon is your main concern, RadonEye; if you want broader air quality awareness, Airthings.

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How long does it take for a radon monitor to give me an accurate reading?

Most continuous monitors need a few weeks to build a reliable long-term average. The first few days of readings can be more volatile and less meaningful. After 30 days, the long-term average displayed in the app or on the device is considered reasonably accurate. For EPA comparison purposes, a 90-day average is considered the gold standard for long-term testing.

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My radon monitor shows high readings in the early morning. Is it actually higher then?

Yes, often. Radon tends to peak in early morning hours when buildings have been closed overnight, ventilation is minimal, and soil pressure dynamics favor radon entry. This is normal behavior - it's not a malfunction. Your long-term average is more meaningful than the morning peak.

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Can I use one radon monitor for multiple apartments by moving it between them?

You can, but it takes time to get a meaningful reading in each location. If you're moving between units frequently, you'd spend weeks in each place before the average stabilizes. For a permanent residence, a monitor running continuously is the right approach. For quick assessments of multiple spaces, short-term charcoal canister tests are faster and cheaper.

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Do I need more than one radon monitor in my apartment?

For most apartments, one monitor placed in the lowest level you spend time in is sufficient. If you have a two-level unit with a significant grade change between floors, testing both levels can be informative. But for a typical single-floor apartment, one monitor gives you a good picture.

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My landlord says my radon monitor is "not licensed" and their test is the official one. Who's right?

Consumer monitors aren't "licensed" in the same way professional measurement devices are, but good ones are validated and accurate. Your monitor's data is valid and meaningful. A landlord can't simply dismiss a consumer monitor reading - especially if it's a reputable device showing consistently elevated levels. If there's a dispute, a professional test by a licensed radon measurement professional settles the question definitively.

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My Airthings battery died and the reading reset. Does that mean I lost all my data?

Airthings devices sync data to the cloud via the app. If your phone was syncing regularly, your historical data should still be in the app. Some data may be lost if the device was offline for a while and hadn't synced. This is one reason to check the app periodically rather than just leaving the device running unattended for months.

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Can radon levels in my apartment change seasonally on my monitor?

Yes, and that's expected. Radon typically rises in winter when buildings are closed up and HVAC pulls more air from below, and tends to be lower in summer with more ventilation. Your monitor will show you this seasonal pattern over time. The annual long-term average is your best estimate of typical exposure.

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I put my radon monitor in my bedroom closet for better placement. Is that okay?

Closets generally have less air circulation than the main room, which can mean slightly different radon levels than your breathing zone. Better to put it on a shelf, nightstand, or dresser in the bedroom itself - somewhere you spend your sleeping hours. The goal is to monitor what you're actually breathing.

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My Airthings shows 3.9 pCi/L but the professional test my landlord did shows 2.7. Why the difference?

Short-term professional tests and continuous monitors can differ based on timing, test duration, and placement. A 48-hour professional test captures a specific window; your continuous monitor shows a running average. Differences in placement can also matter. Neither is necessarily wrong - they're measuring different things over different timeframes. At these levels, both readings are in the below-4.0 range, though the difference in the readings is worth noting.

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I'm in a 6-unit condo building. One unit has high radon. Does that mean all units have a problem?

Not necessarily, but it's a reasonable concern. In a building with shared foundations and airflow pathways, radon in one unit can indicate conditions that exist throughout the building. Floor level matters a lot - lower units are at higher risk. All ground-floor and basement units should be tested, not just the one that flagged first.

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I live on the 3rd floor of a 5-story apartment building. Do I need to worry about radon?

Third floor in a five-story building - radon is unlikely to be a significant issue at that height. Radon concentrates at the lowest levels and dissipates with height. Most third-floor units in multi-story buildings have very low radon levels. Unless the building has unusual construction or you're getting strange readings, this isn't a priority concern.

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My high-rise apartment is on the 15th floor. Is radon even a thing up there?

At the 15th floor, radon is not a meaningful concern. By that height, outdoor air dilution and building air exchange make radon levels effectively negligible in the living space. Radon is a ground-level issue.

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My downstairs neighbor got a high radon reading. Should I be worried about my unit above theirs?

Probably not to the same degree. Radon tends to move from the ground upward and dissipate - your unit above theirs is likely at significantly lower concentration. Even so, if the building has poor air sealing between floors or a shared HVAC system, there can be some distribution. A quick test in your own unit will give you certainty.

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Can a radon mitigation system in one unit of a multi-unit building protect all units?

A system installed in one unit typically protects that unit specifically. In multi-unit buildings, mitigation systems may be designed to address radon across multiple units if they share sub-slab space and the system is designed for the full footprint. Building-wide or multi-unit mitigation requires coordination and proper design - it's not something one tenant can install and have it benefit everyone.

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Our apartment building manager said they're going to install a radon system in the basement "utility area." Will that protect my ground-floor apartment?

A system in the utility area may help if it addresses the same sub-slab zone as your unit, but it depends entirely on how the building's foundation is constructed and whether the system is designed to create pressure relief under your unit specifically. Ask for post-mitigation test results in your actual living space - that's the only way to confirm your unit is protected.

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The building I'm buying into as a condo buyer has a ground-floor unit with known radon. Should that affect my offer on a second-floor unit?

Probably not significantly for a second-floor unit. If you're buying a second-floor unit, radon is unlikely to be elevated at your level. The ground-floor unit's radon issue is a building concern, but for your unit specifically, a test of the actual space at closing is the right way to verify the air you'll be breathing.

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I'm renting in a townhouse with a finished basement unit below me. My floors are the ground level. Can radon from below migrate up to me?

Radon in the unit below yours is primarily that tenant's concern - radon doesn't typically migrate upward in significant concentrations through occupied floor space. But if your ground-level unit is directly over the soil or has penetrations to the sub-slab area, you could have your own independent radon entry. Test your unit on its own merits.

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I've been renting a basement apartment for 5 years and just found out radon is 6.0 pCi/L. What do I do about my health?

For any health concerns related to past radon exposure, have a conversation with your doctor - let them know your approximate exposure history so it's documented. From a practical standpoint, you can't undo past exposure, but you can reduce future exposure starting today. Get mitigation in motion as quickly as possible. The risk from radon is cumulative and ongoing; lowering your levels now matters.

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I keep getting headaches in my basement apartment. Could it be radon?

Radon does not cause headaches, sore throats, dizziness, or any short-term symptoms. It's an odorless, colorless gas that creates risk only through long-term radiation exposure to lung tissue. If you're having headaches in your basement apartment, look at other causes - poor ventilation, carbon monoxide, mold, humidity, or other factors. Get a CO detector if you don't have one, and see your doctor about the headaches.

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My apartment smells musty and I'm worried it's radon. Can I smell radon?

