The hatchways referred to are the ones out in the open or in open spaces on the upper deck to the hull and on closed-in deck erections. Hatchways on between decks and on the deck of open erections are not to be measured and included in the aggregate of hatchways from which the statutory deduction is to be made. The total hatchways on between decks and on the portion of the decks within closed-in erections on the upper deck to the hull are automatically included in the between-deck spaces and in the said erections by the process of measurement; and, of course, the hatchways on decks of open erections are not to be considered, serving as they do spaces not entering into the tonnage of the vessel.

§ 2.42

Record of exempted spaces.

The tonnage measurement of all spaces that the measurer has not included in the gross tonnage of the vessel must be recorded in detail on customs Form 1410, "Tonnage Admeasurement” which, when forwarded to the Bureau for examination and appropriate action must be accompanied by suitable plans or sketches drawn to scale, or a complete explanation for the proper consideration of the exemption of such spaces. [T.D. 66-57, 31 F.R. 4295, Mar. 11, 1966] § 2.43 Enclosed spaces exempted from inclusion in gross tonnage.

In addition to the spaces omitted from inclusion in gross tonnage under the provisions of § 2.80 on vessels measured in accordance with the provisions of §§ 2.80 through 2.100, the following closed-in spaces situated on or above the upper deck shall not be included in the gross tonnage provided they are reasonable in extent, adapted and used exclusively for the purposes outlined:

(a) Companions. Companions and booby-hatches serving as a protection for companionways (stairways or ladderways) leading to spaces below, whether such spaces are exempted or not. (See a, b, c and d in Figure 35 (§ 2.65).)

(b) Galleys. Spaces fitted with ranges or ovens (bakeries), without regard to the category of the persons they serve.

(c) Light and air. Spaces forming part of the propelling machinery space, or serving for the admission of light and air to such machinery shall be exempt under the heading of light and air. When no part of the propelling machin

ery extends below the upper deck, the space occupied by same is exemptible in its entirety together with such fuel bunkers as are located on or above the upper deck. Where fuel bunkers or tanks are located wholly or in part below the upper deck the space so occupied below the upper deck is not deductible.

(d) Light and air on small boats. (1) A house of reasonable size, into which the propelling machinery projects above the deck line, or a similar house used exclusively for light and air over such machinery on small boats is exempted, in its entirety, as light and air.

(2) A compartment of reasonable size, bulkheaded off and similarly used, located in a house serving other purposes is likewise so treated.

(3) When propelling machinery and/ or light and air space, not bulkheaded off, is in a house serving other purposes, the actual length and breadth of the engine plus 2 feet each side and each end for working space, if such space is available, projecting up into the house becomes the length and breadth of exempted light and air, exclusive of such part as may be decked over and available for other purposes.

(4) If bunks, galley, supplies, etc., are located in the hull abreast the engine and under a house open to same, as described in preceding paragraph, and the 2-foot allowance for working space on each side of the engine base overlaps working space at galley, or as the case may be, allow one-half the actual breadth on each side the engine, which breadths plus the actual engine breadth projecting up into the house becomes the permissible breadth of light and air exemption.

(e) Machinery spaces. (1) Spaces occupied by machinery other than propelling machinery.

(2) The spaces occupied by dredging machinery on the upper deck of dredging vessels which are not self propelled but which are required to be documented are to be exempted. No allowance is to be made for spaces occupied by such machinery below the upper deck.

(f) Skylights. Skylights and domes affording ventilation and light to the erection thereunder, except skylights over propelling machinery. None of the space below the covering deck of such erection shall be exempted from inclusion in tonnage unless an opening is left in the deck of the superstructure immediately under such skylight or dome to

give ventilation and light to spaces below such deck line. (See exempted skylight and a, b, c and d in Figure 36 (§ 2.65).) For the treatment of skylights over propelling machinery, see paragraph (c) of this section.

(g) Special exempted water-ballast spaces. (1) Any space other than the double-bottom space adapted only for water ballast, certified by the collector not to be available for the carriage of cargo (other than ballast water for use for underwater drilling, mining, and related purposes, including production), stores, supplies, or fuel, shall be deducted from the gross tonnage as measured to get gross register tonnage.

(2) Adaptation for water ballast consists of having the space or spaces properly constructed and tested as ballast tanks; that the pumps, pipes, etc., for filling and emptying such tanks must be of suitable dimensions, connected to the ballast system, and completely independent of the cargo, fuel oil, feed or domestic water pumping apparatus. Access shall be only through oval or circular manholes, whose greatest diameter must not exceed 2 feet in the watertight deck. Where a hatch exists over a space now to be used for the carriage of water ballast, plating shall be fitted and riveted or welded to form a watertight cover and a manhole as above described may be fitted in this cover plate. Such manholes, except when fitted on the weather deck, may be provided with a coaming not exceeding 6 inches in height. If these spaces are found being used for purposes other than water ballast, they are to be added to the gross tonnage of the vessel, and so included until such changes have been made as will definitely preclude their use for purposes other than for water ballast.

