Before buying or selling
A documented test can support due diligence, negotiation, and a clear record for the transaction.
Professional radon testing services
Radon Testing in Billings, MT
Get a useful radon measurement, understand the result, and move forward with a clear testing or mitigation plan.
Professional testing starts with the decision you need to make
Radon levels can change over time and with weather, ventilation, occupancy, and building conditions. A useful test starts with the right device, location, duration, and controls for the decision you need to make.
We match the test approach to the property and purpose. Real-estate measurements must fit contract deadlines and current standards, while homeowner testing can use a longer measurement when time allows.
When professional testing may be useful
After an elevated screening result
A qualified professional can help determine whether a follow-up test is appropriate and which protocol fits the decision.
After a mitigation system is installed
Post-mitigation testing verifies the initial result. Periodic retesting checks whether levels remain reduced.
After meaningful home changes
Retest after foundation work, additions, major air-sealing changes, or a move into a previously unused lower level.
What a careful test process covers
Each action has a clear output. Keep the report and system decisions in writing.
Define the decision
Clarify whether the test supports a home purchase, a mitigation decision, a post-installation check, or routine monitoring.
Choose the method
Select a short-term, long-term, or continuous-monitor approach that matches the timeline and current standards.
Place the device correctly
Use the lowest suitable occupied level and avoid locations where drafts, humidity, heat, or interference could bias the result.
Maintain test conditions
Follow device instructions and the applicable closed-building conditions. Record anything that could affect interpretation.
Review the report
Confirm start and stop times, location, method, result, units, quality controls, and the professional responsible for the test.
What can affect the test plan
Deadline
Transaction dates can narrow the available test methods.
Lowest occupiable level
The intended use of a basement or lower room affects placement.
Foundation layout
Separate foundation zones or large footprints may require more than one measurement location.
Prior results
The value, method, date, and conditions of earlier tests help determine the next step.
Recent changes
Renovations, HVAC changes, windows, additions, and foundation work can justify retesting.
Potential interference
A professional plan should address device security and unusual building activity.
Information to prepare
- The address or ZIP code and the lowest level that could be occupied
- Any prior test report, including device, dates, location, and result
- The decision deadline and whether a real-estate contract is involved
- Known additions, crawlspaces, sump pits, foundation changes, or active mitigation equipment
- Access instructions and any unusual occupancy or ventilation conditions
After the result
- Keep the complete report, not only a screenshot of the final number.
- Use EPA guidance and the professional’s protocol-based recommendation to choose the next test or mitigation step.
- If mitigation is installed, arrange a post-mitigation test and retain the system documents.
- Continue periodic retesting, especially after changes to the home or how lower levels are used.
Frequently asked questions
Questions homeowners ask
Straight answers about the work, timing, and what to expect at your property.
What level does EPA recommend fixing?
EPA recommends fixing a home at 4 pCi/L or higher and says homeowners may consider fixing between 2 and 4 pCi/L. A test result should be interpreted in context and under the applicable protocol.
Is a short-term test enough?
It depends on the decision, result, method, and deadline. Short-term tests are common when time is limited, while long-term tests can better represent average conditions when time allows.
Where should a radon test be placed?
Montana DEQ and EPA materials point to the lowest level suitable for occupancy, in a regularly used room and away from conditions that can bias the device. Follow the device instructions and current professional standard.
Should the installer perform the post-mitigation test?
EPA consumer guidance recommends an independent follow-up measurement to avoid a potential conflict of interest, even if the installer performs an initial check.
Bring the right details to the estimate
Share the test result, foundation type, ZIP code, and deadline so our team can review a useful project summary.