No. Radon is completely odorless, tasteless, and invisible - there's no way to detect it with your senses. The musty smell is likely moisture, mold, or mildew, which are common in basement spaces. Both mold and radon can exist together in a basement, and both are worth addressing, but they're completely different problems with different solutions.

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I'm a heavy smoker and I live in a basement apartment with 5.0 pCi/L radon. Should I be extra worried?

Yes. Radon exposure and smoking significantly compound each other's lung cancer risk - the combination is far more dangerous than either alone. If you smoke and live in a high-radon environment, your risk is substantially elevated. Getting the radon addressed is even more important in your situation. For anything related to your personal health risk, your doctor is the right person to talk to.

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My child has asthma and we live in a ground-floor apartment with 4.8 pCi/L. Is radon making the asthma worse?

Radon doesn't cause or worsen asthma - asthma is a reactive airway condition and radon doesn't directly trigger it. However, the long-term lung cancer risk from radon is real, and with a child in the home, addressing elevated radon makes sense regardless of the asthma. For the asthma itself, look at humidity, mold, dust, and allergen sources in the apartment.

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Is radon worse for pregnant women specifically?

The primary concern with radon is long-term lung cancer risk from radiation exposure - that applies to everyone, including pregnant women. There isn't strong evidence that radon poses distinct risks to a developing fetus beyond the general concern about elevated radiation exposure to the mother. For specific guidance during pregnancy, your OB or midwife is the right source. Reducing unnecessary radon exposure during pregnancy is a reasonable precaution.

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My elderly mother lives in a basement apartment and I just found out the radon is 5.5. Should I move her?

At 5.5 pCi/L, mitigation is warranted. Whether to move her while mitigation is arranged depends on the feasibility of quick mitigation and her overall health. If the landlord can get a mitigation system installed quickly, that may be preferable to the disruption of moving. If the landlord is unresponsive, that changes the calculus. Her doctor can help you weigh the health considerations based on her individual situation.

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I have a radon level of 3.6 in my apartment and I'm a non-smoker. What's my actual cancer risk?

3.6 pCi/L is below the EPA's 4.0 action level but above typical outdoor background. The EPA estimates the lifetime lung cancer risk at 3.6 pCi/L for a non-smoker at roughly 1-2 per 100 people over a lifetime of exposure - which is lower than the risk at higher levels but not zero. The EPA's guidance to consider mitigation between 2.0 and 4.0 is based on this kind of risk calculation. It's a real but modest risk at that level.

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My landlord told me that radon isn't dangerous "unless you're a miner." Is that true?

That's outdated information based on early radon research, which was primarily conducted on underground miners. Subsequent decades of research have firmly established that residential radon exposure increases lung cancer risk - it's the leading environmental cause of lung cancer and the second leading cause overall after smoking. The EPA, WHO, and every major health organization agree on this. The "miner myth" isn't accurate.

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I've been reading about radon online and now I'm anxious about my apartment. How worried should I actually be?

The risk from radon is real, but it's proportional to your levels and your duration of exposure. If you haven't tested yet, testing is the most useful thing you can do - it converts anxiety about an unknown into actionable information. If your levels are low, you can relax. If they're elevated, you can take steps. The worst position is not knowing and continuing to worry. Test, then decide based on what you find.

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I live in a mobile home. Can I have a radon problem?

Yes. If your mobile home is sited on the ground - whether on a slab, a crawl space, or directly on a frame - it can have radon entry points just like any structure close to the soil. Manufactured homes have been found with elevated radon levels in the same kinds of locations as conventional homes.

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Can I get radon mitigation for a manufactured home?

Yes, mitigation is possible in manufactured homes, though the approach differs from a traditional slab or basement home. It often involves addressing the crawl space or under-floor area with ventilation or a sub-membrane depressurization system. The specifics depend on how your home is constructed and sited.

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My mobile home is on a slab. How do I test for radon?

The same way you'd test any home - a short-term charcoal canister test or a continuous monitor placed in the lowest living area. Slab-on-grade manufactured homes can have radon entering through the slab and floor penetrations just like a site-built home. Place the test in your main living area at about 20 inches off the floor, following the standard closed-house protocol.

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My manufactured home has a crawl space. Is the radon risk higher?

Crawl spaces can be significant radon entry zones because there's often a soil surface beneath with limited sealing. Manufactured homes with open crawl spaces are sometimes at higher risk. A vapor barrier and proper ventilation of the crawl space can help, though full mitigation may require specific measures depending on the setup.

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I rent a mobile home in a park. The landlord says they don't test mobile homes for radon. Do I have any options?

You can test your own home with a consumer test kit or monitor - you don't need the landlord's permission to find out what the air inside your home looks like. If levels are elevated, you bring that to the landlord, the same as any rental. Mobile home park landlords have the same general habitability obligations as other landlords.

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I bought a used manufactured home and it's on a rented lot. Do I test for radon?

Yes. When you move a manufactured home or occupy a home that's been sited somewhere for a while, testing is the first thing to do. Your radon levels depend on the geology of the land your home sits on, not just the structure itself. Test early and test at the lowest level of the home.

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Can radon enter a mobile home through the floor vents and ductwork?

Radon primarily enters through gaps and penetrations at the floor level, not through the duct system itself. However, if your HVAC draws air from under the floor or from a crawl space, that can contribute to distribution. The main entry pathways are usually the floor-to-wall interface, pipe penetrations, and any gaps in the floor structure.

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My manufactured home has plastic sheeting under the floor. Does that help with radon?

A ground vapor barrier (plastic sheeting) can reduce radon entry somewhat compared to bare soil, but it's not a reliable mitigation strategy on its own. Tears, gaps, and unsealed edges allow radon to pass through. A proper sub-membrane depressurization system is a more engineered approach for a crawl space situation.

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I'm considering two apartments - one on the second floor and one in the basement. Should radon factor into my decision?

It's a legitimate factor, especially for long-term occupancy. Basement apartments tend to have higher radon potential than second-floor units. If both are otherwise equal, the second floor is the lower-radon choice. If the basement apartment has an existing mitigation system with documented results below 4.0, that risk may already be managed - ask for the test results.

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My lease is up for renewal and I want to make radon testing a condition. How do I approach that?

Before you sign the renewal, put your request in writing. Something like: "As a condition of renewing, I'd like a current radon test completed in the unit, and results shared with me. If levels are at or above 4.0 pCi/L, I'd like a mitigation system installed prior to signing." Landlords who want to keep a good tenant will often agree to reasonable requests. Get any agreement in the lease addendum, not just a verbal promise.

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The radon in my apartment is 4.2. I'm planning to move in 8 months anyway. Should I bother pushing my landlord now?

