What Is Radon Testing in Apartments?

On this page (8 sections)

1. What is radon testing in apartments checking?
2. Where should you put a radon detector in an apartment?
3. How do shared buildings affect apartment radon results?
4. How do you use an apartment radon test kit?
5. What should renters ask the landlord or property manager?
6. What if an apartment radon result is high?
7. How often should an apartment be tested?
8. What is the practical way to test radon in an apartment?

Radon testing in apartments measures the radon gas level in the air inside a specific unit using a short-term kit or a continuous monitor. Put the detector in a regularly occupied room on the lowest level of your apartment and follow its instructions; a building-wide result may not represent your unit.

Radon comes from the ground and can enter buildings through openings in foundations, utility routes, and other gaps. In a shared building, the level can differ from apartment to apartment because units occupy different floors and have different air paths.

What is radon testing in apartments checking?

Apartment radon testing checks the concentration of radon in the air where you live during a stated test period. It doesn't measure every unit or establish that the whole building has the same level.

A test may use a passive collection device sent to a lab, or an electronic monitor that displays readings. Short-term tests give a snapshot over a set period; longer testing can show more about typical conditions over time.

Testing a single unit is still useful. It helps you decide whether to repeat the test, ask management for help, or seek guidance from a qualified radon professional.

For an overview of the process and common test types, read What Is Radon Testing? A Beginner’s Guide.

If you want a straightforward walkthrough of kit setup, see How to Test for Radon: The Simple Answer.

Where should you put a radon detector in an apartment?

Put a detector in a room you use regularly on the lowest level of your apartment, and follow the device's instructions for exact placement. If your unit is on an upper floor, ask the building manager whether a lower occupied area or additional units should also be tested.

Choose a room such as a living room, bedroom, or home office. Keep the detector away from drafts, direct sunlight, high humidity, exterior walls, and spots where people might move or cover it.

Don't put it in a bathroom, kitchen, laundry room, closet, or other space where air conditions or use may not match normal living areas. Avoid placing it next to windows, doors, vents, or fans unless the test instructions say otherwise.

Does apartment floor level change the test location?

The lowest lived-in level is generally the most useful starting point because radon can enter from the ground. In a high-rise, that may mean a first-floor apartment rather than a basement, but building design and local testing guidance can affect the best location.

If you rent above ground level, test the space where you spend time and ask management about the building's lower levels. For renter-specific steps, see testing radon as a tenant.

A reading from a basement, lobby, or another apartment can add context, but it can't replace a test in your unit.

How do shared buildings affect apartment radon results?

Shared buildings can have different radon readings in different apartments, even when units are close together. Floor, connection to the ground, ventilation, pressure differences, and building openings can all affect how radon moves.

A reading from a neighbor's unit doesn't prove your apartment has the same level. Even adjacent apartments may differ, so test your own occupied space when you need to know its result.

Building management can help coordinate testing across units and common areas. For resident communication, see a radon test notice.

This can be useful when a lower-level unit has a high result, when several residents have concerns, or when a professional needs to understand how air moves through the building.

If the building is new or recently renovated, see how to test for radon in new construction. Construction age alone doesn't tell you whether an apartment has radon.

How do you use an apartment radon test kit?

Use the kit exactly as its instructions direct, including the test period, placement, registration, sealing, and return steps. The test method and the lab's instructions determine how to collect a useful sample.

Before starting, check whether the kit is intended for use in your location and whether lab fees or return postage are included. Keep the detector undisturbed during the test and note the start and end times if the instructions ask you to.

The First Alert Radon Gas Test Kit includes test materials and lab fees, excluding New Jersey state fees, and results are emailed within 72 hours of lab receipt. It is recommended for use only within the United States.

The PRO-LAB Radon Test Kit for Home uses a 48-hour collection period and includes lab analysis, with email or text updates. Its instructions describe placement in a frequently occupied room, which can suit an apartment test when the kit's directions match your situation.

The Leaping Lynx Radon Test Kit for Home is a 48-hour short-term test with lab analysis included; postage is required to return the detector. Its instructions call for placement on the lowest livable level, a practical fit for an apartment on the building's ground floor.

For a closer look at timing, read How Long Is Short Term Radon Testing? A Fuller Explanation.

What should renters ask the landlord or property manager?

Ask management whether the building has a testing policy and how it handles follow-up. Share your test dates, the room tested, and the result so they can interpret it in the context of the building.

Useful questions include:

• Has the building been tested, and which units or common areas were included?
• Was a qualified radon professional involved?
• Does management have a process for confirming a raised result?
• Can a professional assess lower floors or other units if needed?
• Who will arrange and pay for any building follow-up?

Keep a copy of the result and the test instructions. If management coordinates a wider test, ask how units will be selected and how residents will receive the findings.

What if an apartment radon result is high?

If a result is high, check the test instructions and discuss follow-up with building management. A short-term result is a reason to seek a properly conducted follow-up, not to assume every apartment in the building has the same level.

Make sure the device was placed correctly and left undisturbed for the required period. If you suspect a setup problem, repeat the test according to the kit directions or ask a qualified professional what test is appropriate.

A radon professional can help assess the unit and building, explain additional testing, and recommend ways to reduce radon if needed. Ask management to document the next steps and timing.

For more context on when to test, read when radon testing is necessary.

Radon is often described as a heavy gas, but that fact alone doesn't predict a specific apartment's reading; see Is Radon a Heavy Gas? A Wider Look at the Facts.

How often should an apartment be tested?

Test when you need information about the air in your unit, such as after moving in or when building conditions change. Consider another test after major renovations, changes to heating or ventilation, or work that affects floors or openings near the ground.

For a broader indoor air plan, see mold and radon testing.

Follow local public health guidance and any building policy for timing. A previous result from another tenant may be useful background, but it doesn't replace a current test in your apartment.

What is the practical way to test radon in an apartment?

For a basic apartment check, test the lowest regularly occupied level in your own unit and follow the kit instructions. If your apartment is above ground level, ask management whether lower areas or other units need testing too.

Choose a mail-in kit if you want a lab result, or an electronic monitor if you want readings over time. The First Alert kit includes lab fees except for New Jersey state fees; PRO-LAB provides a 48-hour collection with lab analysis included; Leaping Lynx also uses a 48-hour period, with return postage required.

If a result is high, repeat or confirm the test as appropriate and involve the property manager. A building professional can help determine whether the issue is limited to one unit or needs a broader response.

Frequently asked questions

Can you test for radon in an apartment?

Yes. A renter can test the air inside an apartment with a radon kit or continuous monitor.

Follow the device instructions for placement and timing, and ask the landlord or property manager about building testing, especially if the unit is above shared lower floors or the result calls for more testing.

Where should a radon detector go in an apartment?

Place the detector in a room you use regularly on the lowest level of your apartment, following the test kit's exact placement directions. Keep it away from drafts, direct sunlight, high humidity, exterior walls, and places where it could be disturbed.

Do apartments need radon testing?

Testing is the way to know whether radon is present at a high level in a particular apartment. Radon can vary between units and floors, so a neighbor's result may not represent your space.

Consider testing after moving in, renovations, or a change in the building.

What should you do if an apartment radon test is high?

Check that the test was set up and returned as directed, then share the result with the landlord or property manager and ask about a follow-up test. A qualified radon professional can assess the building and recommend next steps; avoid treating one short-term result as a final diagnosis of the whole property.