Finding Potential Health Hazards in Basements

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Radon is a colorless, odorless radio active gas that comes from the natural breakdown of radioactive metals in soil, rock, and water. When breathed into the body, molecules of radon lodge in the lungs and lead to an increased risk of lung cancer. The incidence of radon isn’t restricted to certain areas of the country. Radon normally moves up through the ground and into a house through cracks and holes in the foundation (though they are not the only source). Because it tends to concentrate in rooms closest to the ground, it’s particularly important to test for radon before converting a basement to living space. If test results indicate that there is a problem, radon reduction techniques are relatively easy to incorporate into remodeling plans.

Testing for Radon -- It’s fairly easy to test a house for radon. Don’t rely on tests performed on other houses in the area -- even homes that are next door to each other can have different levels of the gas. There are two basic types of radon tests:

Active tests require special equipment and are generally the most accurate, but they require a specially trained technician.

Passive tests include myriad inexpensive testing products available at hardware stores, DIY home centers, or by Internet and mail -- all from state-certified testing labs. These devices are exposed to the air inside the basement for a specified length of time; then they are mailed to a testing laboratory. Long-term passive tests offer a good indication of the year-round average radon exposure but must be in place for at least 90 days. Short-term tests, though not as accurate, can be completed in as little as 48 hours. Short-term testing is normally done under closed-house conditions. That means keeping all windows and doors closed (except for normal entry and exit) and refraining from using fans or other machines that bring outside air into the house. The home’s heating system may be operated normally while the test is being performed, but the cooling system can be used only if it does not draw outside air into the house. A short-term test indicates closely enough whether or not a major problem exists. However, if a short-term test indicates that there is a problem, it’s recommended that another test be conducted to con firm the diagnosis.

If testing indicates a level of radon of more than 4 picocuries per liter (pCi/L) of air (a standard measurement of radon), take steps to reduce the radon by employing a process called mitigation. A level of about 1.3 (pCi/L) is considered average and generally not worth the expense of mitigation.

Minimize Radon -- Sealing cracks and other openings in the foundation approaches. However, the EPA does not recommend sealing alone because it has not been proven effective. In most cases, reduction systems that incorporate pipes and fans to vent air to the outdoors are preferred. Contact a licensed mitigation specialist.


Asbestos is a fibrous mineral found in rocks and soil throughout the world. Alone or in combination with other materials, asbestos was once fashioned into a variety of building materials because It’s strong, durable, fire retardant, and an efficient insulator. Unfortunately, it also is a carcinogen. Once inhaled, asbestos fibers lodge in the lungs. Because the material is so durable, it remains in the lung tissue and becomes concentrated as repeated exposure occurs over time. Asbestos can cause cancer of the lungs and stomach among those who have pro longed work-related exposure to it. Home health risks arise when age, accidental damage, normal cleaning, or remodeling activities cause the asbestos-containing materials to crumble, flake, or deteriorate. The health effects of low exposures to asbestos are uncertain, but experts can’t provide assurances that even a small level of exposure is completely safe.

According to the EPA, houses constructed in the United States during the last 20 years are less likely to contain asbestos products than houses built earlier. Asbestos some times is found around pipes and furnaces, and in older products: some vinyl flooring materials, ceiling tiles, exterior roofing, and some wallboards. It also was mixed with other materials and troweled or sprayed around pipes, ducts, and beams.

Warning: If you think asbestos has been used in your basement, have the area inspected by a professional before remodeling. Never attempt to remove asbestos yourself. The materials must be removed and disposed of according to strict guidelines. This is a job for trained specialists only. You will find these experts in the phone book or Internet under Asbestos Removal and Abatement.
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Updated: Wednesday, February 2, 2022 11:15