Mitigation methods radon

In order to focus on more of the basic research problems related to radon, a symposium was organized in conjunction with the 191th National Meeting of the American Chemical Society. This volume presents most of the reports given at that symposium. There are five major groups of reports occurrence, measurement methods, physical and chemical properties of radon and its decay products, health effects, and mitigation of radon levels. 

Operation of cooperative projects between the Environmental Protection Agency s Radon Action Program and the State s radon program. Such projects shall include the Home Evaluation Program, in which the Environmental Protection Agency evaluates homes and States demonstrate mitigation methods in these homes. To the maximum extent practicable, consistent with the objectives of the evaluation and demonstration, homes of low-income persons should be selected for evaluation and demonstration. 

Demonstration of radon mitigation methods in various types of structures and in various geographic settings and publication of findings. In the case of demonstration of such methods in homes, the Administrator should select homes of low-income persons, to the maximum extent practicable and consistent with the objectives of the demonstration. 

Payment of costs of demonstration of radon mitigation methods and technologies as approved by the Administrator, including State participation in the Environmental Protection Agency Home Evaluation Program. 

The demonstrated expertise of the applicant regarding radon measurement and mitigation methods and other radon-related issues. 

In theory, the application of radon barriers should be adequate to avoid elevated radon levels in houses. In practice, however, a backup radon mitigation system has been found essential for maintaining indoor radon concentrations below 4 pCi/L in most homes studied. In the recent radon-resistant residential construction projects conducted by U.S. EPA and/or private builders, several of the homes designed to be radon resistant have contained radon concentrations above 4 pCi/L. In each of those houses, a backup system consisting of an active (fan-assisted), or passive (wind-and-stack-effect-assisted), SSD system was installed at the time of construction. When mechanical barriers failed to adequately control radon, the soil depressurization methods were made operational. 

Due to difficulties often encountered in sealing subfloors and insulating pipes in crawlspace houses, which rarely have a poured floor slab, another radon-resistant alternative that can be applied after construction should be considered. This mitigation technique is a variation of the successful SSD methods used in basements. Polyethylene sheeting is often used as a moisture barrier applied directly over the soil in crawlspaces. The polyethylene sheeting can be used as a gastight barrier that forms a small-volume plenum above the soil where radon collects. A fan can be installed to pull the collected soil gas from under the sheeting and exhaust it outside the house. 

Publication of public information materials concerning radon health risks and methods of radon mitigation. 

Development and demonstration of methods of radon measurement and mitigation that take into account unique characteristics, if any, of nonresidential buildings housing child care facilities. 

The purpose of a regional radon training center is to develop information and provide training to Federal and State ofhcials, professional and private firms, and the public regarding the health risks posed by radon and demonstrated methods of radon measurement and mitigation. 

If elevated or potentially hazardous radon levels are detected, there are many mitigation measures that can be taken to reduce exposure. The exact methods used will depend on the level of the gas and the design of the building. Some techniques are directed toward preventing radon from entering a building in the first place. Others are designed to reduce, by ventilation, the concentration of radon once it s in a structure. 

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