Radon Gas in Homes and Lung Cancer
by: Mark J. Donovan

Unsuspecting homeowners may not realize the full risks associated with Radon gas in their homes. Increasing evidence suggests that Radon gas is the most underestimated cause of Lung Cancer. Radon gas can occur anywhere, however some areas of the United States are known to have abnormally high levels of this potentially deadly gas. Though Radon gas can be found in every state, the highest concentration levels are in the Northeast and the upper Midwest of the United States.

If Radon gas can be dissipated from homes and into the atmosphere it is relatively harmless. However, when Radon enters homes and stays trapped, which can frequently happen with today's more tightly sealed homes; the gas can become a health problem.

The Radon gas typically enters a home from a basement. If the basement is not adequately vented to the outside atmosphere the gas can build up to high levels within the home.

There are differing opinions about the minimum safe levels, however the evidence continues to grow that Radon may be the most underestimated cause of lung cancer. Radon gas may be particularly more dangerous to children, smokers and those who spend much of their time indoors.

When purchasing a new home, make sure a Home Inspection is performed and that the Home Inspector checks for Radon levels. The cost for a Radon test is minimal and well worth it. If high levels of Radon gas are detected proper ventilation systems should be added to the home. The costs of such ventilation systems are again quite reasonable.

About The Author
Over the past 20+ years Mark Donovan has been involved with building homes and additions to homes. His projects have included: building a vacation home, building additions and garages on to existing homes, and finishing unfinished homes. For more home improvement information visit http://www.homeadditionplus.com and http://www.homeaddition.blogspot.com.

Where does Radon come from?

Radon comes from the natural radioactive decay of radium and uranium found in the soil beneath the house. The amount of radon in the soil depends on complex soil chemistry, that varies from one house to the next. Radon levels in the soil range from a few hundred to several thousands of pCi/L. The amount of radon that escapes from the soil to enter the house depends on the weather, soil porosity, soil moisture, and the suction within the house.

Houses act like large chimneys. As the air in the house warms, it rises to leak out the attic openings and around the upper floor windows. This creates a small suction at the lowest level of the house, pulling the radon out of the soil and into the house. You can test this on a cold day by opening a top floor window an inch. You will notice warm air from the house rushing out that opening; yet, if you open a basement window an inch, you will feel the cold outside air rushing in. This suction is what pulls the radon out of the soil and into the house. You might think caulking the cracks and the openings in the basement floor will stop the radon from entering the house. However, scientific studies show, it only takes enough unsealed cracks or pin holes in the caulking to equal a hole 1/2" in diameter to let all the radon in. It is unlikely that caulking the accessible cracks and joints will permanently seal the openings radon needs to enter the house. The radon levels will still likely remain unchanged.

Fortunately, there are other extremely effective means of keeping radon out of your home. Throughout the country, several million people have already tested for radon. Some houses tested as high as 2,000-3,000 pCi/L; yet, there hasn't been one house that could not mitigate to an acceptable level. Mitigation usually costs between $500-$1500.

What should I do about the levels of Radon in my home?

The following represents an opinion, based on an understanding of the radon issue from several sources.

  • If the house tests above 20 pCi/L most experts agree it is prudent to install a system that can permanently reduce your families exposure to radon.
  • If the house tests below 4 pCi/L most experts agree that there is a relatively low probability of significant health risk at this low level of exposure. However, we recommend retesting the radon levels once you move in, to verify this low reading. Industry surveys show that up to 30% of the radon tests in real estate transactions are subject to some ventilation. LET THE BUYER BEWARE. We once tested a house, that measured 168 pCi/L in a child's bedroom. The selling agent ordered a retest by a tester known to test on the second floor with the windows open. He told my clients the house only measured 3.5 pCi/L and they didn't have a radon problem. Although he never gave my clients a written report stating this.
  • If the house tests between 4 and 20 pCi/L there is no need for immediate panic, but you will have to make some difficult decisions. About 50% of the houses we test fall in this gray area. The average Colorado home measures 5.9 pCi/L. The national average is 1.5 pCi/L and outside air measures about 0.35 pCi/L. The closer to 4 or 20 pCi/L the easier the decision should be. The most difficult decisions are in the 10 to 12 pCi/L range.
Who We Recommend:

Echo Home Inspection Inc.