Radon and Radon Testing
Radon is a radioactive, colorless, odorless gas that occurs as a natural byproduct of the radioactive decay of uranium and radium. Their child, radon, contributes a significant part of normal background radiation that is present all over the earth. Small amounts of these radioactive elements may be found in the rocks of the earth – particularly in some granites and shales, in the soil and in groundwater.
Radon is the heaviest of the noble gases – about eight times denser than normal air. Because of this, it tends to accumulate in low lying and confined areas. There, it can build to concentrations high enough to be regarded as a potential health risk.
Statistics suggest that prolonged radon exposure is a contributing factor in 20,000 lung cancer deaths per year in the United States alone. The Surgeon General has warned that radon is the second leading cause of lung cancer in the United States – behind smoking. Smokers and small children are considered to be more at risk when it comes to radon exposure. Statistics also show that exposure to radon causes more annual deaths than drunk driving, drowning and home fires.
While no amount of radon exposure can be considered 100% safe, we will always have some exposure to a low level of background radon radiation. While the amounts of radon vary by geographic area, the national average concentration of outdoor radon is about 0.4 picoCuries per liter (pCi/L) for the United States. Ideally, radon levels inside a home should be the same as outdoors, but these results are difficult to achieve. The average indoor radon concentration is 1.3 pCi/L.
Currently, the EPA recommends that radon levels exceeding 4.0 pCi/L be lowered by installing a radon removal system.
How Do We Know If We Have a Radon Problem?
There are several methods of testing for radon. While there are some very elaborate, electronic, high tech and expensive devices which can monitor radon levels on a continual basis, most radon tests utilize some form of collector which gathers the radon effects over a period of days, weeks or even months. Ventilation and external factors such as rains can affect radon levels on a short term basis. Radon levels in a home can fluctuate from day to day, even from hour to hour. Sometimes longer term or repetitive tests may be necessary to get the most accurate results.
Given the skill required to make an accurate assessment, the low cost and reliability of an unbiased, professional, qualified radon tester is a good investment. For a home owner or a home seller wanting to put a house on the market, a long term test is recommended to give a good indication of the average radon level over time. Likewise, a home buyer wants the assurance that a house is free from dangerous radon levels but requires faster results using a short term test.
Whichever methods are used, remedial action should be taken if repeated or long term radon levels exceed 4.0 pCi/L.
And Then What Should We Do?
The majority of methods for mitigating radon in a home have to do with preventing or reducing radon’s entry into the home.
Some common remediation methods include:
Many newer homes have been built with techniques that help to lessen radon accumulation. Still, this should not be regarded as making them absolutely radon proof. And many older homes were built before any awareness of radon or methods to mitigate it. It is estimated that 7-8% of the homes in the United States have elevated radon levels and present a long term risk to inhabitants.
Often, the cost for radon remediation is insignificant when compared to the potential risks associated with radon exposure.