33 C.F.R. § 157.10c
(a) This section applies to each tankship of 20,000 DWT or more, but less then 40,000 DWT, except each one that—
(4) Has undergone a major conversion, for which—
(b) On January 1, 1986, or 15 years after the date it was delivered to the original owner or 15 years after the completion of a major conversion, whichever is later, a vessel under this section that carries crude oil must have—
(c) On January 1, 1986, or 15 years after the date it was delivered to the original owner or 15 years after the completion of a major conversion, whichever is later, a vessel under this section that carries product must have—
(d) If the arrangement of tanks on a vessel under this section is such that, when using the tankage necessary to comply with the draft and trim requirements in § 157.09(b), the draft amidships exceeds the minimum required draft by more the 10 percent, or the arrangement results in the propeller being fully immersed by more than 10 percent of its diameter, alternative arrangements may be accepted provided—
[CGD 82-28, 50 FR 11626, Mar. 22, 1985; 50 FR 12800, Apr. 1, 1985]