Radon is a highly radioactive, naturally occurring gas. It is both colorless and odorless so it cannot be detected in a home without a measurement device. Radon is produced deep underground as a byproduct of the decay of other radioactive materials such as uranium or plutonium. As it permeates to the surface of the earth it penetrates your home through the foundation, basement or crawl space where the occupants then breathe it in.
There are no immediate health effects of Radon exposure, however long term exposure can be very detrimental to the health of the buildings occupants, especially smokers who are already at a high risk for lung cancer. The danger becomes clear when you think about where you spend most of your time.
Since radon is radioactive, it is measured in picocuries per liter of air (pCi/L), which is simply a measure of radioactivity. A radon monitor takes air samples every hour and measures the picocuries of that sample.
The monitor needs to be placed in the home for at least 48 hours and left undisturbed in closed home conditions. This only means the windows need to be closed and the doors not left open, the occupants can remain in the home during the test and are encouraged to use the heating and air conditioning as usual.
The reason it takes 2 days is because radon levels fluctuate all day long and even seasonally, so a single test won’t give you an accurate idea of how much radon the home is receiving.
The EPA has designated three zones of radon exposure. Zone #1 is defined as areas with 4 pCi/L or higher, zone #2 is anything between 2 and 3 pCi/L, zone #3 is 1 or lower. The average outdoor level of radon exposure is about 0.4pCi/L.
The EPA recommends radon remediation measures be implemented in all Zone #1 areas, anywhere that averages a reading of 4 or higher.
If you live in Colorado, you live in a Zone #1 high radon zone. The state of Colorado department of public health and environment designates every single county in the state as “High radon potential” meaning probable indoor radon average.
See link below to view the map