polation between unity and the factor "B," using the formula

where Cs is the criterion numeral with a value between S and 123.

Those having a criterion numeral less than "S" shall be governed by the factor unity, unless it is shown to the satisfaction of the Administration to be impracticable to comply with that factor in any part of the ship, in which case the Administration may allow such relaxation as may appear to be justified, having regard to all the circumstances (p. 40, p. 34, p. 41, Reg. IV, par. 3, subparagraphs b and c).

Subdivision of Ships Less than 260 Feet Long.

39. The subdivision of all ships less than 260 feet in length shall be governed by the factor unity, unless it is shown to the satisfaction of the Administration to be impracticable to comply with that factor in any part of the ship, in which case the Administration may allow such relaxation as may appear to be justified, having regard to all the circumstances (p. 40, p. 34, p. 41, Reg. IV, par. 3, subparagraph c).

Subdivision of Ships Carrying a Small Number of Passengers. 40. Ships of whatever length, which are to be certified to carry a number of passengers exceeding 12 but not exceeding the numL2 ber or 50, whichever is the less, shall be governed for 7000 subdivision by a factor not greater than unity, unless it is shown to the satisfaction of the Administration to be impracticable to comply with that factor in any part of the ship, in which case the Administration may allow such relaxation as may appear to be justified, having regard to all the circumstances. To deterL2 mine the number the length of the ship L (see definition, 7000' paragraph 30 of this statement), is taken in feet (p. 40, p. 34, p. 41, Reg. IV, par. 3, subparagraph d).

SPECIAL RULES CONCERNING SUBDIVISION

Pairs of Compartments.

41. A compartment may exceed the permissible length determined by the rules given in paragraphs 37 to 39, provided

the combined length of each pair of adjacent compartments to which the compartment in question is common does not exceed either the floodable length, or twice the permissible length, whichever is the less (see also paragraph 45 of this statement).

If one of the two adjacent compartments is situated inside the machinery space, and the second is situated outside the machinery space, and the average permeability of the portion of the ship in which the second is situated differs from that of the machinery space, the combined length of the two compartments shall be adjusted to the mean average permeability of the two portions of the ship in which the compartments are situated.

Where the two adjacent compartments have different factors of subdivision, the combined length of the two compartments shall be determined proportionately (p. 40, p. 34, p. 42, Reg. V, par. 1).

Stern Tubes.

42. In all cases stern tubes shall be inclosed in watertight spaces. The stern gland shall be situated within a watertight shaft tunnel or other space of such volume that if flooded by leakage through the stern gland the margin line will not be submerged (p. 8, p. 8, p. 10, Art. 6; p. 42, p. 35, p. 43, Reg. VI, par. 3).

Subdivision within a Main Compartment.

43. Where a main transverse watertight compartment contains local subdivision, and it can be shown to the satisfaction of the Administration that after any assumed side damage extending over 10 feet plus 2 per cent of the length of the ship, the whole of the main compartment will not be flooded, a proportionate allowance may be made in the permissible length otherwise required for such compartment.

In such a case the volume of effective buoyancy assumed on the undamaged side shall not be greater than that assumed on the damaged side (p. 41, p. 35, p. 43, Reg. V, par. 7).

Steps and Recesses in Bulkheads.

44. A main transverse bulkhead may be recessed provided that all parts of the recess lie inboard of vertical surfaces on both sides of the ship situated at a distance from the shell plating equal to one-fifth of the breadth of the ship (see definition, paragraph 30 of this statement), measured at right angles to the centerline at the level of the deepest subdivision load line.

Any part of a recess which lies outside these limits shall be dealt with as a step in accordance with the following requirements:

A main transverse bulkhead may be stepped provided that

(a) The combined length of the two compartments separated by the bulkhead in question does not exceed 90 per cent of the floodable length, or

(b) Additional subdivision is provided in way of the step to maintain the same measure of safety as that secured by a plane bulkhead.

Where a main transverse bulkhead is recessed or stepped, an equivalent plane bulkhead shall be used in determining the subdivision (p. 41, p. 35, p. 42, Reg. V, paragraphs 3, 4, and 5). Minimum Distance Between Transverse Subdivision Bulkheads.

45. If the distance between adjacent transverse bulkheads in either of the following cases is less than 10 feet plus 2 per cent of the length of the ship, only one of these bulkheads shall be regarded as forming part of the subdivision of the ship in accordance with the rules given in paragraphs 37 to 40 of this statement.

(a) Two adjacent main transverse bulkheads, or their equivalent plane bulkheads.

(b) The transverse planes passing through the nearest stepped portions of adjacent bulkheads (p. 41, p. 35, p. 42, Reg. V, par. 6).

