Looking for your state's specific rules? Use the Action Level Advisor or browse state guides for permit and contractor requirements in your area.
Overview
This guide covers everything homeowners need to know about radon home sale disclosure. Whether you've just received a high test result, are evaluating whether to hire a contractor, or want to understand the technical process in detail, you'll find clear, actionable information here.
Key Points
- The EPA action level for radon is 4 pCi/L — at or above this level, mitigation is recommended.
- Always use NRPP or NRSB certified contractors, regardless of whether your state requires licensing.
- A post-mitigation test is required after any installation — it's the only way to confirm the system is working.
- Permit requirements vary by state and municipality. Most states do not require a statewide building permit, but electrical permits for the fan circuit are common.
Step-by-Step Process
- Test your home using a certified radon test kit. Place at the lowest livable level under closed-house conditions for at least 48 hours.
- Interpret your result. Use the test results guide or Action Level Advisor to understand what your pCi/L means.
- Check your state's requirements for contractor certification and permits using the permit guide or your state page.
- Hire a certified contractor. Get 2–3 quotes from NRPP or NRSB certified professionals. Review the contractor hiring guide for questions to ask.
- Post-mitigation test. After 24–48 hours, run a new radon test to confirm the system has reduced levels to below 4 pCi/L.
Free Homeowner Checklist
Download the one-page checklist covering every step from test results to post-mitigation sign-off.
Download Free PDFRelated Resources
Reading Test Results
What your pCi/L number means.
Permit Requirements
State-by-state permit guide.
Hiring a Contractor
Verification and questions to ask.
Disclaimer: This page is for general informational purposes only. Always consult a certified radon professional for guidance specific to your home and situation.