Radon gas is naturally occurring, it is odorless and colorless. It is also known to cause lung cancer by the EPA. Because of this inability to see it with a naked eye, there are still some people who do not believe that it exists. There is plenty of science and research behind this. If someone tells it does not exist, they are immediately discrediting themselves from this topic.
Radon comes from the breakdown of uranium that is found in the soil and the gas rises through the soil and enters homes from the lower levels through cracks in the concrete, gaps around waste pipes, sump pumps pits, or through the soil in the crawl space. The topic of radon testing usually comes up as part of a home inspection when a home is being purchased.
In the States that license people who test for radon gas there are described locations that are accepted as proper locations to test for radon gas. In Ohio, the testing location is the lowest livable space in a home for a minimum of 48 hours. Lowest livable space typically is a basement. The basement does not have to be finished to be considered a livable space. The radon testing equipment in Ohio needs to be placed in the lowest livable space at least 20 inches off the floor, at least 2 feet from an exterior wall, etc.
One myth regarding testing is that if the home does not have a basement then there is no need to test. This is not correct. Higher than desired radon levels are found in homes built on a slab.
Another myth is that if the home is built on a crawl space then there is no need to test for radon. This also is not correct. If the crawl space is well ventilated to the exterior this may reduce the odds of radon entering the home, it is definitely however not a certainty.
A third myth we often hear is that if the home has a walkout basement then there is no need to test. This is based upon the belief that since there is a door to the exterior then the air entering the home will be exterior air and not soil gas entering that lower area of the home. This also is not true. Walkout basements can and do test higher than the EPA recommends.
I have had sellers tell me that they were told by friends what to do to their home to lower any potential radon levels. These methods involved opening windows typically and airing the place out. This may or may not help. Radon enters the home mainly due to a chimney effect where temperature and air pressures make it easy for soil gas to flow into the lowest part of the home and then flow upwards through the home like smoke and heat flows through a chimney. Opening a window can increase the airflow and suck more soil gas and radon into the home.
The best radon monitors will detect movement, temperature, humidity and air pressure. If the monitor were to be moved to the exterior the monitor will record it and the test will be invalid and another test will need to be redone, this time at the expense of who interfered with the test.
Radon is a naturally occurring radioactive gas that is a known cause of lung cancer. There are myths regarding testing for the gas. The gas makes its way towards homes through the soil underneath homes and eventually enters homes. The only way to know for certain what the radon levels are in a home is to test no matter the design of the home.