The radon fan is installed on the exterior of the home. It creates a negative pressure under the home sucking the air through the PVC to the exhaust. The fan exhausts the radon above the roofline, where outside air can dilute the gas to safe levels. The fan has a moisture guard that helps to protect it from the elements and a guard on the exhaust pipe that prevents leaves, rodents, and debris from entering the system and damaging the fan.