This subpart prescribes the requirements for measuring a vessel in order to comply with the International Convention on Tonnage Measurement of Ships, 1969 (Convention), and 46 U.S.C. chapter 143.

As used in this subpart—

Amidships means the midpoint of the registered length, as “registered length” is defined in this section.

Boundary bulkhead means the bulkhead or partition that separates an enclosed interior space from the surrounding weather. In general, the exterior bulkhead of a deck structure is the boundary bulkhead.

Cargo space means an enclosed space appropriated for the transport of cargo which is to be discharged from the vessel. The term does not include a space which qualifies as an excluded space under § 69.61.

Enclosed space is defined in § 69.59.

Excluded space is defined in § 69.61.

Line of the upper deck means a longitudinal line at the underside of the upper deck or, if that deck is stepped, the longitudinal line of the underside of the lowest portion of that deck parallel with the upper portions of that deck.

Molded depth means the vertical distance amidships between the following points:

(a) From the line of the upper deck at the vessel's side or, if the vessel has rounded gunwales, from the intersection of the line of the upper deck extended to the molded line of the shell plating as though the gunwales were of angular design.

(b) To the top of the flat keel, to the lower edge of the keel rabbet if the vessel is of wood or composite structure, or to the point where the line of the flat of the bottom extended inward cuts the side of the keel if the vessel's lower part is hollow or has thick garboards.

Molded draft means—

(a) For vessels assigned a load line under parts 42, 44, 45, or 47 of this chapter, the draft corresponding to the Summer Load Line (other than a timber load line);

(b) For passenger vessels assigned a load line under part 46 of this chapter, the draft corresponding to the deepest subdivision load line assigned;

(c) For vessels to which parts 42, 44, 45, 46, or 47 of this chapter do not apply but which otherwise have been assigned a load line, the draft corresponding to the Summer Load Line so assigned;

(d) For vessels to which no load line has been assigned but the draft of which is restricted under any Coast Guard requirement, the maximum draft permitted under the restriction; and

(e) For other vessels, 75 per cent of the molded depth.

Passenger means a person on board a vessel other than—

(a) The master, a member of the crew, or other person employed or engaged in any capacity in the business of the vessel; and

(b) A child under one year of age.

Registered breadth means the maximum breadth of a vessel measured amidships to the molded line of the frame in a vessel with a metal shell and to the outer surface of the hull in all other vessels.

Registered length means either 96 percent of the length on a waterline at 85 percent of the least molded depth measured from the top of the flat keel or the length from the fore side of the stem to the axis of the rudder stock on that waterline, whichever is greater. In vessels designed with a rake of keel, this length is measured on a waterline parallel to the design waterline.

Upper deck means the uppermost complete deck exposed to weather and sea, which has permanent means of weathertight closing of all openings in the weather part of the deck, and below which all openings in the sides of the vessel are fitted with permanent means of watertight closing.

Weathertight means secure against penetration of water into the vessel in any sea condition.

Applications for measurement under this subpart must include the following information and plans:

(a) Type of vessel.

(b) Vessel's name and official number (if assigned).

(c) Builder's name and the vessel hull number assigned by builder.

(d) Place built and delivery date (or scheduled delivery date).

(e) Date keel was laid.

(f) Overall length, breadth, and depth of vessel.

(g) Lines plan.

(h) Booklet of offsets at stations.

(i) Capacity plans for tanks and cargo compartments.

(j) Hydrostatic curves.

(k) Construction plans showing measurements and scantlings of deck structures, hatches, appendages, recesses, and other enclosed spaces.

(l) Arrangement plans.

Gross tonnage ITC (GT ITC) is determined by the following formula GT ITC = K1 V, in which V = total volume of all enclosed spaces in cubic meters and K1 = 0.2 + 0.02 log10 V.

Enclosed space means a space which is bounded by the vessel's hull, by fixed or portable partitions or bulkheads, or by decks or coverings other than permanent or movable awnings. No break in a deck, nor any opening in the vessel's hull, in a deck or in a covering of a space, or in the partitions or bulkheads of a space, nor the absence of a partition or bulkhead precludes the space from being included in the enclosed space. Portable enclosed spaces, regardless of method of attachment to the vessel, are treated as enclosed spaces as defined in this paragraph.

(a) Excluded space means an enclosed space which is excluded from the total volume of all enclosed spaces (V) in calculating gross tonnage ITC. Spaces that are below the upper deck and open to the sea, as well as those spaces listed in paragraphs (b) through (f) of this section, are excluded spaces, except as under paragraph (g) of this section.

(b) A space that is within a structure and that is opposite an end opening extending from deck to deck (except for a curtain plate of a height not exceeding by more than one inch the depth of the adjoining deck beams) and having a breadth equal to or greater than 90 percent of the breadth of the deck at the line of the opening is an excluded space, subject to the following:

(1) Only the space between the actual end opening and a line drawn parallel to the line or face of the opening at a distance from the opening equal to one-half of the breadth of the deck at the line of the opening is excluded. (See § 69.75, figure 1.)

(2) If, because of any arrangement (except convergence of the outside plating as shown in § 69.75, figure 3), the breadth of the space is less than 90 percent of the breadth of the deck, only the space between the line of the opening and a parallel line drawn through the point where the athwartship breadth of the space is equal to 90 percent or less of the breadth of the deck is excluded. (See § 69.75, figures 2 and 4.)

