Security zone as used in this part, means all areas of land, water, or land and water, which are so designated by the Captain of the Port for such time as he deems necessary to prevent damage or injury to any vessel or waterfront facility, to safeguard ports, harbors, territories, or waters of the United States or to secure the observance of the rights and obligations of the United States.
Code of Federal Regulations
[EO 11249, 30 FR 13001, Oct. 13, 1965]