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Radiation Protection

Subpart B: National Emission Standards for Radon Emissions From Underground Uranium Mines

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Rule Summary

Subpart B protects the public and the environment from radon-222 emissions to the  ambient airHelpambient airThe air that surrounds us from underground uranium mines. Emissions to the ambient air of radon-222 from underground uranium mines shall not exceed those amounts that would cause any member of the public to receive in any year an effective doseHelpeffective doseThe amount of radiation absorbed by an object or person, adjusted to account for the type of radiation received and the effect on particular organs. The unit used for effective dose is rem (U.S. unit) or sievert (Sv, the international unit). equivalent (EDE) of more than 10 millirems (0.1 millisievert).

Owners/operators of each mine must calculate the effective dose equivalent to any member of the public and report this information to EPA annually.


All sampling done during data collection must follow EPA-approved procedures. The computer model COMPLY-R is approved for calculating effective dose equivalents. (Please note that COMPLY-R is a version of COMPLY that includes radon gas emissions. COMPLY does NOT include radon emissions and should not be used for Subpart B calculations.)  Alternative sampling methods and dose models may be used with prior approval by EPA. 

Download COMPLY-R (ZIP)(73 K) .
View the COMPLY-R User's Guide: Revision 1.

All facilities subject to any NESHAP must meet 40 CFR Part 61, Subpart A: General Provisions.