What typically needs to be done
- Retesting uses an approved test device/kit in the lowest level of the home that is regularly occupied or could be occupied, following the device placement rules.
- Short-term tests require the specified closed-house conditions; long-term tests average conditions over a longer period and have different handling requirements.
- Results and dates are stored with the home record, and elevated results are handled according to current public-health guidance for confirmation testing/mitigation.
What you can check or prepare yourself
- Place the device away from drafts, high humidity and locations the kit instructions exclude.
- Do not move, cover or disturb the test during the measurement period.
- Retest after major renovations, HVAC/ventilation changes or mitigation-system changes when current guidance recommends it.
- If the home already has a mitigation system, note the fan/monitor indicator condition but leave fan/piping service to a qualified radon professional.
Step-by-step reminder
- Use a radon test method appropriate for the home and follow the device or laboratory instructions exactly.
- Place the test in the recommended lowest lived-in level and maintain the required closed-house conditions when applicable.
- Record the result and test date with the home's records.
- If results are elevated, follow current public-health guidance and consult a qualified radon professional about confirmation testing or mitigation.
Do not interpret a single test outside the test manufacturer's instructions. Follow current EPA/state/local guidance for testing and mitigation decisions.
Before you start
Review the manual for the exact appliance, system or material in your home before opening panels, disconnecting utilities, changing settings or using chemicals. Model-specific procedures and local installation details can differ from a general guide. Shut off power, water or fuel only when the manufacturer procedure calls for it and you are comfortable identifying the correct control. Stop if the condition you find is different from what is described here.
When to bring in a professional
The homeowner checks above can help you understand the condition of the system and prepare for service, but the higher-risk portion may require specialized tools, safe access, combustion/electrical knowledge, refrigerant work, pressure equipment or a qualified inspection. Use the typical-work list to understand what a proper service visit should cover, and hire the appropriate professional for work outside normal homeowner access.
This guide is general information, not a home inspection or a guarantee that a procedure is suitable for your specific equipment or conditions. Follow manufacturer instructions and applicable codes, stop if anything appears unsafe or different from the guide, and use a qualified professional when appropriate. Read the site terms and limitations.