Active Soil Depressurization

HOW ACTIVE SOIL
DEPRESSURIZATION (ASD) WORKS

An ASD system effectively prevents radon entry into a home by controlling the pressure differential that drives soil gas from beneath the home to the interior of the home. Radon is drawn from beneath the slab by a radon exhaust fan and the radon gas vents to the outdoor air above the home where it quickly dilutes into the atmosphere.

The radon exhaust fan does not interfere with the heating and air conditioning of the home, so you are protected when the air is turned off and the windows are closed. This system also removes moisture and other pollutants that can enter the home from under the slab so that it improves the overall indoor air quality.

Utility costs to operate one fan is low. It uses the basically the same amount of electricity s a 100 watt light bulb. Very little noise is associated with an ASD system if properly installed. System failure is detected by a either an electric meter or a pressure sensing device (u-tube manometer). This device will be located visible to the homeowner. Either the electric meter or the pressure gauge will only indicate if the system is functioning and not the indoor radon level.

The EPA recommends testing at least once every two years, even after a radon mitigation system has been installed. The only maintenance with a radon mitigation system is to read the electric meter or the pressure gauge to ensure your ASD system is properly functioning.