# 40 C.F.R. § 61.101 (2026): Definitions

> Federal · Regulations · In force

URL: https://www.frixlaw.com/law-library/statutes/CFR_T40_P61_S61_101

## Section

- **Citation:** 40 C.F.R. § 61.101 (2026)
- **Heading:** Definitions
- **Jurisdiction:** Federal
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** August 14, 2026
- **Source:** Compiled text
- **Location:** Title 40 CFR: Protection of Environment / Chapter I / Part 61 / Subpart I / § 61.101: § 61.101   Definitions.

## Text

As used in this subpart, all terms not defined here have the meaning given them in the Clean Air Act or subpart A of part 61. The following terms shall have the following specific meanings: (a) Effective dose equivalent means the sum of the products of absorbed dose and appropriate factors to account for differences in biological effectiveness due to the quality of radiation and its distribution in the body of reference man. The unit of the effective dose equivalent is the rem. For purposes of this subpart doses caused by radon-222 and its decay products formed after the radon is released from the facility are not included. The method for calculating effective dose equivalent and the definition of reference man are outlined in the International Commission on Radiological Protection's Publication No. 26. (b) Facility means all buildings, structures and operations on one contiguous site. (c) Federal facility means any facility owned or operated by any department, commission, agency, office, bureau or other unit of the government of the United States of America except for facilities owned or operated by the Department of Energy. (d) Radionuclide means a type of atom which spontaneously undergoes radioactive decay. [54 FR 51697, Dec. 15, 1989, as amended at 61 FR 68981, Dec. 30, 1996]

## Nearby sections

- [40 C.F.R. § 61.100 (2026) § 61.100   Applicability.](https://www.frixlaw.com/law-library/statutes/CFR_T40_P61_S61_100.md)
- [40 C.F.R. § 61.101 (2026) § 61.101   Definitions.](https://www.frixlaw.com/law-library/statutes/CFR_T40_P61_S61_101.md)
- [40 C.F.R. § 61.102 (2026) § 61.102   Standard.](https://www.frixlaw.com/law-library/statutes/CFR_T40_P61_S61_102.md)
- [40 C.F.R. § 61.103 (2026) § 61.103   Determining compliance.](https://www.frixlaw.com/law-library/statutes/CFR_T40_P61_S61_103.md)
- [40 C.F.R. § 61.104 (2026) § 61.104   Reporting requirements.](https://www.frixlaw.com/law-library/statutes/CFR_T40_P61_S61_104.md)
- [40 C.F.R. § 61.105 (2026) § 61.105   Recordkeeping requirements.](https://www.frixlaw.com/law-library/statutes/CFR_T40_P61_S61_105.md)
- [40 C.F.R. § 61.106 (2026) § 61.106   Applications to construct or modify.](https://www.frixlaw.com/law-library/statutes/CFR_T40_P61_S61_106.md)
- [40 C.F.R. § 61.107 (2026) § 61.107   Emission determination.](https://www.frixlaw.com/law-library/statutes/CFR_T40_P61_S61_107.md)
- [40 C.F.R. § 61.108 (2026) § 61.108   Exemption from the reporting and testing requirements of 40 CFR 61.10.](https://www.frixlaw.com/law-library/statutes/CFR_T40_P61_S61_108.md)

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/CFR_T40_P61_S61_101. Check the current official text before relying on it. Not legal advice.