Sub-slab depressurization systems are installed in buildings with slab (concrete) floors.
It consists of PVC piping installed through the slab floor and fan connected with the piping. When the system is on, the fan applies a vacuum beneath the slab and the vapors in the soil beneath the building are directed outside, as shown above. It is most common and reliable active system depressurization method.
Sub-membrane depressurization systems are installed in houses with earthen or gravel crawl spaces or floors instead of slabs. With sub-membrane depressurization systems, an impermeable membrane(such as plastic sheeting) is placed over the earthen or gravel area and the ventilation piping is installed through the membrane
Water drainage systems are often installed under or around foundations to provide a means for collecting and diverting storm water away from home. These can be major conduits through which radon laden soil gas can find its way into a home. If vacuum applied to water drainage area, radon can easily be collected from pathway it is following.
DTD pulls the radon gas and other soil gas by creating a vacuum within the existing drain tile network of a sump or drainage system. This method allows the radon mitigation system to communicate with the soil surrounding the drain-tile system more easily.
Suction is created on floor-to-wall joint (and adjacent block wall) to collect radon and exhaust it outdoors.
Radon laden air is collected from voids in block walls and exhausted to a safe location outdoors.