Radon Testing in Michigan: Complete Homeowner Guide (2026)
Radon Testing in Michigan: What You Need to Know
Michigan is classified as EPA Zone 1, indicating high radon potential. Michigan has moderate to high radon potential, with the Lower Peninsula showing generally higher levels than the Upper Peninsula. Grand Rapids, Lansing, Ann Arbor, and the Detroit suburbs consistently show elevated radon. Glacial deposits and shale bedrock contribute to the state's radon risk.
Radon is a colorless, odorless radioactive gas that seeps into homes through cracks and gaps in the foundation. It is the leading cause of lung cancer among non-smokers, responsible for approximately 21,000 deaths per year in the United States. The only way to know if your home has elevated radon is to test.
Types of Radon Tests
Short-Term Testing (2 to 7 days)
Short-term tests provide a quick snapshot of radon levels. They are used for initial screening and real estate transactions. Professional short-term testing in Michigan costs $100 to $275. DIY charcoal canister kits cost $15 to $40.
Long-Term Testing (90 days to 1 year)
Long-term tests give a more accurate picture of your home's average radon level across seasons. Alpha-track detectors are the most common long-term device. These cost $20 to $50 for DIY kits. Because radon levels fluctuate with weather, season, and home ventilation, the EPA considers long-term results more reliable for making mitigation decisions.
Continuous Radon Monitors (CRM)
Professional radon testers use continuous radon monitors that record levels every hour. These devices provide the most detailed data and are tamper-resistant, making them the standard for real estate transactions. CRM testing typically costs $100 to $275 in Michigan.
When to Test for Radon
- Buying a home - Always test before closing. Most home inspectors offer radon testing as an add-on service. Michigan law requires sellers to disclose known radon test results.
- Selling a home - Test before listing to avoid surprises. If levels are high, you can install mitigation proactively.
- Never tested - If you have lived in your home for years without testing, do it now. The test takes less than a week.
- After renovations - Major work on your foundation, HVAC system, or insulation can change radon entry patterns.
- Re-testing - The EPA recommends re-testing every 2 years, even if previous results were low.
How to Read Your Results
| Radon Level (pCi/L) | Risk | Recommended Action |
|---|---|---|
| Below 2 | Low | No action needed. Re-test in 2 years. |
| 2 to 4 | Moderate | Consider mitigation. Re-test to confirm. |
| 4 to 8 | High | Install mitigation system. EPA action level is 4 pCi/L. |
| Above 8 | Very High | Take action promptly. Equivalent to smoking half a pack of cigarettes per day. |
The EPA action level is 4 pCi/L, but there is no truly safe level of radon. The WHO recommends action at 2.7 pCi/L. If your test shows levels between 2 and 4 pCi/L, a follow-up long-term test is a good idea.
DIY vs. Professional Testing
Both approaches can give accurate results, but professional testing is preferred for real estate transactions. A certified radon tester uses calibrated equipment, follows strict placement protocols, and provides results that are accepted by lenders and real estate agents.
If you are testing for your own information, a DIY kit from a hardware store is a reasonable starting point. Place the detector in the lowest livable level of your home, keep windows and doors closed for 12 hours before and during the test, and follow the kit instructions exactly.
Find a Certified Radon Tester in Michigan
Browse NRPP-certified radon professionals in Michigan in our directory. Look for professionals with the RT (Residential Testing) or ASP (Analytical Services) certification.
Frequently Asked Questions
How much does a radon test cost in Michigan?
Professional radon testing in Michigan costs $100 to $275. DIY radon test kits are available for $15 to $40 at hardware stores.
Do I need a radon test in Michigan?
The EPA recommends testing all homes for radon regardless of location. Michigan is in EPA Zone 1, which means high radon potential. Michigan also requires radon disclosure during home sales.
How long does a radon test take?
Short-term radon tests take 2 to 7 days. Long-term tests run for 90 days to 1 year and give a more accurate picture of average radon levels in your home.
When should I test for radon?
Test when buying or selling a home, after major renovations, if you have never tested, or if your last test was more than 2 years ago. Winter testing tends to show the highest levels because homes are sealed tighter.
What radon level is dangerous?
The EPA recommends taking action at 4 pCi/L or above. The WHO recommends action at 2.7 pCi/L. There is no safe level of radon exposure, but levels below 2 pCi/L are difficult to reduce further.