33 CFR §150.355

1. (a)Clearance by a manned deepwater port's person in charge of vessel operations is required before a vessel, other than a tanker or support vessel, enters the safety zone.
2. (b)The port's person in charge of vessel operations may clear a vessel under paragraph (a) of this section only if its entry into the safety zone would not:
   1. (1)Interfere with the purpose of the deepwater port;
   2. (2)Endanger the safety of life, property, or environment; or
   3. (3)Be prohibited by regulation.
3. (c)At an unmanned deepwater port, such as a submerged turret landing (STL) system, paragraphs (a) and (b) of this section apply once a tanker connects to the STL buoy.