In this subpart—

Agency head means the Secretary of Energy. For purposes of this subpart, agency head is also deemed to include the designated representative of the Secretary of Energy, except that the designated representative must be a department headquarters-level official who reports directly to the Secretary of Energy, or to the Deputy Secretary of Energy, and who is the sole such representative for the entire department.

Nuclear materials courier means an employee of the Department of Energy, the duties of whose position are primarily to transport, and provide armed escort and protection during transit of, nuclear weapons, nuclear weapon components, strategic quantities of special nuclear materials or other materials related to national security, including an employee engaged in this activity who is transferred directly to a supervisory or administrative position within the same Department of Energy organization, after performing this activity for at least 3 years. (See 5 U.S.C. 8331(27).)

Primary duties are those duties of a position that—

Are paramount in influence or weight; that is, constitute the basic reasons for the existence of the position;

Occupy a substantial portion of the individual's working time over a typical work cycle; and

Are assigned on a regular and recurring basis.

Duties that are of an emergency, incidental, or temporary nature cannot be considered primary even if they meet the substantial portion of time criterion. In general, if an employee spends an average of at least 50 percent of his or her time performing a duty or group of duties, they are his or her primary duties.

Primary position means a position that is in an organization of the Department of Energy and whose primary duties are to transport, and provide armed escort and protection during transit of, nuclear weapons, nuclear weapon components, strategic quantities of special nuclear materials or other materials related to national security.

Secondary position means a position that:

Is clearly in the nuclear materials transportation field;

Is in an organization of the Department of Energy having a nuclear materials transportation mission; and

Is either—

Supervisory; i.e., a position whose primary duties are as a first-level supervisor of nuclear materials couriers in primary positions; or

Administrative; i.e., an executive, managerial, technical, semiprofessional, or professional position for which experience in a primary nuclear materials courier position is a prerequisite.