A useful radon report starts before the measuring device arrives. Preparation helps the measurement reflect the conditions the test was designed to assess. This checklist is for homeowners planning an indoor-air radon test, including people preparing to buy or sell a home.
Radon is an invisible, odorless radioactive gas. It can accumulate in buildings, and long-term exposure increases lung cancer risk. Smell, a normal home inspection, and the age of a house cannot tell you its radon concentration. [2] If you are new to the subject, start with our explanation of radon and how it enters a home.
Which radon test should you choose?
Short-term tests measure for 2–90 days; long-term tests run for more than 90 days. A longer test generally gives a better picture of exposure across changing conditions. For a home purchase or sale, use a qualified tester and confirm the transaction’s requirements before scheduling. [3]
| Your situation | What to discuss |
|---|---|
| You want an initial measurement | A suitable short-term test and a plan for any follow-up. |
| You want a longer-term picture | A test lasting more than 90 days, when the initial result and circumstances allow. |
| You have a contract deadline | A qualified measurement professional, reporting time, access, and required protocol. |
| A system was recently installed | A post-mitigation test scheduled with the installer and, preferably, independent verification. |
Share your deadline when booking, rather than assuming a “48-hour test” means the final report will arrive exactly two days later. Device setup, retrieval, laboratory processing, and report delivery are separate parts of the appointment.
What should you do before a radon test?
- Get the instructions in writing. Ask about the start and finish time, required house conditions, device location, and who to contact if something changes.
- Tell everyone who uses the home. Include household members, tenants, agents, cleaners, and contractors. Put the testing dates on a shared calendar.
- Prepare for closed-house conditions. For a 2–4 day test, EPA’s checklist calls for at least 12 hours beforehand and the full test period. Normal brief entry and exit are allowed. [1]
- Keep access clear. Give the tester room to select a suitable location and leave the device there. Keep children and pets from handling it.
- Describe the home honestly. Mention a basement, crawlspace, addition, recent renovation, existing radon system, or planned lower-level bedroom or office.
For example, if a test begins at 9 a.m. Tuesday and requires a 12-hour preparation period, closed-house conditions need to begin by 9 p.m. Monday. That is a scheduling example; your actual test must follow its own instructions.
Where should the device go?
Placement depends on the test’s purpose and the applicable protocol. A room used regularly on the lowest appropriate level is generally relevant; kitchens, bathrooms, drafts, heat, and humidity can make locations unsuitable. Let the professional choose the location, or follow your kit’s specific placement directions. Do not move the device to a more convenient shelf after setup. [4]
What can you do during the test?
You can usually continue normal household activities while respecting the test conditions. Operate heating and cooling normally as directed; avoid deliberately bringing extra outdoor air into the home. Leave an existing active radon system operating. EPA’s testing checklist explains these conditions in more detail. [1]
If a window is left open, a device is knocked over, or an unexpected event occurs, record what happened and tell the tester. Do not conceal the event or try to compensate by changing conditions later. The tester can determine whether the measurement remains usable or needs repeating.
What happens when testing finishes?
For a kit, record the required information and return it promptly according to the laboratory instructions. Keep the complete report, including the test dates, location, method, and reported average. [4] Read our guide to interpreting radon test results before deciding what the number means for your home.
Make a simple home record: report, device instructions, notes about unusual conditions, and any follow-up appointment. This makes future comparisons much more useful than an isolated number saved in a text message.
Radon test preparation FAQs
Can I open a door during a radon test?
Normal entry and exit are allowed under closed-house conditions. Keeping an exterior door propped open or opening windows is different. Follow the written instructions for your measurement. [1]
Can I stay in the house?
A radon test does not require an empty home. Plan normal access around the written testing instructions and make sure every occupant knows not to disturb the device.
Does every short-term test take 48 hours?
No. Short-term methods span 2–90 days, and some devices require longer than 48 hours. Use the specified duration; ending a test early can undermine the result. [3]
Should I test if my neighbor’s result was low?
Yes. Another property’s result does not measure your home. Construction and ground conditions differ, so arrange a measurement for the property you actually occupy. [4]
Ready to schedule?
Explore Radon Eraser’s testing service and our service locations. When you contact us, have your property location, foundation type, and timeline ready so the next step is clear.
Sources and further reading
- EPA: Home Buyer’s and Seller’s Guide to Radon — testing checklist and house conditions.
- CDC: Radon and Your Health — exposure and health effects.
- CDC: Testing Your Home for Radon — test types and choosing a tester.
- EPA: A Citizen’s Guide to Radon — placement, testing, and follow-up.
This guide explains general U.S. homeowner guidance. Your device instructions and qualified tester’s applicable protocol govern the measurement.