5 C.F.R. § 9701.505 – Coverage.

(a) Employees covered. This subpart applies to eligible DHS employees, subject to a determination by the Secretary or designee under § 9701.102(b), except as provided in paragraph (b) of this section. DHS employees who would otherwise be covered by 5 U.S.C. chapter 71 are eligible for coverage under this subpart. In addition, this subpart applies to an employee whose employment has ceased because of an unfair labor practice under § 9701.517 of this subpart and who has not obtained any other regular and substantially equivalent employment.
(b) Employees excluded. This subpart does not apply to—
1. (1) An alien or noncitizen of the United States who occupies a position outside the United States;
2. (2) A member of the uniformed services as defined in 5 U.S.C. 2101(3);
3. (3) A supervisor or a management official;
4. (4) Any person who participates in a strike in violation of 5 U.S.C. 7311;
5. (5) Employees of the United States Secret Service, including the United States Secret Service Uniformed Division;
6. (6) Employees of the Transportation Security Administration; or
7. (7) Any employee excluded pursuant to § 9701.514 or any other legal authority.