Eight months at 4.2 pCi/L is real cumulative exposure, and the next tenant will face the same issue. It's worth sending your landlord a written notice with the test result - even if mitigation doesn't happen before you leave, you've documented the issue and given the landlord notice, which matters for future tenants and potential liability. For your own current exposure, spending more time on higher floors and ensuring good ventilation helps at the margins.

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I found a great apartment but it's in a basement and I'm worried about radon. Should I ask for a radon test before signing?

Yes, ask before you sign. Request the most recent test results. If the landlord doesn't have any, ask if they'll test as a condition of your signing. If they refuse both requests, factor that into your decision - a landlord who won't provide basic air quality information before you commit to a basement apartment tells you something about how they'll handle concerns after you're locked into a lease.

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I'm about to move out of a high-radon apartment. Should I document the radon level before I leave?

Yes, for two reasons. First, your future landlord may ask about your previous exposure if you raise health questions. Second, if the current landlord tries to deny the problem later or a future tenant asks about the history, your documented record provides evidence. Take screenshots of your monitor readings with dates, or mail yourself a written record that creates a timestamp.

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I looked up my future apartment's address and found an old radon test in a database. It showed 6.5 ten years ago. What should I ask?

Ask the landlord directly whether they've retested since, and if so, ask for the results. If they say they mitigated, ask for the post-mitigation test. If the 6.5 result is the most recent data and nothing was done about it, that's a red flag. A decade-old unmitigated result at 6.5 is not reassuring - test before you commit.

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I'm in a rental and my neighbor's mitigation system is making noise through the shared wall. Is that a sign their system is working or failing?

Radon mitigation fans make a low hum when working normally. Vibrations or noise transmitted through shared walls are typically installation issues (poor vibration isolation) rather than a sign the fan is failing. It's worth letting both your landlord and neighbor's landlord know - a well-mounted fan should be largely quiet. It doesn't necessarily mean the system isn't working.

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What are the most important things I can do as a renter to reduce radon in my apartment right now?

You have limited control over the building structure, but you can: test to know your actual levels, report elevated results to your landlord in writing, increase ventilation where practical (open windows when weather allows), seal visible cracks and gaps in floors and walls with appropriate caulk, and keep any sump pit covered. These are mitigation-lite measures - not a substitute for a real system, but not nothing either.

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Can I seal floor cracks myself to reduce radon in my rental?

You can seal visible floor and wall cracks with polyurethane or epoxy caulk, and it may modestly help. However, sealing alone is not recognized as effective radon mitigation because radon enters through dozens of pathways, many not visible. It's a reasonable supplemental step but not a solution on its own.

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Will opening my windows every day help with the radon in my apartment?

Ventilation can dilute radon and temporarily reduce levels - it's not nothing. But it's not a reliable control strategy, especially in climates where you can't practically open windows year-round. Levels typically rebound quickly when windows close. Opening windows while you sleep in warm weather is a practical harm-reduction measure, not a solution.

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Is a HEPA air purifier helpful for radon?

No. HEPA filters capture particles - they don't filter radon gas. Radon is a gas, not a particulate matter. Air purifiers of any kind don't reduce radon levels. This is a common misconception worth clearing up.

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Can I install a radon mitigation system myself in my rental?

No. Mitigation requires drilling through the foundation slab and installing a fan system - that's a structural modification to the building. You can't and shouldn't do that without the property owner's involvement. It's the landlord's building; mitigation is their responsibility.

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I put a box fan in my basement apartment to increase airflow. Does that help?

Increased air exchange can dilute radon somewhat, but a box fan alone doesn't do it in a controlled way. If the fan is pulling outdoor air in and pushing basement air out, there's some dilution effect. But fan placement, direction, and how much outdoor air is actually being brought in all affect how much it helps. It's a partial measure, not a solution.

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My landlord offered to do the radon mitigation themselves rather than hire a professional. Should I be okay with that?

It depends on what they mean. A landlord who has gotten proper training and certification in radon mitigation can technically do the work. But if they mean "I'll stick a pipe through the floor and see what happens," that's not the same thing. A properly designed and installed system requires understanding of sub-slab pressure dynamics and proper fan selection. Post-mitigation testing is essential to verify it worked. Ask that the work be done by or verified by a licensed radon mitigation contractor.

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How long does radon mitigation typically take to install in an apartment?

A standard sub-slab depressurization system in a typical apartment or home takes most of a day to install. The contractor drills a hole in the slab, installs a pipe and fan, and routes it to the exterior. Post-mitigation testing typically follows 24 hours or more after installation. The whole process from installation to verified results is usually about a week.

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After a mitigation system is installed in my rental, how long until the radon levels go down?

Radon levels typically drop significantly within 24-48 hours of a properly installed system. A test run after the system is up and running for a day or two will show dramatically lower levels if the system is working correctly. Continuous monitors will show you the change in real time.

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I moved into an apartment that already had a mitigation system. The previous tenant left a radon monitor that shows 1.8 pCi/L. Can I trust that reading?

A continuous monitor left by a previous tenant that's showing 1.8 pCi/L is a reasonable indicator that the system is working. But you don't know when the monitor was last checked, whether it's been calibrated, or whether it's functioning properly. Consider running your own short-term test to verify the reading independently, especially if you're going to be living there long-term.

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What if my landlord installs mitigation but it doesn't work? What are my options?

A post-mitigation test will reveal whether the system worked. If levels are still above 4.0, the system needs to be evaluated - it may need a larger fan, a different installation point, or additional suction points. Share the post-mitigation test result with your landlord and request the contractor come back to assess. A responsible contractor and landlord will follow through until the system achieves results.

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I just moved in and my Airthings is going crazy - showing 14 pCi/L. Is that right?

It could be an accurate reading, or it could be the initial measurement period before the monitor's algorithm stabilizes. However, 14 pCi/L is a level that warrants immediate attention regardless. Open windows to ventilate, document the reading, and contact your landlord the same day in writing. Don't wait. If you have the option to stay elsewhere while this is investigated, that's worth considering for a reading that high.

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My landlord said they "aired out" the apartment before I moved in. Does that change the radon?

Ventilating a space before occupancy can temporarily lower radon levels, but once normal occupancy patterns resume - windows closed, HVAC running - levels return to their baseline. An "aired out" result would underestimate your actual living conditions. Test now under normal conditions with windows and doors closed.

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I'm renting and the unit below me has a mitigation system. Am I benefiting from it?

Possibly, but you shouldn't assume so. Mitigation systems are designed for the unit where they're installed. Your unit has its own air dynamics and radon entry pathways. Test your own unit independently to know what you're breathing.

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I'm moving to a new state and not sure about radon levels there. How do I find out?

The EPA publishes radon zone maps by county - Zone 1 counties have the highest average radon potential. Your new state will also have a radon program under the health or environmental department with more detailed local information. But zone maps are averages - only testing your actual unit tells you what you're breathing in that specific home.

