In the not-so-distant past, most homes leaked so badly that the air inside would be exchanged on a regular basis with no help whatsoever. The leaking and changing of air in a home often contributed to venting radon gas, and bringing fresh air into the home, but not necessarily removing the gas to safer levels or creating better indoor air quality.
Today, with higher insulation levels and the use of house wraps that are properly installed, the leaking is much reduced.
- Sealing of homes has reduced built-in air exchange, trapping more radon gas within homes, so additional systems must be incorporated.
- Most residential air conditioning/ heating systems are not designed to bring in fresh air, but recirculate the air within the building.
Conforming to EPA guidelines is easy
Installation of the remediation system is relatively low-cost when compared to the cost of building a home or undertaking a major renovation. The amount of work required to make a home conform to the EPA guidelines for radon remediation is very small, and not difficult.
With more people incorporating green building techniques, many builders are responding and including the remediation systems in their projects.
- A naturally occurring gas formed by the decay of uranium that is found in nearly all soils.
- A known carcinogen as classified by the World Health Organization (WHO), the National Academy of Sciences, the U.S. Department of Health and Human Services, as well as EPA, because of its proven links to lung cancer in humans.
Health issues and exposure concerns:
- When a home or any other structure is built, radon is trapped within the structure after it enters the building through the basement, crawl space, or slab through holes or cracks or piping.
- Levels between or above 2 and 4 pCi/L are recommended by the EPA to be remediated.
Remediation of radon:
- Remediation systems are similar if they are installed during construction or retrofitted. You must create a void either by installing gravel or a system of open piping below the slab, and install either a passive or mechanical vent to the exterior. All cracks and gaps must be sealed in the slab to ensure that radon is not seeping into the home.
- Many states require a licensed radon remediation contractor to design and install the system.
- In new construction, a system is installed to exhaust the gas from beneath the basement or main slab to the exterior, properly sized to keep the levels below the recommended level of 4 pCi/L.
- For an existing structure, testing must be performed to determine if remediation is required. A testing canister is placed within the structure for three days. The canister is then removed and tested in a laboratory to determine the level of radon within the structure. If the levels are determined to be too high, a licensed radon contractor can design a system to remediate the radon.
A second three-day test must be performed after the installation of the venting equipment to determine if the levels are below the required maximum.
More information on EPA’s radon website: www.epa.gov/radon