5 CFR §630.305

Before annual leave may be restored under 5 U.S.C. 6304, the determination that an exigency is of major importance and that therefore annual leave may not be used by employees to avoid forfeiture must be made by the head of the agency or someone designated to act for him or her on this matter. Except where made by the head of the agency, the determination may not be made by any official whose leave would be affected by the decision.