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My landlord said the building was "built to radon standards." What does that mean?

Radon-resistant new construction (RRNC) features - passive vent pipes, sealed foundations, sub-slab gravel layers - are included in some buildings built to current standards. If present, these features reduce radon entry compared to a building without them, and adding a fan to the passive pipe is a cheap mitigation upgrade if needed. "Built to radon standards" is not the same as "radon is not a problem" - a test is still needed to verify levels.

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I rent a room in a house. The radon monitor in the living room shows 3.5 but my bedroom is in the basement. Should I test there too?

Yes. Test where you actually sleep. Radon levels on the ground floor can be substantially different from levels in a basement bedroom. The living room monitor doesn't tell you what you're breathing during the eight hours a night you spend in your basement bedroom.

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I live in a vacation rental for 3 weeks every year. Should I worry about radon?

Three weeks per year is very low cumulative exposure. Radon risk scales with the amount of time spent in the space. For a vacation rental where you spend a few weeks annually, radon is not a meaningful health concern. It's worth knowing if it's dramatically elevated for your own peace of mind, but it's not a health priority at that occupancy level.

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I rent an Airbnb for a month. Should I test for radon?

A month is meaningful, especially if it's a basement-level space. A short-term test kit or a portable continuous monitor will give you a reading within a couple days. If levels are elevated, you can inform the host and choose to ventilate more aggressively or evaluate other options. For a one-month stay, you may not have much leverage over the property - but knowing is still better than not knowing.

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My landlord has a mitigation system but I notice the U-tube manometer looks the same on both sides. What does that mean?

An equal level in both sides of the U-tube manometer means no differential pressure is being created - the fan likely isn't operating or isn't drawing suction through the pipe. That system isn't working. Notify your landlord immediately that the manometer indicates no suction and have them contact the mitigation contractor to inspect the fan.

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Can radon in my basement apartment affect my pet's health?

The same lung cancer risk from radon that applies to people applies to dogs and cats that breathe the same air. Pets that spend significant time in low-lying areas or on the floor may have even more concentrated exposure. For specific concerns about your pet's health, a veterinarian is the right resource - but addressing elevated radon is good for everyone in the home, including animals.

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I rent a converted basement that was once a storage area. Could it have higher radon than a purpose-built basement apartment?

Possibly. Converted spaces may have more cracks, unfinished penetrations, and less sealing than purpose-built apartments. If the conversion was done primarily for livability (adding drywall, flooring) without attention to air sealing, the radon entry points may be more numerous. Test it.

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My apartment has a communal laundry room in the basement. Should I limit my time down there?

If the basement laundry room has elevated radon, your time down there contributes to your cumulative exposure. Most people spend only short periods in laundry rooms, which limits the overall impact. If you're already dealing with high radon in your unit, limiting unnecessary time in other basement areas is a reasonable precaution. Ask your landlord whether the common areas have been tested.

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I'm renting a basement apartment and the radon is 9.4. My landlord is taking weeks to respond. Who else can I call?

At 9.4 pCi/L you're more than twice the EPA action level - escalate now. Contact your local health department or code enforcement office and file a formal complaint. If your state has a radon program, call them. Document everything you've sent the landlord and the dates. At these levels, you also have the option of moving out for your health - a habitability dispute this clear gives you real legal standing.

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I'm renting a detached garage apartment. Is radon a concern?

If the garage apartment is at or near ground level and has a concrete slab or floor that sits on soil, yes - the radon dynamics are similar to any other low-level structure. Garage conversions vary a lot in construction quality and sealing. Test it the same way you'd test any basement-level space.

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My apartment has cracks in the concrete floor that have been there since I moved in. Should I caulk them?

It's a reasonable step. Visible floor cracks are documented radon entry pathways, and sealing them with polyurethane caulk is easy and inexpensive. It won't solve a significant radon problem on its own, but it's worth doing as part of a general approach to reducing entry points. Notify your landlord about the cracks as a maintenance matter as well.

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I've lived in my basement apartment for 10 years and just found out radon is 5.5. How do I process this?

First, understand that what's done is done - you can't change the past decade. The radon risk is real but it's cumulative and probabilistic - elevated radon increases the risk of lung cancer, it doesn't warranty it. What you do from this point forward matters. Get mitigation in motion as fast as you can. Mention your exposure history to your doctor at your next visit so it's documented. Then focus on reducing your ongoing exposure starting now.

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My landlord keeps saying they'll "look into getting a quote" for mitigation. That's been three months. What is a realistic timeline for mitigation?

Once a landlord actually engages a contractor, a radon mitigation system is typically installed within a few days to a couple of weeks depending on scheduling. The work itself takes a day. Three months of "getting a quote" is delay, not a timeline. Put your request in writing with a specific deadline - say, 30 days to have a contractor scheduled - and make clear you'll contact the health department if that deadline passes.

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I want to show my landlord how serious radon is. What's the best way to explain it to them?

Keep it simple: radon is the second leading cause of lung cancer in the United States, causing about 21,000 deaths per year according to the EPA. It's an odorless gas that comes up from the soil and concentrates in lower-level spaces. Fixing it is a one-time mechanical installation that typically lasts for years. The risk of not fixing it is real and ongoing. Most landlords, once they understand this, take it seriously - they're in the property for the long haul too.

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Can I get radon information specific to my area before I sign a lease in a new city?

Your new state's radon program website will have zone maps and guidance specific to your region. The EPA's radon zone map (available at epa.gov) shows county-level radon potential. High-radon zone counties don't warranty your specific unit will be elevated, and low-zone counties don't warranty it won't be - but it gives you a sense of the geology. Test after move-in regardless of the zone.

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I'm renting and my continuous monitor has been showing consistent levels over 4.0 for six weeks. Is that enough evidence to take to my landlord?

Six weeks of consistent readings over 4.0 is very solid evidence. Export or screenshot the historical data from your monitor app - the trend line showing consistent elevated levels over time is more compelling than a single snapshot. Present that to your landlord in writing along with a written request for mitigation. Consistency over time is hard to argue with.

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My landlord said they'll mitigate when I leave so they can "do it all at once." Is that reasonable?

No. Waiting to mitigate until you move out means you're exposed to elevated radon for the remainder of your tenancy. That's not a reasonable position. The mitigation benefits the current occupant as much as a future one. Push back - your health doesn't benefit from a future mitigation system.

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I told my landlord about high radon via a phone call. Is that enough?

Follow up every verbal conversation in writing - email or text. A phone call creates no record. "Per our call today, I'm confirming that I reported radon levels of [X] pCi/L in my unit and requested mitigation" - sent to the landlord immediately after the call - creates the paper trail you may need later.

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My landlord is a family member and we don't want to make it awkward. How do I bring up radon?

