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

Subpart I: National Emission Standards for Radionuclide Emissions From Federal Facilities Other Than Nuclear Regulatory Commission Licensees and Not Covered by Subpart H
Basic Information
Legal Authorities
  • 42 U.S.C. §7401
Federal Register Citations
  • 54 FR 51697
Code of Federal Regulations Citations
  • 40 CFR Part 61
Effective Date
  • December 15, 1989

On this page:

  • Rule Summary
  • Rule History
  • Additional Resources
  • Compliance

Rule Summary

Subpart I protects the public and the environment from radionuclideRadioactive 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 airThe air that surrounds us based on two criteria:

  1. Emissions of radionuclides, including iodine, to the ambient air from a facility regulated under this subpart shall not exceed those amounts that would cause any member of the public to receive in any year an effective 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  10 milliremThe millirem is the U.S. unit used to measure effective dose. One millirem equals 0.001 rem. The international unit is milliSievert (mSv). (0.1 millisievert).
  2. Emissions of iodine to the ambient air from a facility regulated under this subpart shall not exceed those amounts that would cause any member of the public to receive in any year an EDE of 3 millirem (0.03 millisievert).

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

  • DOE facilities (see Subpart H).
  • Nuclear Regulatory Commission licensees (subject to NRC's regulatory program).
  • Disposal activities that are subject to 40 CFR Part 191 Subpart B.
  • Low-energy accelerators.
  • Uranium mill tailingsThe remaining portion of a metal-bearing ore after some or all of a metal, such as uranium, has been extracted. piles disposed of under 40 CFR Part 192.

Rule History

When Subpart I was promulgated, it applied to facilities regulated by the Nuclear Regulatory Commission (NRC) and NRC Agreement States. The applicability of Subpart I to NRC licensees was stayed, and eventually rescinded. 

For complete information see the December 30, 1996 Federal Register notice regarding the rescission of 40 CFR Part 61, Subpart I (pdf) (156.47 KB).

Additional Resources

For supporting documents see, Subpart I: Resources.

Compliance

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.

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Last updated on May 8, 2025
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