Code of Federal Regulations Title 46. Shipping § 46.178.320 Intact stability requirements—non-sailing vessels

(1) Monohull vessels;  and

(2) Flush deck catamaran vessels which are not pontoon vessels and carry not more than 49 passengers.

(1) The vessel carries not more than 49 passengers and does not make international voyages;

(2) The vessel operates on Protected Waters only;

(3) The vessel is constructed with only one deck;

(4) The buoyant hull volume consists of two symmetric, fully enclosed hulls;

(5) The cross section of each hull is circular or of wall-sided construction without tumblehome, and constant for at least 90 percent of the length of the hull;

(6) The hulls contain no machinery or tanks;

(7) The portion of the deck accessible to passengers does not extend beyond—

(8) There is no deck more than 0.15 meters (6 inches) above any point on any of the buoyant hulls;

(9) The distance between the centerlines of the hulls is not less than 1.83 meters (6 feet);  and

(10) Each hull has a beam or diameter, as applicable, of not less than 0.61 meters (2 feet).

(1) Dispense with the requirements of the simplified stability proof test in §§ 178.330 or § 178.340 of this part when the vessel's stability can be adequately assessed by alternate means giving due consideration to each item that impacts a vessel's stability characteristics which include, but are not limited to, the form, arrangement, construction, number of decks, route, and operating restrictions of the vessel;  or

(2) Authorize a change in the requirements of the simplified stability proof test in either §§ 178.330 or 178.340 of this part, when necessary to adequately assess the vessel's stability.