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Recommended Residential Radon Mitigation Standard of Practice

EPA recommends the ASTM E2121-09 Standard Practice for Radon Mitigation Systems in Existing Low-Rise Residential Buildings* for residential radon mitigation. The Agency initially recognized this standard in 2003 as the most appropriate guide to reducing radon in homes as far as practicable below the national action level of 4 pCi/L in indoor air.

A single free printed copy of ASTM E 2121-09 is available from EPA upon request. Use EPA’s document number (402-K-07-007) when ordering from the National Service Center for Environmental Publications. *ASTM E2121-09; November 9, 2009. EPA reprints E2121-09 with permission from ASTM. Copies of E2121-09 may be purchased from ASTM International exiting EPA, or from the American National Standards Institute exiting EPA.

*American Society for Testing and Materials International, or ASTMI; an American National Standards Institute, or ANSI, approved consensus standard. Note: As of May 2006, EPA's Radon Mitigation Standards (EPA 402-R-93-078, Revised April 1994) is no longer recommended or available.

Additional Resources

Additional Indoor Air Quality resources on Asthma, Secondhand Smoke, Schools, Large Buildings and Homes can be found at our Indoor Air Publications site.

Health Risks Hotlines Indoor airPLUS Kids, Students & Teachers Map of Radon Zones Media Campaigns Radon Action Month Radon-Resistant New Construction Radon and Real Estate Radon and Drinking Water Radon Leaders Saving Lives State Contacts SIRG Test & Fix Your Home Webinars Indoor Air Quality

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