Test Radon et Atténuation

Radon test should be conducted in the lowest livable level. Short-term test minimum 48 hours (2-7 days). Long-term test 90+ days for more accurate results.

1. Place test kit in lowest livable level (finished basement or ground floor)

2. Test location should be in a regularly used room (not bathroom, kitchen, or laundry)

3. Place detector 2-6 feet above floor, away from exterior walls and windows

4. Keep windows and doors closed during test (except normal entry/exit)

5. Do not place near drafts, fans, or HVAC vents

6. For short-term test: leave in place minimum 48 hours (ideally 4-7 days)

7. Record start and end times, send to lab promptly after test period

8. Action level: 4 pCi/L (picocuries per liter) — mitigate if at or above this level

- Test placed in wrong location (too close to window, door, or vent)

- Test period too short (less than 48 hours)

- Windows left open during test (dilutes radon, gives false low reading)

- Test placed in room not used as living space

- Test during unusual conditions (high winds, construction)

- Test kit expired or improperly handled

Active soil depressurization (ASD) is the most common mitigation. Fan must run continuously. System should reduce radon to below 4 pCi/L, ideally below 2 pCi/L.

1. Check the radon fan is running — feel for vibration or listen at the pipe

2. Read the U-tube manometer or pressure indicator — fluid levels should be unequal (indicates suction)

3. Verify the vent pipe extends above the roofline and is properly capped

4. Check that the vent pipe is sealed where it penetrates the slab

5. Verify the fan is accessible for maintenance/replacement

6. Ask for post-mitigation test results — should show below 4 pCi/L

7. Check fan label for installation date — typical fan lifespan is 5-10 years

8. Verify system label with installer name and contact information

- Fan not running (burned out — system is not working)

- U-tube showing equal fluid levels (no suction — system failed)

- Vent pipe not extended above roofline (exhausts radon at living level)

- Slab penetration not sealed (reduces system effectiveness)

- No post-mitigation test conducted

- Missing system label/installer info