Best Air Purifier for Radon-Affected Homes 2026: Mitigation + Filtration Guide

Do Air Purifiers Remove Radon?

No, not the gas itself. The EPA describes radon, chemical symbol Rn, as an odorless, colorless, radioactive gas. The federal health agency ATSDR calls it a noble gas. A HEPA filter is built to trap particles. The EPA says a HEPA filter can in theory remove at least 99.97 percent of airborne particles 0.3 microns in size. That rating is about particles, not gases.

Activated carbon is the filter type used for gases. The EPA says activated carbon filters can be effective when the filter holds a large amount of carbon. It also says there is no widely used rating system for how well portable air cleaners remove gases. None of that makes a purifier a radon fix. National Radon Program Services at Kansas State University says HEPA air filters will not affect radon levels.

What about the particles radon leaves behind? Radon decays into short-lived radioactive particles called radon progeny. The EPA says some of them attach to dust particles, and a HEPA filter traps dust. But the EPA does not recommend air cleaning to reduce the health risks from radon and its progeny. It says a limited number of studies have looked at air cleaners and radon progeny, and the amount of risk reduction they found was inconsistent.

Bottom line: if your test reads 4.0 pCi/L or higher, get a mitigation system. After that, a purifier is for dust, smoke, and other particles in the rooms where you spend the most time. It will not change your radon number.

The 3-Step Radon Workflow

Skip steps 1 and 2 and an air purifier does nothing for radon. The EPA says to test, then fix. A purifier comes last.

1. 1

   Test first

   Use a short-term test kit or a continuous radon monitor. The EPA says a short-term test stays in your home for 2 to 90 days, depending on the device. Test in the lowest lived-in level of the home. If your reading is 4.0 pCi/L or higher, the EPA says to take a follow-up test to be sure, then fix your home. If it is between 2.0 and 4.0 pCi/L, the EPA recommends that you consider fixing your home. Even if your result is below 4.0 pCi/L, the EPA says you may want to test again sometime in the future.

   See our reviews of the best radon detectors and continuous monitors for testing equipment picks.

2. 2

   Mitigate

   Active soil depressurization is the method the EPA calls the most effective. A vent pipe and a fan pull radon from beneath the house and vent it to the air above the home before it enters your living space. The EPA says most homes can be fixed for about the same cost as other common home repairs. National Radon Program Services at Kansas State University puts the national average at $1,200, with $800 to $1,500 common.

   See our full radon mitigation cost guide for what changes the price, plus how to vet an NRPP-certified contractor.

3. 3

   Filter

   Once the mitigation system is in and a follow-up test shows your radon has dropped below 4.0 pCi/L, you can add an air purifier in the rooms where you spend the most time. The purifier is for dust, smoke, and other particles. The EPA says portable air cleaners can reduce indoor air pollution but cannot remove all pollutants from the air. This is the polish step, not the fix.

5 Air Purifier Picks for a Radon-Mitigated Home

These are pair-with-mitigation picks, not replacements for mitigation. None of them will lower your radon gas reading. They are here for the dust and smoke particles in a basement, alongside an active soil depressurization system.

The figures in this table are each maker's own published numbers, and IQAir publishes no AHAM CADR for the HealthPro Plus.

What Air Purifiers Actually Do in a Radon-Affected Home

Here is what a purifier can and cannot do. None of it is removing the radon gas.

How to Size a Purifier for a Basement

CADR matters more than brand. The EPA says the higher the CADR, the more particles the air cleaner can filter and the larger the area it can serve. Most packaging tells you the largest room the unit should be used in. Here are the makers' own room sizes for three of the picks above.

Placement in a Mitigated Basement

The mitigation system is doing one job (pulling soil gas from under the house and venting it outside). The air purifier is doing a different job (passing room air through a filter). The purifier never replaces the radon system.

• Put the purifier in the rooms where you spend most of your time. That is the advice from the California Air Resources Board (CARB).
• CARB says to place the unit away from doors, windows, and foot traffic, but not next to walls or corners, so air can reach it easily.
• Replace the filter on the manufacturer schedule.
• Do not use ozone-generating air cleaners in a mitigated basement. The EPA calls ozone a lung irritant. CARB-certified units only.
• Never turn the radon fan off. The EPA says it must run continuously for the system to work correctly.

What Does Not Help (And What to Skip)

A few products that get marketed for radon and do not actually do anything useful for the gas itself.

• Standalone activated carbon air purifiers marketed as “radon removers.” The EPA does not recommend air cleaning to reduce the health risks from radon. Save the money for the mitigation install.
• Ozone generators and most ionizers. The EPA calls ozone a lung irritant. The California Air Resources Board (CARB) maintains a list of certified air cleaners, and electronic units on it must meet an ozone limit of 0.050 parts per million. Pick from that list or skip the category.
• UV-C “air sanitizers” alone. A UV lamp is not a filter. It does nothing for radon gas.
• “HEPA + ionizer” combo units. The HEPA stage is fine. The EPA says ion generators and some other electronic air cleaners produce ozone. Disable the ionizer and run HEPA-only mode if your unit allows it.
• Air purifiers in the basement when the rest of the house is unmitigated. The World Health Organization says radon levels are usually higher in basements and rooms in contact with the ground, but that considerable radon can also be found above the ground floor. A purifier does not lower radon on any floor.

Common Questions

References and Primary Sources

• US EPA, What is EPA's Action Level for Radon and What Does it Mean?, read 2026-10-05. Fix at 4 pCi/L or more, consider fixing between 2 and 4 pCi/L, average indoor level about 1.3 pCi/L, average outdoor level 0.4 pCi/L.
• US EPA, A Citizen's Guide to Radon (PDF), read 2026-10-05. Short-term and long-term tests, where to place a test kit, and the testing steps.
• US EPA, Consumer's Guide to Radon Reduction (PDF), read 2026-10-05. Soil suction methods, the 48-hour minimum test, and running the fan continuously.
• US EPA, Residential Air Cleaners: A Technical Summary (3rd edition, PDF), read 2026-10-05. EPA does not recommend air cleaning to reduce the health risks from radon and radon progeny. Studies found inconsistent risk reduction. Active soil depressurization is the most effective radon control technique.
• US EPA, Guide to Air Cleaners in the Home, read 2026-10-05. CADR, activated carbon filters, and the lack of a rating system for gases.
• US EPA, What is a HEPA filter?, read 2026-10-05. At least 99.97 percent of airborne particles 0.3 microns in size.
• US EPA, What are ionizers and other ozone generating air cleaners?, read 2026-10-05. Ozone is a lung irritant.
• US EPA, Does the 2009 WHO recommendation affect the EPA action level?, read 2026-10-05. The WHO reference level of 100 Bq/m3 is 2.7 pCi/L.
• US EPA, Radionuclide Basics: Radon, and ATSDR, ToxFAQs for Radon, read 2026-10-05. Radon is a radioactive noble gas. Its progeny have short half-lives.
• World Health Organization, Radon fact sheet, read 2026-10-05. National reference level of 100 Bq/m3, and where radon levels are usually higher in a building.
• National Radon Program Services (Kansas State University), Reducing Radon in Your Home, read 2026-10-05. HEPA air filtration systems will not affect radon levels. National average mitigation cost of $1,200, with $800 to $1,500 common.
• National Radon Proficiency Program (NRPP), read 2026-10-05. Certification program for radon professionals.
• California Air Resources Board (CARB), List of CARB-Certified Air Cleaning Devices and Air Cleaners and Ozone Generating Products, read 2026-10-05. Ozone limit of 0.050 parts per million for electronic air cleaners, and where to place an air cleaner.