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Merchant Shipping Act, 1951 (Act No. 57 of 1951)

Schedules

Second Schedule

Protocol of 1978 Relating to the International Convention for the Safety of Life at Sea, 1974

Annex

Chapter II–1 : Construction — Subdivision and Stability, Machinery and Electrical Installations

Part B — Subdivision and Stability

Regulation 5 : Permissible length of compartments

 

(a) Ships shall be as efficiently subdivided as is possible having regard to the nature of the service for which they are intended. The degree of subdivision shall vary with the length of the ship and with the service, in such manner that the highest degree of subdivision corresponds with the ships of greatest length, primarily engaged in the carriage of passengers.

 

(b) Factor of subdivision.— The maximum permissible length of a compartment having its centre at any point in the ship’s length is obtained from the floodable length by multiplying the latter by an appropriate factor called the factor of subdivision.

The factor of subdivision shall depend on the length of the ship, and for a given length shall vary according to the nature of the service for which the ship is intended. It shall decrease in a regular and continuous manner—

(i) as the length of the ship increases; and
(ii) from a factor A, applicable to ships primarily engaged in the carriage of cargo, to a factor B, applicable to ships primarily engaged in the carriage of passengers.

The variations of the factors A and B shall be expressed by the following formulae (I) and (II) where L is the length of the ship as defined in Regulation 2 of this Chapter:

 

L in metres

 

 

L in feet

 

 

L in metres

 

 

L in feet

 

 

 

(c) Criterion of service.— For a ship of given length the appropriate factor of subdivision shall be determined The Criterion of Service Numeral (hereinafter called the Criterion Numeral) as given by the following formulae (III) and (IV) where—
Cs = the Criterion Numeral;
L = length of the ship, as defined in Regulation 2 of this Chapter;
M = the volume of the machinery space, as defined in Regulation 2 of this Chapter; with the addition thereto of the volume of any permanent oil fuel bunkers which may be situated above the inner bottom and before or abaft the machinery space;
P = the whole volume of the passenger spaces below the margin line, as defined in Regulation 2 of this Chapter;
V = the whole volume of the ship below the margin line;
P1 = KN where:

N =        number of passengers for which the ship is to be certified, and

K has the following values:

Value of K

Length in metres and volumes in cubic metres                0,056L:

Length in feet and volumes in cubic feet                0,6L:

 

Where the value of KN is greater than the sum of P and the whole volume of the actual passenger spaces above the margin line, the figure to be taken as P is that sum or two-thirds KN, whichever is the greater.

 

When P1 is greater than P—

 

 

and in other cases—

 

 

For ships not having a continuous bulkhead deck the volumes are to be taken up to the actual margin lines used in determining the floodable lengths.

 

(d) Rules for subdivision of ships other than those covered by paragraph (e) of this Regulation.—(i) The subdivision abaft the forepeak of ships 131 metres (430 feet) in length and upwards having a criterion numeral of 23 or less shall be governed by the factor A given by formula (I); of those having a criterion numeral of 123 or more by the factor B given by formula (II); and of those having a criterion numeral between 23 and 123 by the factor F obtained by linear interpolation between the factors A and B, using the formula:

 

 

Nevertheless, where the criterion numeral is equal to 45 or more and simultaneously the computed factor of subdivision as given by formula (V) is 0,65 or less, but more than 0,50, the subdivision abaft the forepeak shall be governed by the factor 0,50.

 

Where the factor F is less than 0,40 and it is shown to the satisfaction of the Administration to be impracticable to comply with the factor F in a machinery compartment of the ship, the subdivision of such compartment may be governed by an increased factor, which, however, shall not exceed 0,40.

