Radiation Protection

Subpart I: National Emission Standards for Radionuclide Emissions From Federal Facilities Other Than Nuclear Regulatory Commission Licensees and Not Covered by Subpart H

Rule Summary

Subpart I protects the public and the environment from radionuclideHelpradionuclideRadioactive forms of elements are called radionuclides. Radium-226, Cesium-137, and Strontium-90 are examples of radionuclides. emissions emitted by federal facilities that are not regulated elsewhere. Subpart I limits radionuclide emissions to the ambient airHelpambient airThe air that surrounds us based on two criteria:

  1. The annual 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) to any individual must not exceed 10 milliremHelpmilliremThe millirem is the U.S. unit used to measure effective dose. One millirem equals 0.001 rem. The international unit is milliSievert (mSv). (mrem).
  2. The annual ede from radioiodine must not exceed 3 mrem.

Federal facilities emissions to which Subpart I does NOT apply include the following:

Rule History

View the December 30, 1996 Federal Register notice regarding the rescission of 40 CFR Part 61, Subpart I (PDF)(10 pp, 156.47 K, About PDF).

Additional Resources

For supporting documents see, Subpart I: Resources.


Owners or operators of these facilities must use the COMPLY computer model to calculate effective dose equivalent (ede) or obtain approval from EPA to use other models. They are required to submit annual reports to EPA on emissions and obtain EPA's approval  for some types of construction. 

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