Radon is a radioactive gas that exists naturally in the environment in very low concentrations.
Radon comes from uranium in the soil. While uranium is not present in significant quantities in most geographical areas, traces of uranium in the soil exist everywhere. As uranium breaks down, it produces radon gas.
Radon is classified as a human carcinogen. Breathing radon gas is associated with an increased risk of developing lung cancer. The risk increases with increased concentration of radon in the air and exposure time. The concern is around radon levels that can build up inside a house. Even if you live in an area with fairly low environmental radon, you could still have significant levels in your home.
You can get a relatively inexpensive test that will determine the radon levels in your home. Testing strategies fall into two general categories: short term testing, which may take only a few days; or long term testing, which could take several months. While long term testing gives you a better indication of the radon exposure, people often choose short term testing for faster results. Getting your home tested is a good first step and consulting an expert is always a good idea.
Understanding Radon Levels
Radon levels are measured in one of three different units:
• The most common unit of measure in the US is pico Curies per Liter (pCi/L), and the most common unit of measure in Canada being Becquerels per cubic meter (Bq/m³)
• You may also see the term working levels (WL), common in scientific literature
The following numbers are what you can expect to see:
• Average outdoor level is 0.3 pCi/L or 10 Bq/m³
• Average indoor level is 1.2 pCi/L or 45 Bq/m³
• Indoor action level in the United States is 4 pCi/L or 150 Bq/m³
• Indoor action level in Canada is 5.4 pCi/L or 200 Bq/m³
The action level is the level at which you should take steps to reduce the radon gas entering your home.