I was part of a joint state-academic-industry team that supported the legislative adoption of the statewide building code for radon control in all new homes in Minnesota. While this code requirement is unique in the U.S. (being statewide), it is far from perfect as illustrated in the news clip cited below and here is part of the reason why:
•The Minnesota code adopts Appendix F of the International Residential Code with modifications.
•Appendix F calls for passive soil depressurization which, if properly installed, reduces average radon entry by 50%.
One of the modifications in Minnesota's adoption is an allowance for builders to use active soil depressurization (with a fan); however, the Minnesota code gives no guidance or requirements on installing active soil depressurization and one of the results is that systems are improperly installed as illustrated in the following news clip. If you view the clip, note that the fan is mounted horizontally in the vent pipe which is contrary to all standards and guidelines. The irony of this situation is the builder was trying to do better than the minimum required by code with the end result that radon reduction is severely compromised.
I am an outspoken advocate for radon control systems in all new homes in North America but we need to do things right or we risk misleading the public to thinking they are being protected from radon when in fact they are not. We must have effective radon control in all new homes or we will continue to witness a growing number of homes with elevated indoor radon (today, we have over 7 million homes with indoor radon concentrations above EPA's threshold for action whereas 20 years ago we had less than 6 million).
I encourage you do everything you can to support effective radon control in all new homes. Take a moment to view the pro's and con's of the two current approaches to radon control in new construction by viewing: www.aarst.org/images/Comparison_Appendix_F_and_1465_07_15_08.pdf. Then, view: www.aarst.org/AARST_RRNC_Position_Paper.pdf Some of the more important elements in the latter link are:
•Greater radon risk reduction is achieved through active versus passive soil depressurization.
•Effective radon control systems must be installed by nationally certified or state licensed radon mitigation professionals (the two EPA recognized national certification bodies are the National Environmental Health Association National Radon Proficiency Program and the National Radon Safety Board).
•The only way to know if a radon control system is effective in a new home is effective requires testing according to EPA protocols by an independent third party such as a nationally certified or state licensed radon measurement professional.
Thank you for your consideration and your efforts to achieve healthy homes for all families!
Professor, University of Minnesota
Director, Midwest Universities Radon Consortium, www.cce.umn.edu/radon
President, American Association of Radon Scientists and Technologists, www.aarst.org
Chair, World Health Organization's International Radon Project's Mitigation and Prevention Working Group, www.who.int/ionizing_radiation/env/radon/en/
United States