Approach it as information-sharing rather than a confrontation. "Hey, I got a radon test and the levels are a bit elevated - I figured you'd want to know since it's something that should be addressed in the building" tends to land better than leading with demands. Family landlords are often more willing to fix things once they understand the issue - the challenge is getting past the "I've never heard of this before" initial resistance.

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I'm renting a house with a crawl space instead of a basement. Is crawl space radon different?

Crawl spaces are a significant radon entry zone because soil beneath the home is largely exposed. Radon enters through the crawl space and migrates into the living area above through floor penetrations, ductwork, and unsealed gaps. The mitigation approach differs from a basement (often sub-membrane depressurization in the crawl space rather than sub-slab) but the concern is just as real.

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My landlord wants to use caulk and paint as the radon mitigation solution. Is that sufficient?

No. Sealants and paint are not recognized as effective radon mitigation by the EPA. They may reduce entry slightly at specific points but don't address the pressure dynamics that drive radon into the building. The standard effective solution is sub-slab depressurization with a fan - that's what reduces pressure beneath the slab so radon can't enter. Caulk is a supplement, not a solution.

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I rented out my basement to a tenant and now they're saying the radon is high. What do I do?

Take it seriously and ask for a copy of their test result. If the reading is at or above 4.0 pCi/L, arrange for a professional mitigation contractor to assess the space. You have a habitability obligation to your tenant. Acting promptly not only protects your tenant but also limits your liability. If you'd like to talk through what mitigation typically looks like for a basement rental, feel free to reach out.

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Is radon higher in a below-grade unit in winter or summer?

Generally higher in winter. Closed windows, sealed buildings, and heating systems that draw air from below all drive winter levels up. Summer often shows lower levels due to open windows and natural ventilation. This is why testing during heating season gives you a more conservative (higher) estimate of typical exposure.

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I heard radon can be worse during certain types of weather. Is that true?

Yes. Low-pressure weather systems can cause radon to spike temporarily - lower atmospheric pressure allows more soil gas to push up into buildings. Heavy rain can also saturate soil and force radon upward. These weather-related fluctuations are part of why short-term tests and hourly monitor readings can vary, and why long-term averages matter more than any single reading.

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My basement apartment has a wood subfloor over the concrete. Does that help with radon?

A wood subfloor adds a layer between you and the concrete, but it doesn't meaningfully reduce radon entry. Radon still comes up through the concrete, penetrations, and the gaps around the subfloor perimeter. A subfloor is not a barrier to radon gas in any practical sense.

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My landlord is willing to fix the radon but wants to do it cheaply with a single fan and minimal pipe. Should I be concerned?

System design matters. A system with too small a fan or a poorly placed suction point may not reduce levels adequately. The right system depends on sub-slab communication (whether suction under one point draws down the whole area), the size of the building footprint, and the radon entry characteristics. Ask that a post-mitigation test be done to verify effectiveness - if the cheap system works, great; if it doesn't achieve results below 4.0, the landlord needs to go back and do it right.

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I'm looking at apartments and one has a radon mitigation system already installed. Is that a good sign?

Generally yes - it means a prior owner or landlord took the issue seriously enough to install a system. But verify that the system is functioning and that post-mitigation test results confirm it's working. A system that's been installed but hasn't been serviced or tested in years may not be performing well. Ask for documentation.

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I'm moving into an apartment and the listing says "radon mitigated." What should I verify before signing?

Ask for: the original pre-mitigation test result, the installation documentation for the mitigation system, and the post-mitigation test result. Confirm the system is still running (the fan should be audible or a U-tube manometer should show suction). Consider running your own test once you're in. "Radon mitigated" is a starting point - the numbers tell the whole story.

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As a renter, should I care about radon if I'm only going to be in the apartment for a year?

One year of elevated radon exposure adds to lifetime cumulative risk. It's not zero - but it's also a smaller fraction of lifetime exposure than long-term residency. Even so, testing is cheap and easy, and knowing your levels is always better than not knowing. If levels are dramatically high - 8, 10 pCi/L or more - even a year is worth addressing.

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My apartment has 4.5 pCi/L and my landlord says they won't fix it "for that little." What do I say?

4.5 pCi/L is above the EPA action level - it's not a borderline case. You can explain that the EPA's recommendation to mitigate at 4.0 is based on lung cancer risk, not aesthetics, and that "a little above" is still in the actionable range. Document your request in writing. If the landlord refuses, your next step is your state health department or radon program.

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I'm a renter and I want to help my neighbor who's in a worse unit than mine. Can I share my monitor with them?

You can let them borrow your monitor - it just takes several weeks to get a meaningful reading for a new location. Alternatively, a short-term charcoal test is quick and inexpensive. Helping a neighbor get a test result is genuinely helpful, especially if you're in the same building and this might prompt a broader landlord response.

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I saw a radon mitigation ad that says they can reduce radon to zero. Is that accurate?

No - that's overclaiming. Radon mitigation can dramatically reduce levels and typically brings them well below the EPA action level, but achieving absolute zero is not realistic or necessary. The goal is getting below 4.0 pCi/L and as close to or below 2.0 as practical. Anyone claiming they'll eliminate radon entirely is making a promise the science doesn't support.

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I'm renting a space from a friend informally - no lease. Do I still have rights around radon?

Even informal rental arrangements create some landlord-tenant relationship under most states' laws. Without a written lease, your rights may be harder to enforce, but you're not without them. In practical terms, the conversation with a friend landlord should be relationship-focused rather than legal - explain the issue, share the test results, and approach it as something you're working through together.

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The radon in my rental has been consistently 3.7 for three months on my monitor. Should I try to push my landlord to fix it?

3.7 is just below the EPA action level, but the EPA explicitly says levels between 2.0 and 4.0 are worth considering mitigation because the risk is lower but real. You can certainly make the request - your landlord may be willing, especially if the cost is modest. If they decline at 3.7, you're not in clearly actionable territory legally in most places, but you can continue monitoring and revisit if levels trend up.

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I found a mitigation contractor myself and want my landlord to use them. Can I do that?

You can suggest a contractor. Your landlord may prefer to choose their own contractor, which is their right as the property owner. What matters most is that a qualified, licensed radon mitigation contractor does the work and that post-mitigation testing confirms results. Who the landlord calls is less important than whether it gets done right.

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I rent a room in a shared house and I live in the basement. My housemates on the upper floors don't care about radon. What can I do?

You're in the most exposed space - your concern is valid even if your housemates' concern is low. Your radon exposure is your issue to address regardless of what anyone else in the house thinks. Bring the test result to the landlord directly in your own name. You don't need consensus from your housemates to request a habitability fix for your own room.

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I'm staying with a friend in their basement for a few months while I save money. Should I worry about radon?

