§ 5925. Post differentials
(a)
A post differential may be granted on the basis of conditions of environment which differ substantially from conditions of environment in the continental United States and warrant additional pay as a recruitment and retention incentive. A post differential may be granted to an employee officially stationed in the United States who is on extended detail in a foreign area. A post differential under this subsection may not exceed 35 percent of the rate of basic pay.
(b)
Any employee granted a differential under subsection (a) of this section may be granted an additional differential for an assignment to a post determined to have especially adverse conditions of environment which warrant additional pay as a recruitment and retention incentive for the filling of positions at that post. An additional differential for any employee under this subsection—