Ultimate Guide: What is Radon?

Radon is a silent threat that may be present in your home without your knowledge. As a naturally occurring radioactive gas, radon is the second leading cause of lung cancer in the United States, responsible for about 21,000 deaths annually, according to the Environmental Protection Agency (EPA). Despite its danger, many people are unaware of its presence or how to mitigate it.

This guide will help you understand radon, its health risks, how to detect it, and the best methods to reduce its impact on your home and family.

What is Radon?

Radon is a radioactive gas produced by the natural decay of uranium, radium, and thorium in soil and rocks. It is invisible, odorless, and tasteless, making it undetectable without specialized tests. Radon enters homes through cracks in foundations, walls, and other openings that touch the ground. In poorly ventilated spaces, it can accumulate to dangerous levels over time.

Key Facts About Radon:

• Source: Radon forms during uranium, radium, and thorium decay found in soil and rocks.

• Properties: Invisible, odorless, and tasteless.

• Entry Points: Cracks in floors, walls, and foundations; gaps around pipes.

• High-Risk Areas: Basements and crawl spaces with limited ventilation.

• Detection: Specialized radon test kits or professional assessments are required.

Characteristics and Properties of Radon

Radon originates from the natural radioactive decay of elements like uranium in soil and rocks. Once released, it can enter the air and accumulate indoors. Levels of radon vary depending on factors such as geography, soil composition, and building ventilation. In tightly sealed homes, radon levels can increase due to poor airflow.

As a dense, inert gas, radon belongs to the noble gases group on the periodic table, with the atomic number 86 and the symbol Rn. While chemically stable, it can form compounds like radon fluoride (RnF₂) under specific conditions. Its boiling point of -61.7°F (-52°C) makes it a gas at typical indoor temperatures, and its emissions of alpha particles during decay pose significant health risks when inhaled.

Isotopes of Radon

Among radon’s 37 isotopes, radon-222 is the most notable because of its 3.8-day half-life, which allows it to remain active long enough to accumulate in enclosed spaces. Its high radioactivity poses significant health risks, particularly in poorly ventilated areas where levels can rise unchecked. While other isotopes like radon-220 and radon-219 decay more rapidly, reducing their presence indoors, radon-222’s persistence makes regular testing and mitigation essential for maintaining safety.

Health Risks of Radon Exposure

Radon exposure is the leading cause of lung cancer among non-smokers. When inhaled, radioactive particles from radon decay can damage the DNA in the cells lining the airways, increasing cancer risk. Smokers face even higher risks due to the combined effects of radon and tobacco.

Key Health Impacts:

• Lung Cancer: Radon contributes to about 21,000 deaths annually in the U.S.

• DNA Damage: Radon particles harm the cells lining the lungs, leading to long-term health effects.

• Increased Risk for Smokers: Smokers exposed to radon are 25 times more likely to develop lung cancer than non-smokers.

• Long-Term Exposure: Radon’s effects are cumulative and may go unnoticed for years before symptoms develop.

Testing and Mitigation: Protecting Your Home

Indoor and Outdoor Radon Levels

• Indoor Levels: Radon levels in buildings can range from 10 Bq/m³ to over 10,000 Bq/m³. (Bq/m³, or becquerels per cubic meter, is a unit that measures the concentration of radon gas in the air. Higher values indicate more radon particles in a given volume of air.)

• Outdoor Levels: Typically very low, ranging from 5 Bq/m³ to 15 Bq/m³, which poses minimal risk.

Testing for Radon

Testing is the only way to know if radon is present in your home. Short-term and long-term radon test kits are widely available, and professional testing services can provide more precise measurements.

Steps to Test for Radon:

1. Purchase a radon test kit or hire a certified radon testing professional.

2. Place the test in the lowest lived-in area of your home, such as a basement.

3. Follow the test kit’s instructions, typically leaving it in place for 2-7 days for short-term tests.

4. Send the test to a lab (if required) and review results measured in picocuries per liter (pCi/L), a unit that measures the radioactivity concentration in the air. Specifically, it quantifies the number of radioactive disintegrations occurring per liter of air each second.

5. Conduct long-term tests if initial results are near or above 4 pCi/L for a more accurate assessment.

The EPA recommends taking action if radon levels exceed 4 pCi/L, but even lower levels can pose risks over time.

Reducing Radon Levels

Mitigation techniques can effectively lower radon concentrations in your home. “Installing a sub-slab depressurization system or sealing cracks can significantly affect radon levels,” says Kaber Robinson of Arizona Radon, LLC. “The key is working with certified professionals to ensure the job is done right.” Professional contractors certified by the NRPP or state agencies are best equipped to handle these solutions.

Common Mitigation Methods:

• Sub-Slab Depressurization: A vent pipe system and fan remove radon from beneath the foundation and vent it safely outside.

• Sealing Cracks: Use caulk or sealants to close gaps in floors, walls, and foundations.

• Improved Ventilation: Increase airflow in crawl spaces and basements to dilute radon levels.

• Heat Recovery Ventilators (HRVs): Exchange indoor air with fresh outdoor air while maintaining energy efficiency.

• Sump Pump Covers: Install airtight covers to prevent radon entry through sump pits.

Who is at Risk?

Any home can have a radon problem, regardless of age, design, or location. Both new and old homes, well-sealed and drafty homes, and homes with or without basements are susceptible. Testing is the only way to determine radon levels in your home.

Why Awareness Matters

Radon’s silent and invisible nature makes it easy to overlook, but regular testing and proactive mitigation can significantly reduce health risks. Public awareness campaigns and educational efforts are essential to ensure homeowners understand the dangers of radon and the importance of testing and remediation.

Conclusion

Radon may be invisible, but its impact is undeniable. Testing your home is the first step to protecting your family from this dangerous gas. With effective mitigation strategies, you can ensure a healthier living environment for years to come. Don’t wait—take action today to safeguard your home and loved ones.