A few months is on the shorter end of meaningful exposure, but if the space has very high levels it's not nothing. It's worth picking up a short-term test - they're cheap - to know what you're dealing with. If the reading is dramatically high, you and your friend can decide together whether to address it or adjust your living arrangement.

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I'm renting a basement in-law suite attached to the main house. Is radon in my unit linked to radon in the main house?

In-law suites that share a foundation with the main house often have similar soil contact dynamics, but the radon levels in each space can differ based on air exchange, sealing, and pressure. The in-law suite at below-grade level may actually have higher levels than the main floor above. Test your space specifically.

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I'm a live-in caregiver staying in the basement of the person I care for. Should I be checking for radon?

Yes - you're spending significant time in that basement space, possibly more than the homeowner. Your health matters here too. Suggest to the homeowner that a test is worthwhile, and if they're open to it, run one together. If levels are elevated, both of you benefit from mitigation.

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I live in a basement unit in a building my employer owns as employee housing. Who do I contact about radon?

Your employer-landlord has the same habitability obligations as any other landlord. Put your concern in writing to whoever manages the employee housing - facilities management, HR, or your supervisor. Document the test results. If the employer-landlord is unresponsive, your state health department or radon program can provide guidance regardless of the employer relationship.

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My basement apartment is in a converted historic building. Does that affect radon?

Older historic buildings often have stone or brick foundations with more gaps and less sealing than modern poured concrete. They can have more radon entry points. Whether they actually have high radon depends on the local geology and soil conditions. The building's age and construction type are a reason to test, not a warranty of a problem.

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I'm renting a space above a commercial business and my unit is at street level. Is radon a concern?

Ground-level units above commercial spaces can have radon concerns if there's soil contact below the commercial slab and if air from that space migrates into your unit. It depends a lot on how the building is constructed. Test your specific unit at the floor level - that's the only way to know.

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I rent a basement apartment in a duplex. The upstairs owner-occupant says they've never had a problem. Does that mean I'm fine?

The upstairs owner is living several feet above the soil - their experience with radon is meaningless for your basement situation. Radon concentrates in the lowest levels. The fact that someone above you has never noticed an issue doesn't tell you anything about what you're breathing below grade. Test your unit.

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I'm a graduate student in university-provided housing in a basement unit. The university says they comply with all regulations. Does that mean radon is fine?

"Complying with all regulations" in most states doesn't specifically mean radon has been tested or mitigated - because radon regulations are limited or nonexistent in many states. Ask specifically whether your building and floor have been tested for radon, and request documentation of results. General regulatory compliance is not the same as radon testing.

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I'm renting a basement apartment in an area that has historically been used for mining. Should I be more concerned about radon?

Mining activity can disturb geology and in some cases is associated with elevated radon in surrounding areas. Your region's radon zone status and any local health department data on radon in former mining areas is worth looking into. But the most useful thing is still testing your actual unit - geology and history are context, not your answer.

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My basement apartment is in a building that was originally built as a commercial space and later converted to residential. Does that matter for radon?

It can. Commercial-to-residential conversions may have different foundation designs, slab thickness, and sealing compared to purpose-built residential. They may also have penetrations from prior commercial use. None of that tells you what the radon level is - but it's a reason to test rather than assume.

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My radon test says 4.1 pCi/L. Is that meaningfully different from 3.9?

From a health risk standpoint, 4.1 and 3.9 are essentially the same - the EPA's 4.0 threshold is a guidance value, not a sharp cliff where everything changes. The EPA recommends action at 4.0 or above and says to consider mitigation between 2.0 and 4.0. At 4.1, you're in action-recommended territory. At 3.9, you're just below it but still worth monitoring.

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My test came back at 8.3 pCi/L. What category is that?

8.3 pCi/L is more than twice the EPA's action level. The EPA's guidance is to act at 4.0 and above - at 8.3, this is a significant finding that warrants prompt mitigation, not a "we'll get to it eventually" response. Escalate to your landlord immediately in writing, and if they're slow to respond, contact your health department.

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My state's radon program says my county is Zone 1 (high radon potential). My test came back at 2.1. Should I trust the result?

Zone 1 means the county has higher radon potential on average - it doesn't mean every home in the county will have high radon. Geology varies at the neighborhood and block level. A result of 2.1 is below the action level, and if the test was conducted properly (closed-house conditions, correct placement), it's a valid result. Continue monitoring with a long-term approach if you want ongoing confidence.

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I did both a short-term and a long-term test. The short-term said 5.2 and the long-term said 3.6. Which do I use?

The long-term test is the more accurate representation of your typical exposure over time. It captures seasonal variation and accounts for the highs and lows that a short-term test might catch or miss depending on when it was run. Use the long-term result as your guide - though 3.6 is still in the range where the EPA says mitigation is worth considering.

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The lab report shows pCi/L. My monitor shows WL (working levels). Are those the same?

They're related but different units. Picocuries per liter (pCi/L) measures radon concentration in air. Working levels (WL) measure the potential alpha energy from radon decay products. For residential comparisons, pCi/L is the standard unit used by the EPA. One WL is approximately 200 pCi/L of radon. Most consumer monitors and test kits report pCi/L.

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My continuous monitor shows pBq/m³ instead of pCi/L. How do I convert it?

Divide the Becquerels per cubic meter value by 37 to get pCi/L. So 150 Bq/m³ is about 4.1 pCi/L. European monitors often use Bq/m³; US guidance uses pCi/L. The EPA's action level of 4.0 pCi/L is equivalent to roughly 148 Bq/m³.

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My charcoal test report shows a result with an asterisk and a note about QC. What does that mean?

An asterisk with a quality control note usually means something about the test conditions fell outside the ideal parameters - it could be the test ran too long, was exposed to some air flow, or had a chain-of-custody question. Read the note carefully. If the report says the result should not be relied upon, request a replacement kit and retest. If it's a minor QC flag with a still-valid result, the number is likely usable.

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I put my test on the windowsill by mistake. Do I need to redo it?

Yes. A windowsill is too close to an exterior wall and potentially exposed to drafts, which can significantly alter the result. Redo the test following EPA placement guidelines - at least 20 inches from exterior walls and windows, at breathing zone height, away from drafts and direct sunlight.

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My test was open for more than 96 hours because I forgot to mail it right away. Is the result still valid?

Check the test kit's instructions - most specify a maximum exposure period. If you exceeded the maximum significantly, the result may be less reliable, and the lab may flag it. Some labs will still process and report the result with a note about the extended exposure time. If there's a significant question, it's worth doing a retest.

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I got two test kits and ran them at the same time in the same room. The results were 4.1 and 3.5. Why are they different?

Duplicate tests run simultaneously typically show some variation - this is normal and expected. The difference is within the range of typical test-to-test variability for short-term charcoal tests. Average the two results: (4.1 + 3.5) / 2 = 3.8. That average is a more reliable estimate than either individual test.

