Radon Remediation / Radon Mitigation
Radon Remediation | Radon Mitigation
Radon remediation is needed when a building (or house) is found to have an elevated level of radon gas (defined by the U.S. Environmental Protection Agency as a radon result of 4.0 pCi/l or higher,) mitigation methods of reducing the radon levels can be applied to cure the problem. The most common method of radon remediation (also known as radon mitigation or radon gas abatement is Active Soil Depressurization (ASD.) An ASD Radon Mitigation System utilizes PVC piping attached to an electric radon suction fan. The piping typically begins below the lowest floor of the structure’s foundation (penetrating the slab of the basement or the plastic membrane of the crawl space) and extends upward to an exit point above ground level. The inline radon fan is mounted in an inconspicuous location on the exterior or within an attic above the home. In cases where the radon fan is installed in the attic, the discharge pipe extends out through the roof so the radon gas can be released outdoors. Once radon is released into the atmosphere, it is no longer hazardous. Radon is only dangerous when trapped indoors.
Reduce Radon Gas by 99%*
Active (fan assisted) radon remediation systems can reduce the radon gas entry by as much as 99%. A qualified radon contractor (also known as a radon mitigator or radon remediation specialist) can typically install a radon mitigation system in a home in less than a day. After the system is installed, the radon levels begin to drop almost immediately. Passive radon reduction techniques (such as sealing cracks or installing pipes without an inline radon fan) are rarely effective at reducing radon levels. The reason that these “passive” radon reduction techniques are ineffective is because radon gas is under pressure and must escape from the ground. It is a very inert, un-reactive gas that can be drawn up through the pours of concrete, around drains, utility penetrations, or expansion joints. Attempting to “seal out” radon is similar to trying to keep water out of a basement by painting the walls and floor with waterproofing paint. It may work temporarily if the problem is minor, but it wouldn’t keep standing water out. The only way to fix a water problem is to redirect the water somewhere else before it enters the home.
The same principles apply to radon correction. Sealing cracks and openings is part of the radon remediation process; however this is to prevent the downward draw of conditioned air from the home and to improve the pressure field extension of the system below the slab, not to “seal out” the radon. Radon is a colorless, odorless, naturally occurring, radioactive noble gas that is formed from the decay of radium. Radon gas is one of the heaviest substances that remains a gas under normal conditions and is considered to be a health hazard. The most stable isotope, Rn222 (Radon Gas), has a half-life of 3.8 days and is used in radiotherapy. While having been less studied by chemists due to its radioactivity, there are a few known compounds of this generally un-reactive element. Radon is a significant contaminant that affects indoor air quality worldwide. Radon gas from natural sources can accumulate in buildings, especially in confined areas such as the basement. Radon can be found in some spring waters and hot springs.
Radon Remediation Systems: Life-Savers
According to the United States Environmental Protection Agency, radon is reportedly the second most frequent cause of lung cancer, after cigarette smoking; and radon-induced lung cancer the 6th leading cause of cancer death overall. According to the same sources, radon reportedly causes 21,000 lung cancer deaths per year in the United States. Because of this, radon remediation systems can be life-savers. Indoor radon can be mitigated by sealing basement foundations, water drainage, or by sub-slab de-pressurization. In severe cases, radon remediation can be achieved via air pipes and fans to exhaust sub-slab air to the outside. Indoor radon ventilation systems are less visible, but exterior radon systems can be more cost-effective in some cases. Modern construction that conserves energy by making homes air tight exacerbates the risks of radon exposure if radon is present in the home. Older homes with more porous construction are more likely to vent radon naturally. Ventilation systems can be combined with a heat exchanger to recover energy in the process of exchanging air with the outside. (This is more common with commercial and industrial radon mitigation.) radon collector installed under a radon barrier (a sheet of plastic that covers the crawl space). The most common approaches are active soil depressurization (ASD) which utilizes a radon remediation suction fan to pull the gas out from below the foundation of the home. The radon fan is attached in-line with a PVC pipe system running from the foundation to the roof of the home. Once the radon gas is discharged outdoors, it becomes diluted by the outdoor air to levels that are not hazardous.