(ii) The subdivision abaft the forepeak of ships less than 131 metres (430 feet) but not less than 79 metres (260 feet) in length having a criterion numeral equal to S, where—

 

 

shall be governed by the factor unity; of those having a criterion numeral of 123 or more by the factor B given by the formula (II); of those having a criterion numeral between S and 123 by the factor F obtained by linear interpolation between unity and the factor B using the formula:

 

 

(iii) The subdivision abaft the forepeak of ships less than 131 metres (430 feet) but not less than 79 metres (260 feet) in length and having a criterion numeral less than S, and of all ships less than 79 metres (260 feet) in length shall be governed by the factor unity, unless, in either case, it is shown to the satisfaction of the Administration to be impracticable to comply with this 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.
(iv) The provisions of subparagraph (III) of this paragraph shall apply also to ships of whatever length, which are to be certified to carry a number of passengers exceeding 12 but not exceeding—

 

 

 

(e) Special standards of subdivision for ships which are permitted under paragraph (c) of Regulation 27 of Chapter III to carry a number of persons on board in excess of the lifeboat capacity provided and are required under paragraph (d) of Regulation 1 of this Chapter to comply with special provisions.—
(i)
(a) In the case of ships primarily engaged in the carriage of passengers, the subdivision abaft the forepeak shall be governed by a factor of 0,50 or by the factor determined according to paragraphs (c) and (d) of this Regulation, if less than 0,50.
(b) In the case of such ships less than 91,5 metres (300 feet) in length, if the Administration is satisfied that compliance with such factor would be impracticable in a compartment, it may allow the length of that compartment to be governed by a higher factor provided the factor used is the lowest that is practicable and reasonable in the circumstances.
(ii) Where, in the case of any ship whether less than 91,5 metres (300 feet) or not, the necessity of carrying appreciable quantities of cargo makes it impracticable to require the subdivision abaft the forepeak to be governed by a factor not exceeding 0,50 the standard of subdivision to be applied shall be determined in accordance with the following subparagraphs (1) t o (5), subject to the condition that where the Administration is satisfied that insistence on strict compliance in any respect would be unreasonable, it may allow such alternative arrangement of the water tight bulkheads as appears to be justified on merits and will not diminish the general effectiveness of the subdivision.
(a) The provisions of paragraph (c) of this Regulation relating to the criterion numeral shall apply with the exception that in calculating the value of P for berthed passengers K is to have the value defined in paragraph (c) of this Regulation, or 3,55 cubic metres (125 cubic feet), whichever is the greater, and for unberthed passengers K is to have the value 3,55 cubic metres (125 cubic feet).
(b) The factor B in paragraph (b) of this Regulation shall be replaced by the factor BB determined by the following formula:

L in metres

 

 

L in feet

 

 

(c) The subdivision abaft the forepeak of ships 131 metres (430 feet) in length and upwards having a criterion numeral of 23 or less shall be governed by the factor A given by formula (I) in paragraph (b) of this Regulation; of those having a criterion numeral of 123 of more by the factor BB given by the formula in subparagraph (ii) (2) of this paragraph; and of those having a criterion numeral between 23 and 123 by the factor F obtained by linear interpolation between the factors A and BB, using the formula:

 

 

except that if the factor F so obtained is less than 0,50 the factor to be used shall be either 0,50 or the factor calculated according to the provisions of subparagraph (d) (i) of this Regulation, whichever is the smaller.

 

(d) The subdivision abaft the forepeak of ships less than 131 metres (430 feet) but not less than 55 metres (180 feet) in length having a criterion numeral equal to S1 where—

 

 

shall be governed by the factor unity; of those having a criterion numeral of 123 or more by the factor BB given by the formula in subparagraph (ii) (2) of this paragraph; of those having a criterion numeral between S08 and 123 by the factor F obtained by linear interpolation between unity and the factor BB using the formula:

 

 

except that in either of the two latter cases if the factor so obtained is less than 0,50 the subdivision may be governed by a factor not exceeding 0,50.

(e) The subdivision abaft the forepeak of ships less than 131 metres (430 feet) but not less than 55 metres (180 feet) in length and having a criterion numeral less than S and of all ships less than 55 metres (180 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 this factor in particular compartments, in which event the Administration may allow such relaxations in respect of those compartments as appear to be justified, having regard to all the circumstances, provided that the aftermost compartment and as many as possible of the forward compartments (between the forepeak and the after end of the machinery space) shall be kept within the floodable length.