(a) After loading but before departure, and at other times necessary to assure the safety of the vessel, the master shall verify that the vessel complies with requirements in its trim-and-stability book, stability letter, Certificate of Inspection, and Loadline Certificate, whichever apply, and then enter a statement of the verification in the log book. The vessel may not leave port until it is in compliance with these requirements.
(b) When determining compliance with applicable stability requirements, the master shall ascertain the vessel's draft, trim, and stability as necessary; and any stability calculations made in support of the determination must remain aboard the vessel for the duration of the voyage.