22 U.S.C. § 4028a

1. (a)
   1. (1)Except as provided in paragraph (2), any newly hired Foreign Service employee who is in initial orientation training, or any other training expected to last less than 6 months in the Washington, D.C. area before transferring to the employee’s first assignment overseas or domestically outside the Washington, D.C. area shall, for the duration of such training, receive a per diem allowance at the levels prescribed under subchapter I of chapter 57 of title 5.
   2. (2)A newly hired Foreign Service employee may not receive any lodging expenses under the applicable per diem allowance pursuant to paragraph (1) if that employee—
      1. (A)has a permanent residence in the Washington, D.C., area (not including government-supplied housing during such orientation training or other training); and
      2. (B)does not vacate such residence during such orientation training or other training.
2. (b)In this section—
   1. (1)the term “per diem allowance” has the meaning given such term in section 5701 of title 5; and
   2. (2)the term “Washington, D.C., area” means the geographic area within a 50-mile radius of the Washington Monument.