46 CFR §178.310

1. (a)Except as provided in paragraph (c) of this section, each vessel must, in each condition of loading and operation, comply with the applicable requirements of—
   1. (1)Part 170 of this chapter, except subparts G and H; and
   2. (2)Part 171 of this chapter, subparts A and B.
2. (b)Sailing vessels must meet the appropriate requirements of § 171.055 or § 171.057 in subchapter S in this chapter while under sail, as well as the requirements of § 170.170 in subchapter S in this chapter while under bare poles (if an auxiliary sailing vessel as defined in § 170.055(a) of this chapter) and with storm sails set and trimmed flat (if a sailing vessel as defined in § 170.055(n) of this chapter).
3. (c)As an alternative to meeting the requirements of paragraphs (a) and (b) of this section, a vessel may demonstrate compliance with an appropriate standard set forth in either § 178.320 of this part for non-sailing vessels or § 178.325 of this part for monohull sailing vessels if all of the following criteria are satisfied:
   1. (1)The length is not more than 19.8 meters (65 feet) in length;
   2. (2)The vessel does not carry more than 12 passengers on an international voyage;
   3. (3)The vessel either does not have more than one deck above the bulkhead deck or, if without a bulkhead deck, does not have more than one deck above the deck from which freeboard is measured excluding a pilot house; and
   4. (4)The vessel's stability has not been questioned by the cognizant Officer in Charge, Marine Inspection (OCMI).
4. (d)In lieu of the requirements in paragraphs (a) through (c) of this section, a vessel may meet another stability standard approved by the Commanding Officer, Marine Safety Center.