Radon in BuildingsDr. Rajiv R. Sahay, CIAQP, FIAS, EDLab Lab Director

Radon at-a-glance

It is a radioactive gas and can have a big impact on indoor air quality. It is a colorless, toxic gas that can be condensed to a transparent liquid and to an opaque, glowing solid. Radiation from natural radionuclides in rocks and soil; radioactive substances in our diet; in the air which we breathe; etc. are common in human environments. However, radon is mainly derived from the radioactive decay of radium.

Source of Radon

The main source of radon is the decaying product of radium (Ra88 isotopes Ra-226 and 222), the isotope Ra-226 is the result of the long decay of Uranium-238 (U92, isotopes U-233 to 238). It is present in almost all rocks, soils and water. In indoor environments/air, it typically comes from soil, building materials, tap water, and domestic gas as well as outside air. Byproducts such as gypsum, alum shale, and volcanic tuffs, etc. are identified as some of those products used in building construction.

Radon AnalysisRadon concentration

The concentration in indoor environment/air depends on the surrounding weather, soil, moisture, and porosity of the closed structure. In some cases, elevated indoor radon levels may arise due to the use of building materials. Levels in soil varies from a few hundred to several thousands of Picocuries per liter (pCi/L). The average indoor radon level in the United States is about 1.3 pCi/L in air as per the national residential radon survey completed in 1991. The outdoor concentration is approximately 0.4pCi/L. Almost similar findings are reported by The United Nation Scientific Committee on the Effects of Atomic Radiations (UNSCEAR) for a “typical” house on the ground floor.

Health implications

Approximately 21,000 lung cancer deaths each year in the United States are reported due to radon in indoor air as per the EPA assessment of Risk from Radon (EPA 402-R-003, June 2003). However, immediate symptoms from exposure to radon is not defined. Both World Health Organization (WHO) and EPA listed this substance as carcinogenic. Adverse health effects arose due to inhalation exposure. It is estimated that usually lung cancer would occur with 5-25 years of exposure. Exposure of radon is not linked with respiratory diseases or aliments. It is believed that smokers are at greater risk of developing radon-induced lung cancer.

A simple do-it-yourself screen test is available to check radon in buildings; however, a detailed professional assessment may be warranted to confirm the level of radon in occupied spaces and/or other indoor air pollutants.

About Pure Air Control Services
Pure Air Control Services, Inc. was established in 1984 as a small, mechanical, contracting firm and has since set the industry standard for indoor environmental quality diagnosis, environmental laboratory and remediation. Pure Air Control Services has serviced more than 600 million square feet of indoor environments in over 10,000 facilities.

Pure Air’s nationally performed services include: Building Sciences Evaluation; Building Health Check; a CDC ELITE Environmental Microbiology Laboratory; Environmental Project Management; HVAC New Life Restoration and PURE-Steam Coil Cleaning/Mold Remediation Services, among other indoor environmental services.

About Environmental Diagnostics Laboratory (EDLab)
The Environmental Diagnostics Laboratory (EDLab) (established in 1992) at Pure Air Control Services (PACS) is an environmental lab offering complete and comprehensive indoor environmental microbiology laboratory services. They include: microbiology, aerobiology, chemistry, allergen assays and microscopy designed to meet all your indoor air needs. EDLab supports IAQ investigations by assisting with strategic sampling plan development and supplying media collection equipment while performing a wide range of environmental analyses.

For more information on EDLab at Pure Air Control Services, Inc. please contact Dr. Rajiv Sahay, CIAQP, FIAS, at (800) 422-7873 x 304, or visit www.edlab.org.