14 CFR 437.57 - Operating area containment.
(a) During each permitted flight, a permittee must contain its reusable suborbital rocket's instantaneous impact point within an operating area determined in accordance with paragraph (b) and outside any exclusion area defined by the FAA in accordance with paragraph (c) of this section.
(b) An operating area -
(1) Must be large enough to contain each planned trajectory and all expected vehicle dispersions;
(3) May not contain or be adjacent to a densely populated area or large concentrations of members of the public; and
(4) May not contain or be adjacent to significant automobile traffic, railway traffic, or waterborne vessel traffic.
(c) The FAA may prohibit a reusable suborbital rocket's instantaneous impact point from traversing certain areas within an operating area by designating one or more areas as exclusion areas, if necessary to protect public health and safety, safety of property, or foreign policy or national security interests of the United States. An exclusion area may be confined to a specific phase of flight.