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My monitor shows radon in "counts" rather than pCi/L. What does that mean?

Some simpler radon monitors report internal counts or arbitrary units rather than calibrated pCi/L values. If the device doesn't report in pCi/L, it may not be a calibrated radon measurement tool - it could be a novelty device rather than a real radon monitor. For accurate readings, look for devices that display pCi/L and have documented calibration methodology.

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How do I write a letter to my landlord about high radon?

Keep it factual and professional. Include: the test result and units (e.g., "my continuous monitor shows a 30-day average of 5.4 pCi/L"), the date you discovered it, a reference to the EPA's action level of 4.0 pCi/L, and a specific request ("I am requesting that radon mitigation be performed by a licensed radon professional within 30 days"). Send via email so you have a timestamp and record.

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My landlord keeps saying they'll "look into it" without actually doing anything. How do I keep pressure on them without being adversarial?

Follow up in writing on a regular cadence - every two weeks is reasonable. Keep the tone informational and neutral: "Checking back on my request from [date] regarding radon mitigation. Can you share your timeline?" The paper trail is what protects you. If they continue to stall past a reasonable timeframe, escalate to the health department - that's not adversarial, that's using the system appropriately.

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What should I do if my landlord says they've never heard of radon?

Take the opportunity to educate them briefly - explain it's an odorless gas from soil that's the second leading cause of lung cancer, that the EPA recommends fixing it above 4.0 pCi/L, and that it's very fixable with a standard system. Give them your test result in writing. Most landlords, once they understand what they're looking at, take it seriously. The ignorance is usually genuine, not malicious.

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My landlord said they'll fix the radon "if you pay for half of it." Is that reasonable?

No. The mitigation system is a structural improvement to their building. The tenant doesn't pay for structural modifications. You can frame it that way: "This is an improvement to the property that stays when I move - it's appropriate for the owner to cover the cost." If they insist, document the conversation and consult a tenant's rights organization.

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My property management company keeps routing me to a maintenance line that never calls back. How do I escalate?

Send an email - not just a phone call - to the property management company's general or corporate address, clearly stating the issue, your test result, and the date of your original report. Cc your direct property manager. A written communication to a corporate contact creates accountability that a maintenance voicemail doesn't. If the company ignores written communication on a health and habitability issue, that's when your health department complaint becomes the right next step.

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I asked my landlord to test and they sent someone who just walked around with a detector for 5 minutes and said "it's fine." Is that a real test?

No. A valid radon test requires either a charcoal canister left in place for 48-96 hours and analyzed by a lab, or a calibrated continuous monitor running for at least a week. Someone walking around with a handheld device for five minutes is not a recognized radon measurement method. Request documentation of a proper test - lab results from a licensed facility.

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My landlord says they fixed the radon by opening up some vents in the crawl space. Is that mitigation?

Crawl space ventilation can help with radon entry in some cases - it's actually a recognized mitigation technique for crawl spaces when done properly (passive vents to the exterior that create airflow). Whether it worked depends on the specific setup and the post-ventilation test results. Ask for documentation that radon was tested after the vents were opened and that levels came down to below 4.0. Without test results, "we opened some vents" isn't a verifiable answer.

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My landlord told me radon is "just naturally occurring so it's not their responsibility." What's wrong with that argument?

Lead paint, asbestos, and carbon monoxide are also naturally occurring or naturally derived - that doesn't exempt landlords from addressing them when they pose health risks. "Naturally occurring" is not a legal or ethical defense for maintaining a hazardous living environment. Landlords have habitability obligations regardless of whether the hazard has a natural origin.

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How specific should I be when writing to my landlord about radon?

As specific as possible. Include: the test method used (short-term charcoal, continuous monitor make/model), the exact reading (e.g., 5.7 pCi/L 30-day average), the placement of the device (bedroom, basement level), the dates the reading covers, and the EPA's guidance (4.0 pCi/L action level). Specificity makes your communication harder to dismiss and signals that you know what you're talking about.

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My landlord agreed to mitigate but wants to wait until spring when construction is easier. Is that reasonable?

Waiting a few weeks for better weather can be reasonable - radon mitigation involves drilling through a concrete slab and routing pipe to the exterior, and some contractors have seasonal scheduling. A few weeks is different from months. Get the specific target date in writing. More than 6-8 weeks of wait for a serious reading is not acceptable; push for urgency proportional to your exposure level.

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Is it possible for radon to be high in my unit but the unit next to me on the same floor to be low?

Yes, absolutely. Even units on the same floor and level can have different radon levels based on proximity to soil-contact areas, individual HVAC dynamics, the location of penetrations in the slab, and differences in interior air pressure. Neighboring units' test results are useful context but not a substitute for testing your own space.

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My landlord claims they fixed radon in the whole building. My unit still shows 4.9 on my monitor. Who do I believe?

Your monitor. Real-world air in your specific unit is the only thing that matters for your exposure. A building-wide mitigation system may have worked well in some units and less well in others depending on the sub-slab configuration. Show your landlord the continuous reading and ask the mitigation contractor to assess whether your unit's suction zone was properly addressed.

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Can I ask my landlord to add a radon monitor to the unit as a permanent fixture?

You can ask. Some landlords are willing to install a basic continuous monitor so they and tenants have ongoing visibility. This is increasingly common in newer and more professionally managed properties. It's a reasonable request, especially if you've had elevated levels in the past or the unit is below grade.

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I'm moving from a low-radon area to a high-radon area for a new job. Should I build radon awareness into my apartment search?

Yes. Ask prospective landlords for radon test results, and prioritize above-grade units if you have a choice. Plan to test within the first few weeks of occupancy. If you're moving to a Zone 1 EPA county, assume there's a higher probability of elevated levels and investigate accordingly.

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I bought a home radon test kit six months ago and never used it. Is it still good?

Short-term charcoal canister kits have a shelf life - typically around one to two years from the manufacturing date, depending on the product. Check the packaging for an expiration date. If it's within date, it should be fine. If you're not sure, the cost of a new kit is low enough that replacing it is the cautious choice.

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My radon monitor fell off the shelf and hit the floor. Do I need to recalibrate it?

Consumer monitors are generally designed to be reasonably durable. A short drop probably didn't affect calibration. Let it run for a few days after repositioning and compare to any historical baseline you have. If readings seem dramatically different from what you'd seen before, contact the manufacturer's support - some brands offer calibration services or replacement programs.

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I have an old Airthings Wave (original version). Is it still accurate?

Older Airthings models can drift over time without factory recalibration. Airthings has historically offered recalibration services for older units. Check the Airthings website or contact their support to see whether your model can be verified or recalibrated. As a general rule, consumer monitors more than 3-5 years old benefit from verification against a professional test.

