Definitions.

§ 81.1 Definitions. As used in this part: 72 COLREGS refers to the International Regulations for Preventing Collisions at Sea, 1972, done at London, October 20, 1972, as rectified by the Proces-Verbal of December 1, 1973, as amended. A vessel of special construction or purpose means a vessel designed or modified to perform a special function and whose arrangement is thereby made relatively inflexible. Interference with the special function of the vessel occurs when installation or use of lights, shapes, or sound-signaling appliances under 72 COLREGS prevents or significantly hinders the operation in which the vessel is usually engaged. [CGD 77–136, 47 FR 13799, Apr. 1, 1982]