(a) The provisions of this subpart, with the exception of Sec. 190.15-90, shall apply to all vessels other than non-self- propelled vessels of less than 300 gross tons, contracted for on or after March 1, 1968.
(b) Vessels contracted for prior to March 1, 1968, shall meet the requirements of Sec. 190.15-90.
(c) Non-self-propelled vessels of less than 300 gross tons shall not be subject to the provisions of this subpart.