46 C.F.R. § 90.10-11 Coastwise.
Title 46 - Shipping
Under this designation shall be included all vessels normally navigating the waters of any ocean or the Gulf of Mexico 20 nautical miles or less offshore.
Title 46: Shipping
PART 90—GENERAL PROVISIONS
Subpart 90.10—Definition of Terms Used in This Subchapter
§ 90.10-11 Coastwise.