Radon in Nature
Radon gas is produced during the radioactive decay of uranium and thorium, common throughout the Earth. They slowly disintegrate into lighter radioactive elements like radium, polonium, and lead isotopes. All are heavy metals except for one — radon gas, the heaviest gas in nature.
As it slowly oozes from the ground, radon is all around us in the air we breathe. Fortunately, it is well-diluted in the outdoor air. The average radon level in ambient air is 0.4 pCi/L (picoCuries per liter). Radon concentration is measured by the radioactivity it produces – 1 Curie is the radioactivity of 1 gram of radium.
Radon in Homes
Radon is the heaviest of all gases, eight times heavier than air. It accumulates in basements or on lower floors and then, diffuses throughout the building.
The average radon level in US homes is 1.25 pCi/L. About 1 out of every 15 homes exceeds the EPA’s “action limit” of 4 pCi/L and nearly 1 out of 6 homes exceeds the EPA’s “consider action limit” of 2 pCi/L.
Radon is a Potent Carcinogen
Radon gas decays into minute radioactive particles which float in the air we breathe. These particles get trapped in the lungs where they undergo radioactive decay with a half-life of 22 years. The radiation damages the DNA of adjacent cells and causes lung cancer.
- “Radon is the most potent environmental carcinogen to which the general public is exposed.” [2000 Report on Carcinogens]
- “Radon is the second leading cause of lung cancer.” [The Surgeon General]
- “Radon causes more deaths than home fires, drownings, and airplane crashes combined.” [US EPA]
- “Radon causes about 21,100 deaths in the U.S. each year.” [US EPA & The National Academy of Sciences, 2003 estimate]
Radon is the Leading Cause of Lung Cancer among Non-Smokers
The deaths of celebrities have raised public awareness about lung cancer among people who have never smoked. Smoking and radon are the two leading causes of lung cancer. Although lung cancer can be treated, the survival rate is one of the lowest among all cancers. From the time of diagnosis, only 11 to 15 percent of those afflicted will live beyond five years. But in many cases, lung cancer could have been prevented by quitting smoking or by radon mitigation in homes.
Smoking is the No. 1 cause of lung cancer. It is responsible for an estimated 160,000 deaths in the U.S. every year. Lung cancer has surpassed breast cancer as the number one cause of death among women.
Radon is the leading cause of lung cancer among non-smokers. Of the 21,000 deaths it causes every year, 2,900 occur among people who have never smoked.
Radon Mitigation Methods
Sub-slab depressurization systems draw concentrated radon gas from beneath the floor slab and exhaust it above the roof. Their cost varies from $800 to $2,500. They also pull heated or air-conditioned air from the house. EPA estimates that the average operating costs and energy losses are $150/year. Each radon stack emits about 1 Curie per year of heavy radioactive gas above the roof.
The most logical solution would be sealing the concrete and leaving radon in the ground but paints or surface sealers have proven ineffective against radon gas. However, there is now an alternative technology — RadonSeal Deep-Penetrating Concrete Sealer. It is not a surface sealer but seals deep inside the concrete.
Radon Mitigation with RadonSeal®
RadonSeal® Deep-Penetrating Concrete Sealer penetrates deep inside concrete (up to 4″), reacts with lime and alkali, expands into pores and capillaries, and cures. The concrete becomes permanently sealed against radon gas, as well as water and water vapor. Naturally, you also have to seal or caulk all openings in the basement, gaps, or cracks.
The RadonSeal mitigation method does not depend on mechanical equipment like a fan or on the power grid. There are no operating costs. The homeowner avoids the radon fan with unsightly piping around the house and saves $100’s of dollars on installation. Check out the Comparison of Radon Mitigation Methods
If your home already has a fan-based radon mitigation system, it still makes sense to seal the basement with RadonSeal. It will further reduce the radon level, lower the energy losses in exhausted treated air, and you will have a backup for equipment failures or grid outages. Besides, RadonSeal also provides waterproofing and damp proofing and preserves the concrete.