5 CFR §831.804

1. (a)An employee's service in a position that has been determined by the Secretary of the Department of Energy to be a secondary nuclear materials courier position following 3 years of service in a primary nuclear materials courier position is covered under the provisions of 5 U.S.C. 8336(c) if all of the following criteria are met:
   1. (1)The employee is transferred directly (i.e., without a break in service exceeding 3 days) from a primary position to a secondary position; and
   2. (2)If applicable, the employee has been continuously employed in secondary positions since transferring from a primary position without a break in service exceeding 3 days, except that a break in employment in secondary positions which begins with an involuntary separation (not for cause), within the meaning of 5 U.S.C. 8336(d)(1), is not considered in determining whether the service in secondary positions is continuous for this purpose.
2. (b)An employee who is not in a primary position, nor covered while in a secondary position, and who is detailed or temporarily promoted to a secondary position is not covered under the provisions of 5 U.S.C. 8336(c).