Check the radon system's warning indicator without opening it
A radon-reduction system can look unchanged even when its fan or airflow is no longer working as intended.
When it usually needs attention
Ongoing home-care habit
EPA says to look at the system warning device regularly; the installer instructions define the normal indication.
When this guide applies
Only applies when a radon-reduction system is confirmed.
What to do
Find the system label and warning device, compare the visible reading or light with the installer instructions, and record any change without adjusting the system.
Applies when: Only applies when a radon-reduction system is confirmed.
Who should handle it: Residents may observe a labeled indicator; testing, diagnosis, fan replacement, piping, electrical work, and system changes belong to the responsible owner and a qualified radon professional.
Tools
- Installer or system instructions
- Flashlight
- Phone camera or written log
Parts and supplies
- No replacement part for observation
Safety gear
- None for an accessible visual check
Before you start
- Identify the warning device and its normal indication
- Keep the system label and installer contact available
Power, water, or fuel shutoffs
- Do not unplug or switch off a radon fan for this check
Cleaner or chemical limits
Use no cleaner, lubricant, sealant, or spray on the fan, gauge, alarm, pipe, or electrical parts.
Stop and get help when
- Do not climb, open a fan or electrical box, disconnect piping, or enter an unsafe crawlspace or attic
- Treat an alarm, stopped fan, damaged pipe, unusual noise, or changed gauge as a service condition
Who to call: Use a qualified radon mitigation professional and the responsible owner for diagnosis, repair, or uncertain operation.
Reviewed sources
- Maintaining a Radon Mitigation SystemU.S. Environmental Protection Agency · reviewed July 13, 2026