(3) No space will be deemed to be adapted only for water ballast unless the Bureau is satisfied that the primary purpose of the space is to afford a means of maintaining stability, trim, immersion, seakeeping1 capabilities, or strength conditions under varying conditions and requirements of the vessel's operation and that the space claimed for exemp

1The term "seakeeping" as used in this paragraph is defined as the ability of a vessel to maintain good behavior at its designed speed or at a speed as close as possible to its designed speed under all conditions of sea and weather which the vessel may encounter in its designated service.

tion is necessary to and available at all times for any one of these purposes. An application for exemption of waterballast spaces in excess of 30 percent of the vessel's gross tonnage, calculated without any allowance for water ballast, shall be submitted for approval to the Commissioner of Customs, accompanied by a statement in writing from the vessel owner or his representative as to the circumstances of use or construction of the vessel which make such an allowance necessary and proper and verifying that the conditions specified in this paragraph have been and are met. Any change in the facts on the basis of which a water-ballast exemption is granted under this section shall be promptly reported to the collector of customs for his determination as to whether there has been a change in the use of spaces requiring an adjustment of tonnage under § 2.64.

(h) Water closets. Any public room or compartment, if of reasonable size, fitted with hopper or hoppers, is, for admeasurement purposes, a water closet. This definition includes a room or a compartment designated as a toilet, fitted with urinal, or urinals, shower bath or shower baths, in addition to the hopper or hoppers. A crew water closet is considered public if it serves more than one member of the crew.

(1) Wheelhouse. The space for sheltering the man or men at the wheel. If the space is a combined wheelhouse and chart room, only such space as is necessary for the proper steering of the vessel shall be exempted. Should the space be partly above and partly below the upper deck, such part above the line of continuation of said deck is exemptible. [28 F.R. 14553, Dec. 31, 1963, as amended by T.D. 66-57, 31 F.R. 4295, Mar. 11, 1966]

§ 2.44 Passenger cabins.

(a) Except as provided in § 2.80(b), passenger cabins and staterooms immediately on the upper deck to the hull, permanently closed-in and fitted up for permanent use of passengers, are to be included in gross tonnage. They will be exempted only when they have no berthing accommodations and have only temporary arrangements to protect passengers on short voyages from rain and the shipment of seas, constituting sheltered spaces under cover and open to the weather; that is, not enclosed.

(b) Cabins and staterooms when assigned for use of passengers only, constructed entirely above the first deck which is not a complete deck to the hull (see § 2.21), may be exempted from inclusion in tonnage. In the case of Army transports, colliers, supply ships, hospital ships, etc., the term "passengers" shall include all officers, enlisted men, and other persons who are not assigned to ship's duties and not entered on the ship's articles, and no deductions for spaces occupied by such persons shall be made; nor are cabins and staterooms occupied by them when situated on a deck not a deck to the hull to be included in gross tonnage.

(c) For admeasurement purposes a cabin is defined as an apartment of a vessel, or the portion of the apartment that is assigned for the exclusive use of passengers. A cabin may consist of staterooms, bathrooms, toilets, libraries, writing rooms, lounges, dining rooms, saloons, smoking rooms, play rooms, etc., individually or collectively. The following spaces-smoking room, lounge, foyer, library, and similar public spaces, with or without a stateroom-would, for instance, be considered cabins. In short, any passenger stateroom or public space reserved entirely for the use of passengers is to be considered as coming under the meaning of the word “cabin”.

(d) A passenger stateroom is defined as an apartment, or one of the units of an apartment on a vessel, intended primarily to afford sleeping and/or other accommodations for passengers traveling alone or together.

[28 F.R. 14553, Dec. 31, 1963, as amended by T.D. 66-57, 31 F.R. 4295, Mar. 11, 1966] § 2.45

Open superstructures on or above the upper deck.

(a) Treatment. Nothing shall be added to the gross tonnage for any sheltered space on or above the upper deck which is under cover and open to the weather; that is, not enclosed.

(b) Determination as to inclusion in gross tonnage. In deciding whether or not superstructures are permanent closed-in spaces and should be included in tonnage, the measurer should have regard to the character and structural condition of such erections.

(c) Tonnage openings. A forecastle, bridge, poop, or any other permanent superstructure on or above the upper deck to the hull, with one or more

openings in its sides or ends, not fitted with doors or other permanently attached means (except as provided for below) of closing them, shall be exempted from inclusion in gross tonnage if the opening or openings are in conformity with the following provisions:

(1) Two 3 x 4 foot tonnage openings. When there are in one of the end bulkheads, two tonnage openings, each 3 feet wide by 4 feet high in the clear, one on each side of the center line of the end bulkhead.

