When to Mitigate

The action level in Illinois is 4.0 pCi/l (pico-curies per liter). If your home has a radon concentration of 4.0 pCi/l or more, a radon reduction system is strongly recommended. Opening windows and ventilating the house is not good enough to bring radon levels safely down. In theory this may work, but it takes only 12 hours for radon to reach its maximum concentration in the home. Also, the radon levels may actually increase by having windows open due to the stack effect, i.e. the difference in pressure which accelerates the air movement. In winter, the home could be completely closed up for several months except for going in and out of the house (which doesn't leave enough time for the gas to be diluted). This is why only a continuous radon reduction system will safely and quietly remove the gas from under the house before it ever enters.

How do I know if I have Radon in my home?

Any house can have high radon levels. It doesn't matter whether the house is a new construction or an older home. Even if neighbouring homes have low radon levels the radon level in your house may still be high. Although the IEMA provides maps with an approximation of the radon levels in different Illinois counties, these are only guidelines. Even if you live in a county with generally low radon levels, your house may have high radon levels. The only way to find out is to test your home for radon. This can be done either by a Licensed Radon Meassurement Professional or by buying a radon test kit from the IEMA or at a local hardware store.