If you’re a homeowner, you need to know about the widespread problem of radon. A colorless, odorless gas, it is naturally radioactive and the second-leading cause of lung cancer. Radon usually enters the lowest levels of a home through the foundation. Since it is heavier than air, it tends to accumulate where it enters.
Uranium
Naturally-occurring uranium in soil and rocks undergoes radioactive decay, becoming a series of elements ending in lead. According to the Applied Techniques company, radon forms during this sequence after radium breaks down and before polonium is formed. It takes 4.5 billion years for one pound of uranium to decay into a half-uranium, half-lead mixture, so affected areas of the country will have radon virtually forever.
Seepage
An Environmental Protection Agency consumer guide to radon states that gases coming up from underground have slightly higher pressure than the air in your home. The difference in pressure pushes radon through small cracks in the house’s foundation. Radon enters your home’s lowest floor. If that part of the house has poor ventilation, it will stay there.
Water
Radon can also enter your home through well water, though this is less common than soil-borne radon. According to a study by the state of Maine, you can get a small dose of radiation from drinking radon-contaminated water, though inhaled radon poses a bigger problem. Radon can pass from water to the air during showering and bathing.
Radioactive Decay
Half of all radon atoms decay to polonium in about 4 days. Inhaled particles of polonium, a metal, will tend to remain in the lungs. Inhaled radon gives you a smaller radiation dose, since you exhale it. The polonium, because it stays inside your body, is the real hazard. Like radon, it emits alpha radiation. Outside your body, this form of radiation is relatively harmless—it can’t penetrate your skin. Inside your organs, however, it can be deadly.
Remediation
According to the Environmental Protection Agency, costs of radon remediation in 2010 range from about $800 to $2500. The work done to the home varies by its construction, but typically, a contractor will install a fan-powered system to draw air from underneath the foundation and vent it outside. They will also examine the foundation for cracks and seal them.
