Date Published: 05/28/2010 [Source]
Overview
Because the second top cause of lung cancer is radon, it is advisable to minimize your contact with radioactive gas. Although the exact amount of radon exposure that is safe for humans is unknown, according to the United States Environmental Protection Agency, or EPA, the agency recommends that homeowners reduce the amount of radon in their home if levels reach 4 picocuries per liter or higher. Facts About Radon
Radon removal systems help decrease the amount of radon present inside a structure. Radon typically originates in soil underneath property. It then enters the enclosed space through available openings, such as doors and cracks, when warm air rises inside, creating a vacuum that draws air, radon and other gases into lower parts of the structure. The radon trapped inside then becomes concentrated, causing levels to rise if the gas is not removed.
Function of Radon Removal
Sometimes removing the radon inside a structure simply requires closing cracks--with caulk, for example--and then sealing open areas near the ground level to stop radon from gaining entry. If that method is ineffective or not possible, the next step is to hire a qualified professional, such as a contractor with state certification in radon mitigation, to install a mitigation system capable of pushing radon away from the foundation of the structure. Features of Radon Removal Systems
The goal of radon removal systems is to stop radon from gaining access to the inside of an enclosed structure, the preferred technique, or to reduce the amount of radon present after the gas enters an enclosed structure. The precise method that contractors use depends on the type of structure involved, particularly the design of the foundation.
Types of Radon Removal Systems
Effective radon removal systems are usually variations of the soil suction procedure, modified based on the foundation design involved. For example, structures with a concrete basement may require block-wall suction, drain-tile suction or sump-hole suction. Each method draws radon from beneath a structure after the contractor uses a pipe to create a suction vent in the relevant location, such as the drain tile or sump pump.
Alternatively, structures with crawlspaces, or shallow areas under the ground floor, may require submembrane suction, which places a suction vent beneath a heavy plastic sheet inserted above the earth under the property. Structures with a slab-on-grade foundation consisting of concrete poured directly on the ground usually need subslab suction, which relies on a suction vent inserted through the concrete foundation into the earth underneath.
Considerations
Radon removal systems may also incorporate active or passive suction. Active suction, which is also called depressurization, uses a fan to facilitate the removal of radon from an enclosed structure, while passive suction uses air currents and differences in pressure to achieve the affect of a fan. The first method is more common and reliable.