December 12th, 2017
The City of East Moline, (Rock Island County) Illinois is located in an Environmental ProtectionAgency (EPA) radon Zone 1. The Illinois Department of Nuclear Safety's random survey of homes in the county indicated that >50% of the homes tested had radon levels above the EPA action guideline of 4 picoCuries/liter (pCi/L). The City Health Department began a voluntary program for construction of new, single-family homes using passive Radon-Resistant New Construction (RRNC) in June 1994. The City Health Department convinced the City Council to provide instructional materials and to reduce the cost of the building permit as incentives to sign up contractors in the program. As of September 1997, eleven contractors have used modified EPA model standards to incorporate passive RRNC into 124 new homes around the City. Forty-six of these homes have been tested for indoor radon levels after occupancy. Twenty-seven of the homes were below the 4 pCi/L USEPA action guideline for radon in indoor air. The City and homeowners of the 19 homes with radon levels above the guideline are experimenting with passive enhancement strategies to lower the existing radon levels. To strengthen the argument in favor of a change in the City building codes, the City Health Department undertook a sampling of the passive systems both in-place and deactivated by capping to evaluate the effectiveness of the passive system in reducing indoor radon levels in twenty-three homes. Radon was sampled in the air of the lowest level of the home suitable for occupancy with the system operational, in the air of that level after the system was deactivated, and inside the stack. To evaluate whether passive RRNC might also impact other indicators of poor indoor air quality, bioaerosols were sampled in the stack and in the air of four homes with the systems operational. The study was possible due to the cooperation of the homeowners, an EPA Region V assistance grant, and research assistance from the Environmental Health Program at Illinois State University. The City recently adopted the modified EPA model standards and techniques for mandatory control of radon in new residential buildings. The results of the research will be shared in the paper presented.