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My cousin rents a basement and told me not to worry because "everyone in the neighborhood has lived here forever with no problems." Is that logic sound?

No. Radon doesn't cause symptoms - people live with elevated radon for decades and never know it's present. The absence of visible illness in neighbors doesn't mean radon isn't elevated. Lung cancer caused by radon develops over years and decades, and most people don't connect it to where they lived twenty years ago. Your cousin's logic is understandable but not scientifically sound.

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The apartment I'm looking at has a radon fan installed but the pipe is venting into the attached garage rather than the exterior. Is that okay?

No. Radon mitigation systems must vent to the exterior of the building - outdoors where the radon disperses into open air. Venting into an attached garage recirculates radon into a space that's often poorly ventilated and connects to the living area. That's an improper installation. The pipe needs to be extended to vent outside.

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My Airthings app says my air quality is "good" despite showing 4.8 pCi/L for radon. How does the app define "good"?

The Airthings app's color-coded quality indicators are based on their own thresholds, which may differ from EPA guidance. Don't rely on the color coding for radon - look at the actual pCi/L number. 4.8 pCi/L is above the EPA action level regardless of what color the app shows.

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I rent an apartment and want to know if my building was ever tested for radon in a government program. How do I find that out?

Some states maintain databases of radon test results submitted through licensed testers or state programs. Contact your state radon program and ask whether they have historical test records for your address. Not all states have such databases, and not all tests are submitted to state systems, so the absence of a record doesn't mean the building hasn't been tested.

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I'm moving out soon and the landlord wants to test for radon before I leave. Should I cooperate?

Yes - cooperating is the right thing to do, and a test before you leave gives you a documented result from your tenancy period. Make sure you're given a copy of the results. If the test was your landlord's idea and not required under your lease, there's generally no obligation to provide access, but cooperating is reasonable and may benefit future tenants.

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I'm a renter who does a lot of working from home in my basement office. Does that change how seriously I should take radon?

Significantly, yes. Working from home in the basement means you could be spending 8 or more hours a day in the highest-radon zone of the building. Your cumulative exposure is much higher than someone who only sleeps in the basement. If your basement home office has elevated radon, that's a real priority to address.

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My landlord asked me to not "make it a big deal" about the radon to other tenants. Should I comply?

No. You have no obligation to keep other tenants in the dark about a health hazard. In fact, warning neighbors who may be in similar situations is a reasonable and ethical thing to do. A landlord asking you to stay quiet about a habitability issue is not a request you're required to honor.

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My Airthings just updated its firmware. Could that change my radon readings?

Firmware updates can sometimes adjust measurement algorithms. After a firmware update, give the device a week or two to re-establish its baseline before drawing conclusions from the new readings. If you see a dramatic unexplained change right after an update, check the Airthings community forums - other users will often note if an update affected readings.

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I'm renting in a very old brick row house. The basement is unfinished stone. Is that a high-radon situation?

Unfinished stone foundations are highly permeable to radon - there's essentially no barrier between the soil and your basement air. Old row houses with stone foundations and unfinished basements are commonly high-radon environments in many regions. If your living space is at or below grade in such a building, testing is a priority.

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I found out my basement apartment had a previous tenant who complained about radon and nothing was done. What should I do with that information?

Use it to push your landlord harder and faster. The fact that a prior tenant flagged the issue and it wasn't addressed is documented history of the landlord's inaction. If you have that information in any written form - a note from the prior tenant, old maintenance records - keep it. It strengthens any formal complaint you might need to file.

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My landlord is selling the building. Does that change my radon situation as a tenant?

That part should be handled through the transaction, lease, or property-management process, not as contract or lease advice from a mitigation contractor. The radon side is more straightforward: confirm the result if appropriate, understand whether an existing system works, and decide whether mitigation, passive activation, repair, or follow-up testing is needed for the specific property. A buyer, seller, tenant, or landlord should talk with the appropriate real estate, legal, property-management, or housing contact about deadlines, credits, contract rights, or lease obligations. Bill can help explain what the mitigation work would involve and what property details should be checked.

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I'm renting from a real estate investor who owns dozens of properties. Will they take my radon concern seriously?

Professional investors with large portfolios are often more organized about habitability issues than individual small landlords, because they have legal and management processes in place. Escalate through their proper management channel in writing. Large landlords also have more liability exposure, which can actually make them more responsive when a formal complaint is filed.

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What's the simplest possible thing I can do today if I'm worried about radon in my rental?

Buy a short-term charcoal radon test at your nearest hardware store, place it in the lowest room you spend time in, follow the instructions, and mail it in at the end of the test period. You'll have results in about two weeks. That's it - everything else can follow from knowing your number.

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I rent a finished basement apartment. Can radon still get through the drywall and flooring?

Radon doesn't come through drywall - it enters through the concrete floor and foundation walls, and through penetrations like pipe chases, utility holes, and the floor-to-wall joint. Finished walls and flooring add some resistance but don't seal off these pathways. The source of entry is below and behind the finished surfaces, not through them.

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My landlord said the radon test was done "by a professional" but couldn't give me the lab report. Should I push for the actual paperwork?

Yes. A professional radon test generates a written lab report with the address, date, result, lab ID, and often the tester's certification number. If your landlord can't produce that document, the test either wasn't done or the results weren't favorable. Ask specifically for the lab report - not a verbal summary.

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My basement apartment has a French drain around the interior perimeter. Does that affect radon?

Interior French drains collect water from the base of foundation walls and route it to a sump. They can also create a pathway for soil gas, including radon, to enter along the wall-floor joint. A French drain with an open channel is a more direct radon entry route than a fully sealed slab. In a mitigation design, the French drain and sump system are typically addressed as part of the overall sub-slab pressure approach.

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I'm renting and just had a baby. Does that change how urgently I should deal with radon above 4.0?

A new baby doesn't change the physics of radon, but it's completely understandable to want to minimize all avoidable health risks at home. Radon's danger is cumulative over years, not acute - your infant is not in immediate danger from days or weeks of exposure. Even so, pursuing mitigation promptly is the right call when you have a young child and elevated radon. It reduces long-term exposure for everyone in the home.

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I've tested my rental and everything looks good. Is there anything I should keep in mind going forward?

Radon levels can change over time - as buildings settle, soil conditions shift, or mitigation systems (if any) age. Testing every two years, or after any major renovation or significant change to the building, is a reasonable habit. A continuous monitor running in the background gives you passive ongoing awareness without needing to think about it. Low levels now are reassuring; periodic verification keeps them that way.

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Related Help

Buying or selling with radonHelp for landlordsContact Bill

Questions are fine too. Call or text Bill, or send your address and contact info, and he will take it from there.

Reviewed by Bill Dahlstrom, Illinois radon mitigation license RNM2018212.