How to Test Your Home for Radon
Testing is the only way to know the radon level in your home. The process is simple, inexpensive, and can be done without professional help.
Short-Term Testing (2–7 days)
The quickest way to screen for radon. Charcoal canister or electret ion chamber devices are placed in the lowest livable level of your home for 2 to 7 days, then mailed to a lab for analysis.
- Cost: $15–$30 for a mail-in kit
- Available at hardware stores and online
- Keep windows and doors closed as much as possible during the test
- Place the test device in the lowest level of your home that you use regularly
Long-Term Testing (90+ days)
Provides a more accurate picture of your home's year-round average radon level, since radon levels fluctuate with seasons, weather, and ventilation patterns.
- Alpha track detectors or electret ion chambers
- Cost: $20–$40
- Best for confirming short-term results or getting a baseline
Professional Testing
Certified radon measurement professionals use continuous radon monitors (CRMs) that provide hour-by-hour readings over 48+ hours. This is often required for real estate transactions.
- Cost: $125–$250
- Results available within days
- Tamper-resistant for real estate purposes
- Find certified testers through your state radon program
Understanding Your Results
Low risk. No action needed, but consider retesting every few years since levels can change.
Moderate. The EPA recommends considering mitigation. Follow up with a long-term test to confirm.
Above EPA action level. Take steps to reduce radon. Contact a certified radon mitigation professional.
Significantly elevated. Prioritize mitigation. Consider a short-term retest to confirm, then mitigate promptly.
Radon Mitigation
If your home has elevated radon, a mitigation system can reduce levels by up to 99%. The most common method is sub-slab depressurization — a pipe and fan system that draws radon from beneath the foundation and vents it above the roofline.
- Typical cost: $800–$2,500 for installation
- Annual operating cost: $50–$100 (fan electricity)
- Most systems reduce radon to below 2 pCi/L
- Professional installation usually takes less than a day