What Is Radon & Why All Radon Mitigation Systems Are Not the Same
Radon is a naturally occurring radioactive gas produced by the breakdown of uranium in soil, rock, and water. It is invisible, tasteless, and odorless, making it impossible to detect without proper testing. Radon can enter homes through foundation cracks, sump pumps, and gaps in floors or walls, but even when a foundation floor is totally sealed, radon still pressurizes through the floor, accumulating to levels that are hazardous to health. Long-term exposure to radon is linked to lung cancer, and suspected in Leukemia and Lymphoma cases. It is considered a class 1 carcinogen by the EPA, similar in severity to cigarette smoking.
Each pCi/L of radon in a home produces seven alpha particle disintegration impacts in the lungs every second, and even levels considered below the Federal Action Point of 4 pCi/L can pose significant health risks over time. 4.0pCi/L is equivalent to smoking 5.3 cigarettes every 18 hours of exposure, and 200 chest X-Rays per year in REM exposure. It was never meant to be a “health” standard, but simply what the Federal Government felt was an “achievable” radon rate for mitigators in the U.S. Many countries throughout the world have moved to the World Health Organizations Action Point of 2.7pCi/L over the last 17 years, for a better “health” related standard. The U.S. has an average radon rate of 1.25pCi/L in homes, producing 21,000-25,000 deaths from radon induced lung cancer per year. The State of Wisconsin has an average radon rate 8 times higher than the average U.S. radon rate.
Radon mitigation systems are designed to reduce radon levels indoors, but not all systems are created equally. Just as cars, homes, or appliances vary in quality, performance and price, radon mitigation systems differ in their effectiveness, design, guarantees, and cost. Choosing the right system involves more than simply comparing prices. Homeowners need to consider company experience, fan and system warranties, past customer reviews, and guarantees for achievable radon levels. A high-quality mitigation system focuses on reducing radon to below 2.0pCi/L, which has always been the “highly recommended” threshold by the EPA, not just meeting the Federal “Action Point” of below 4.0pCi/L, providing a true safety standard for your home.
Fan selection and installation are crucial factors in system performance. While most mitigation fans come with a five-year manufacturer’s warranty, some mitigation companies charge significant labor fees to replace a fan under warranty. The best companies include labor at no additional cost, ensuring that the system continues to operate effectively without unexpected expenses. The fan’s flow capacity must match the home’s requirements, and the piping diameter and layout are critical. Systems that fail to deliver the proper airflow may only be able to reduce radon rates to just below 4.0pCi/L, a Federal failure point, leaving occupants at higher risk.
Flow dynamics are a critical aspect of mitigation system success. A system works by creating a vacuum beneath the slab or basement floor, drawing radon gas away from the home and exhausting it safely outside. Homes in areas like Southeast Wisconsin mostly require 120–140 CFM to achieve adequate sub-slab vacuum. Some homes or commercial buildings require rates over 500 CFM to get to full vacuum. Using exhaust piping that is too small or a fan that is undersized will reduce the system’s efficiency and limit the achievable reduction of indoor radon levels. Properly designed systems consider both the home’s size and the radon level to ensure consistent, long-term performance.
Federal certification is required for anyone installing a radon system in the U.S. Certification is granted to individuals, not companies, and can be verified through the National Radon Proficiency Program (NRPP). Certified installers have the training and expertise to correctly assess home conditions, design a mitigation system, and ensure proper installation. Homeowners should request the installer’s certification number and verify insurance coverage that specifically applies to radon mitigation. Many companies advertise radon services but do not employ certified professionals, which can result in ineffective or unsafe systems, or systems that need to be physically corrected to meet Federal Standards, which is a requirement.
Radon mitigation is not a single design solution that works equally for every home. Factors like soil composition, home design, HVAC system operation, and seasonal pressure changes affect how radon moves through a house. Homes with deeper or larger basements, sealed foundations, forced-air heating, or extremely high radon rates, may require more complex mitigation designs. Skilled installers assess each property individually and develop a system tailored to the home’s specific needs, ensuring optimal radon reduction. The assessment should be done in person, not by someone quoting a system over the phone without seeing the property.
Testing is essential before and after mitigation. Without accurate measurements, there is no way to know if a system is performing correctly. Continuous monitoring or follow-up tests confirm that radon levels remain safe and that the system is functioning as designed. Federal Standards dictate that a radon mitigated house or building be retested every 2 years. Regular maintenance and inspections can prevent declines in performance over time.
Choosing the right radon mitigation system and installer requires careful consideration of more than just cost. Flow dynamics, proper installation, certified technicians, warranties, and realistic guarantees all affect long-term effectiveness. Homeowners who prioritize these factors can reduce radon levels safely and protect the health of everyone in the household.