(2) One 4 x 5 foot tonnage opening. When there is in one of the end bulkheads, as near as is practicable to the center line of the space, one tonnage opening at least 4 feet wide by 5 feet high in the clear, or its equivalent. equivalent opening is considered to be one of at least 20 square feet in the clear, resulting from a breadth in excess of 4 feet and a height of not less than 3 feet.

An

(d) Intermediate bulkheads. If the space is subdivided by intermediate bulkheads, such bulkheads shall have an opening or openings of the same dimensions as prescribed above.

(e) Coamings. If coamings are fitted to tonnage openings, their height must not exceed 2 feet at any part.

(f) Permissible temporary closures for exterior bulkhead tonnage openings. Tonnage openings prescribed for the above-mentioned superstructures may be temporarily closed by shifting boards dropped into channel sections at the sides of such openings, or by plates or boards held in place by hook bolts, spaced not less than 1 foot apart, fitting over the stiffener bar at the sides, top, and bottom of such openings, or by a plate or boards held in place by bolts and cross pieces so arranged as not to be held in place by cleats or other attachments to, or bolts through the bulkhead. (See Figures 37 to 43, inclusive (§ 2.65).) Cover plates, etc., must fay against the bulkheads.

(g) Battening, gaskets, etc. In no case is the use of battening, caulking, or gaskets of any material permitted.

(h) Permanent fixtures. Cleats, stud bolts, hinges attached to, or bolts in bulkheads at the edges of tonnage openings are prohibited as they are considered to be part of the means, in conjunction with the plate or boards, of closing the tonnage opening.

(i) Closures for interior bulkhead tonnage openings. The same temporary means of closing the tonnage openings in interior bulkheads are permitted.

(j) Enclosure within an open space. An enclosure within an exempted space must be treated according to its use. [28 F.R. 14553, Dec. 31, 1963, as amended by T.D. 56378, 30 F.R. 3593, Mar. 18, 1965]

§ 2.46 Open shelter deck space.

(a) Space between decks. No space between the upper and shelter decks of a vessel shall be exempted from inclusion in gross tonnage as open shelter deck space unless there is in that shelter deck a permanent middle line tonnage opening which, except as provided in this paragraph, is at least 4 feet long in the clear and at least as wide, in the clear, as the after cargo hatch on that deck. If any such opening is less than the minimum size in the clear specified in this paragraph solely because one or more corners of that opening are rounded, that space shall be exempted, upon compliance with all applicable provisions of this section, in any case in which the radius of curvature of each such corner is not greater than 9 inches, or in any case in which a greater radius of curvature is required in writing by the United States Coast Guard or by a recognized classification society. In the latter case, a copy of that written requirement shall be filed in the office of the collector of customs by whom the vessel is admeasured.

(b) Position of middle line tonnage opening. The distance between the after edge of this tonnage opening and the aft side of the sternpost must not be less than one-twentieth the register length of the vessel, or if the tonnage opening is forward, its fore side must not be less than one-fifth the register length of the vessel from the stem.

(c) Coamings. The coamings of the middle line tonnage opening must not exceed 12 inches extreme mean height above the deck, including the beading, etc., at the top for confining the hatch covers. If any such opening is guarded by rails or stanchions they shall be so arranged that they may not be used to secure or assist in securing a cover over that opening.

(d) Cover. (1) When portable wood covers are fitted they may be held in place by lashings fitted to the under side of the covers; lashings may be of hemp, manila or other similar material.

(2) When a metal cover is used, it may be held in place by hook bolts spaced not less than 18 inches apart, passing through the cover plate and hooked over angle stiffeners or flanges fitted on the outside of the coamings; i. e., the bolts must not pass through the stiffeners or flanges on the coaming, nor must there be any other attachments on the coaming for fastening the cover.

(e) Opening not to be enclosed. The middle line tonnage opening in a shelter deck must not be within a superstructure of any type.

(f) Tonnage openings in shelter deck space. When the permanent deck opening is situated aft, there must be at least two openings, each 3 feet wide by 4 feet high in the clear, in each of the transverse bulkheads within the shelter deck space forward of said deck opening; or should the deck opening be forward, the same requirements apply to transverse bulkheads abaft such forward deck opening.

(g) Coamings. Coamings, if fitted, must not exceed 2 feet in height at any part.

(h) Temporary closure. The same temporary means of closing tonnage openings in the bulkheads of the well under the middle line tonnage opening in the shelter deck and in the intermediate bulkheads, if any, in the shelter deck space are permitted as described in § 2.45 (f).

