After your initial radon test, a retest is crucial to confirm whether levels are truly safe or if mitigation is needed. Radon can fluctuate due to weather, ventilation changes, or seasonal shifts. A retest, typically over 2-7 days, captures a more accurate average. It gives real peace of mind before buying a house or finishing a basement. Skipping this step might leave you unaware of hidden risk. radon retest 8