(a) The provisions of this subpart, with the exception of Sec. 190.07-90, shall apply to all vessels of 4,000 gross tons and over carrying not more than 150 persons and contracted for on or after March 1, 1968.
(b) The provisions of this subpart, with the exception of Sec. 190.07-90, shall apply to all vessels of 300 gross tons and over, but less than 4,000 gross tons, carrying in excess of 16 persons in the scientific party but not more than 150 persons and contracted for on or after March 1, 1968.
(c) Vessels contracted for prior to March 1, 1968, shall meet the requirements of Sec. 190.07-90.
(d) Those vessels which carry more than 150 persons shall meet the requirements in Sec. Sec. 72.05-5 through 72.05-60 of Subchapter H (Passenger Vessels) of this chapter.