41 CFR § 301-11.20 - May my agency authorize a rest period for me while I am traveling?
(a) Your agency may authorize a rest period not in excess of 24 hours at either an intermediate point or at your destination when:
(1) Either your origin or destination is OCONUS;
(2) Your scheduled flight time, including stopovers, exceeds 14 hours;
(3) Travel is by a direct or usually traveled route; and
(4) Travel is by coach class or premium economy class.
(b) When a rest stop is authorized the applicable per diem rate is the rate for the rest stop location.
(c) Your agency may authorize a rest period that exceeds 24 hours when no scheduled transportation service departs within 24 hours of your arrival at an intermediate point. To qualify for a rest period exceeding 24 hours, you must be scheduled to board the first available scheduled departure. Your agency will determine a reasonable additional length of time for any rest period exceeding 24 hours.