(i) Well under middle line tonnage opening. The well under the middle line tonnage opening (in the shelter deck) must have a minimum length of 4 feet throughout its entire breadth and height, and shall be kept clear at all times.

(j) Scuppers. A scupper, having a 5inch minimum inside diameter, fitted with a screw down non-return valve geared to and operated from the shelter deck, must be fitted on each side of the upper deck in way of the permanent middle line tonnage opening in the shelter deck. (See Figure 44 (§ 2.65).)

(k) Means for closing. All openings in the upper deck to the hull must be provided with proper means for closing and battening down.

(1) Closed-in spaces. Any closed-in space within an open shelter deck space shall be treated according to its usage. [28 F.R. 14553, Dec. 31, 1963, as amended by T.D. 56378, 30 F.R. 3593, Mar. 18, 1965]

§ 2.47 An open structure on small craft.

(a) A house on a small craft is considered open to the weather and exempted from inclusion in tonnage provided the after end of such house is entirely open, from the under side of its roof beam down to a coaming not exceeding 3 inches in height, if there be a coaming, otherwise to the deck or line of same; and open in an athwartship direction from and to the inboard face of the end side stiffeners. (See Figures 45 and 46 (§ 2.65).) Closed-in spaces within an open erection will be treated according to their usage.

(b) Such an opening may be guarded by wire mesh screens and/or temporarily closed by canvas secured at the top and lashed down or buttoned in place at the sides and bottom.

§ 2.48 Open vessels.

(a) In ascertaining the tonnage of open vessels the upper edge of the upper strake shall form the boundary line of measurement, and a tonnage depth shall be taken from a line athwart the upper edge of said strake, at each point of division and each end of the tonnage length.

(b) An open vessel is one of any length without a deck, or with only a partial deck or partial decks, the total length of which is less than one-half her tonnage length.

(c) Further, a vessel having a tonnage length of less than 50 feet and a partial deck of any length or a single full length deck, which, in either case, lies more than one-sixth of the midship depth below the line of the upper edge of the upper strake to the usual point in the hold for taking the register depth, shall, for admeasurement purposes, be deemed an open vessel unless it has a mechanically refrigerated hold or holds. § 2.49 Deductions from gross tonnage.

(a) General. To ascertain the net tonnage, the tonnage of the following spaces meeting certain requirements shall be deducted from the gross tonnage.

(b) Requirements. No space shall be deducted unless it has been included previously in the vessel's gross tonnage; is reasonable in extent for the purpose to which it is appropriated; and is certified by marking as prescribed in paragraph (c) of this section showing that it is used exclusively for such purpose.

(c) Marking. The following markings are required by paragraph (b) of this section: For each space appropri

---

ated exclusively for the use of the master, including the master's bathroom, bedroom, dressing room, observation room, office, reception room, sitting room and water closet-"Certified for the Accommodation of Master"; for each space appropriated exclusively as a bedroom for the use of crew members, including officers other than the master-"Certified to Accommodate Seamen"; and for other deductible spaces-"Certified inserting the appropriate designation such as "Boatswain's Stores," "Chart House," "Dynamos," "Galley," "Hospital," "Messroom," "Office of Chief Engineer," "Pump Room," "Radio," "Steering Gear," "W. C." The following abbreviations may be used: "Cert. Accom. Master," "Cert. Accom. Seamen," "Cert. Boatswain's Stores," "Cert. Chart House," "Cert W. C." or "Cert. inserting the space designation. The marking shall at all times be embossed, center-punched, or otherwise permanently cut in metal, and painted over with oil paint in a light color on a dark background, or a dark color on a light background, or carved or branded at least three-eighths of an inch in wood over the doorway, on the inside of the deductible space. Roman letters and Arabic numerals at least one-half of an inch in height shall be used and shall be readily legible at all times. If desired, the marking may be made on a plate of metal (but not of other material) permanently fastened in place by means of welding, riveting, or lock-type screws. The metal certification plates may be fastened in place to a metal door frame, on the inside of the space, by means of a metal-to-metal synthetic contact adhesive if the vessel owner or his agent satisfactorily establishes that the bonding agent is currently acceptable to the U.S. Coast Guard or the Department of the Navy for use on merchant ships or naval vessels for affixing metal hull label plates; and, further, certifies that the metal-to-metal bond will be accomplished in accordance with the techniques recommended by the manufacturer of the bonding agent.

(d) Crew spaces. The tonnages of the spaces or compartments exclusively occupied by and appropriated to the use of the officers and crew of the vessel including:

Bathrooms. A bathroom is a compartment or a room containing (1) a bath tub, or (2) a bath tub and a water closet, or (3) a shower