Peak and Machinery Space Bulkheads.

46. Every ship shall have a forepeak or collision bulkhead, which shall be watertight up to the bulkhead deck. This bulkhead shall be fitted not less than 5 per cent of the length of the ship, and not more than 10 feet plus 5 per cent of the length of the ship from the forward perpendicular.

If the ship has a long forward superstructure, the forepeak bulkhead shall be extended weathertight to the deck next above the bulkhead deck. The extension need not be fitted directly over the bulkhead below, provided it is at least 5 per cent of the length of the ship from the forward perpendicular, and the part of the bulkhead deck which forms the step is made effectively weathertight.

An afterpeak bulkhead, also bulkheads dividing the machinery space (see definition, paragraph 30 of this statement) from the

cargo and passenger spaces forward, shall be fitted and made watertight up to the bulkhead deck. The afterpeak bulkhead may, however, be stopped below the bulkhead deck, provided the degree of safety of the ship as regards subdivision is not diminished (p. 8, p. 8, p. 10, Art. 6; p. 42, p. 35, p. 43, Reg. VI, paragraphs 1 and 2).

WATERTIGHT DECKS, INNER SKINS, LONGITUDINAL BULKHEADS

Provisions Against Listing.

47. Where it is proposed to fit watertight decks, inner skins or longitudinal bulkheads watertight or non-watertight, the Administration shall be satisfied that the safety of the ship will not be diminished in any respect, particularly having in view the possible listing effect of flooding in way of such structural arrangements (p. 42, p. 35, p. 43, Reg. V, par. 8).

Stability Test.

TRANSVERSE STABILITY

48. Every new passenger ship shall be inclined upon its completion and the elements of its stability determined. The operating personnel shall be supplied with such information on this subject as is necessary to permit efficient handling of the ship p. 8, p. 8, p. 10, Art. 8).

The recommendations attached to the Convention, as regards construction, state:

The necessity for and practicability of adopting stability regulations have been considered by this Conference and the opinion has been reached that at this time it is practicable to adopt only the general requirement for stability tests on new passenger ships contained in Article 8. The Conference desires, however, to draw the attention of the Contracting Governments to the desirability of a study by each Administration of the subject of stability for the different national types of ships and trades, and of the exchange of information on this subject between these Contracting Governments (p. 105, p. 86, p. 112).

SUBDIVISION LOADLINES, ASSIGNING, MARKING,

RECORDING

Subdivision Loadline; Assigning and Marking.

49. In order that the required degree of subdivision shall be maintained, a loadline corresponding to the approved subdivision

draft shall be assigned and marked on the ship's sides. A ship having spaces which are specially adapted for the accommodation. of passengers and the carriage of cargo alternatively may, if the owners desire, have one or more additional loadlines assigned and marked to correspond with the subdivision drafts which the Administration may approve for the alternative service conditions. The freeboard corresponding to each approved subdivision loadline, and the conditions of service for which it is approved, shall be clearly indicated on the Safety Certificate. Subdivision loadlines shall be marked and recorded in the manner provided in Regulation VII, which is paragraph 50 of this statement (p. 7, p. 7, p. 9, Art. 5, par. 4).

Subdivision Loadline; Recording, and Limitations on Loading.

50. (1) The subdivision loadlines assigned and marked under the provisions of Article 5 of the Convention shall be recorded in the Safety Certificate, and shall be distinguished by the notation C.1 for the principal passenger condition, and C.2, C.3, etc., for the alternative conditions.

(2) The freeboard corresponding to each of these loadlines inserted in the Safety Certificate shall be measured at the same position and from the same deck line as the freeboards determined by recognized national Freeboard Regulations.

(3) In no case shall any subdivision loadline mark be placed above the deepest loadline in salt water as determined by the strength of the ship and/or recognized national Freeboard Regulations.

(4) Whatever may be the position of the subdivision loadline marks, a ship shall in no case be loaded so as to submerge the loadline mark appropriate to the season and locality as determined by the recognized national Freeboard Regulations (p. 42, p. 36, p. 44, Reg. VII).

CONSTRUCTION AND INITIAL TESTING OF WATERTIGHT BULKHEADS, WATERTIGHT DECKS,

WATERTIGHT TRUNKS, ETC.

Bulkheads and Decks; Construction.

51. Watertight subdivision bulkheads, whether transverse or longitudinal, shall be constructed in such a manner that they shall be capable of supporting, with a proper margin of resistance, the pressure due to a head of water up to the margin line in way of each bulkhead. The construction of these bulkheads shall be to the satisfaction of the Administration.