(3) When any two spaces, either of which is excluded under paragraphs (b)(1) or (b)(2) of this section, are separated by an area that is completely open except for bulwarks or open rails, these two spaces must not be excluded if the separation between the two spaces is less than the least half breadth of the deck in way of the separation. (See § 69.75, figures 5 and 6.)

(4) When the deck at the line of an opening has rounded gunwales, the breadth of the deck is the distance between the tangent points indicated in § 69.75, figure 11.

(c) A space that is open to the weather and that is under an overhead deck covering with no connection on the space's exposed sides between the covering and the deck other than the stanchions necessary for the covering's support is an excluded space. An open rail or bulwark fitted at the vessel's side does not disqualify the space from being an excluded space if the height between the top of the rail or bulwark and the overhead structure or curtain plate (if fitted) is not less than 2.5 feet or one-third of the height of the space, whichever is greater. (See § 69.75, figure 7.)

(d) A space in a side-to-side structure directly in way of opposite side openings not less than 2.5 feet in height or one-third of the height of the structure, whichever is greater, is an excluded space. If the opening is only on one side of the structure, the space to be excluded is limited inboard from the opening to a maximum of one-half of the breadth of the deck in way of the opening. (See § 69.75, figure 8.)

(e) A space in a structure immediately below an uncovered opening in the deck overhead is an excluded space, if the opening is exposed to the weather and the space to be excluded is limited to the area of the opening. (See § 69.75, figure 9.)

(f) A recess in the boundary bulkhead of a structure which is exposed to the weather and which has an opening that extends from deck to deck without a means of closing is an excluded space, if the interior width of the space is not greater than the width of the opening and extension of the space into the structure is not greater than twice the width of the opening. (See § 69.75, figure 10.)

(g) Any space described in paragraphs (a) through (f) of this section which fulfills at least one of the following conditions is not an excluded space:

(1) The space is fitted with shelves or other means designed for securing cargo or stores.

(2) The opening that would otherwise permit the space to be excluded space is fitted with a means of closure.

(3) Other features of the space make it possible for the space to be closed.

Net tonnage ITC (NT ITC) is determined by the formula:

(a) Volumes V and Vc used in calculating gross tonnage ITC and net tonnage ITC, respectively, must be measured and calculated according to accepted naval architectural practices for the spaces concerned.

(b) Measurements must be taken, regardless of the fitting of insulation or the like, to the inner side of the shell or structural boundary plating in vessels constructed of metal, and to the outer surface of the shell or to the inner side of structural boundary surfaces in all other vessels.

Cargo spaces used in determining volume (Vc) for calculating net tonnage must be permanently marked with the letters “CC” (cargo compartment) which are at least four inches in height and positioned so as to be visible at all times.

(a) On request of the vessel owner, the authorized measurement organization must issue an International Tonnage Certificate (1969) as evidence of the vessel's measurement under this subpart for a vessel that is 24 meters (79.0 feet) or more in registered length, will engage on a foreign voyage, and is not a vessel of war. The Certificate is delivered to the vessel owner or master and must be maintained on board the vessel when it is engaged on a foreign voyage. For a vessel for which a remeasurement under § 69.71 resulted in a net tonnage ITC decrease due to changes other than alterations or modifications to the vessel deemed by the Commandant to be of a major character, an International Tonnage Certificate (1969) reflecting the decreased net tonnage ITC will not be reissued until 12 months have elapsed from the date of measurement indicated on the current certificate.

(b) If an International Tonnage Certificate (1969) is not issued for a vessel measured under this part, the measurement organization must issue a U.S. Tonnage Certificate as evidence of the vessel's measurement under this subpart, which must also indicate the vessel's measurement under any other subpart of this part. There is no requirement to maintain the U.S. Tonnage Certificate on board the vessel.

(c) For a vessel that transfers flag to a foreign country that is party to the Convention, the International Tonnage Certificate (1969) remains valid for a period not to exceed 3 months after the flag transfer, or until an International Tonnage Certificate (1969) is issued under authority of the foreign country to replace it, whichever is earlier.

(a) When a vessel is altered so that the net tonnage is increased, the new net tonnage must be applied immediately.

(b) A vessel concurrently assigned load lines under both the International Convention on Load Lines and either the International Convention for the Safety of Life at Sea (SOLAS) or other international agreement must be assigned only one net tonnage. The net tonnage assigned must be the net tonnage applicable to the load line assigned under the International Convention on Load Lines, SOLAS or other international agreement for the trade in which the vessel in engaged.

(c) When a vessel is altered so that the net tonnage is decreased or the vessel's trade is changed so that the load line assigned for that trade under paragraph (b) of this section is no longer appropriate and results in a decrease in its net tonnage, a new International Tonnage Certificate (1969) incorporating that net tonnage may not be issued until twelve months after the date on which the current Certificate was issued. However, if one of the following apply, a new Certificate may be issued immediately:

(1) The vessel is transferred to the flag of another nation.

(2) The vessel undergoes alterations or modifications which the Commandant deems to be of a major character, such as the removal of a superstructure which requires an alteration of the assigned load line.

(a) When application of this subpart to a novel type vessel produces unreasonable or impractical results, the Commandant may determine a more suitable method of measurement.

(b) Requests for a determination must be submitted to the Commandant, explaining the reasons for seeking a determination, and including a description of the spaces in question, if applicable.