5 C.F.R. § 352.502
Coverage
This subpart applies to any of the following serving in a position in the Federal Government:
(a) A person serving in the competitive service under a career or career-conditional appointment.
(b) A person serving under a career appointment in the Senior Executive Service (SES).
(c) A person serving in the excepted service under an appointment without a specific time limitation.
(d) A person appointed or assigned under authority of the Foreign Service Act of 1946, as amended (22 U.S.C. 801 et seq.).