SAFETY OF LIFE AT SEA 



C27 



1,950 -4L ^^ . , 

 Si = j^^ (L in feet) 



3,712-25L ^, . 

 Si = j-g (L m metres) 



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 sub-paragraph (ii) (2) of this paragraph; of those having a 

 criterion numeral between Sj and 123 by the factor F obtained by 

 linear interpolation between unity and the factor BB using the 

 formula : — 



P^ (1-BB)_(G-S,^ 



123 - S, 



except that in either of the two latter cases if the factor so obtained 

 is less than 50 the subdivision may be governed by a factor not 

 exceeding 50. 



(5) The subdivision abaft tke fore peak of ships less than 430 feet (or 

 131 metres) but not less than 180 feet (or 55 metres) in length 

 and having a criterion numeral less than S, and of all ships less 

 than 180 feet (or 55 metres) 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. 



Regulation 6 



Special Rules concerning Subdivision 



(a) Where in a portion or portions of a ship the watertight bulkheads are 

 carried to a higher deck than in the remainder of the ship and it is desired to 

 take advantage of this higher extension of the bulkheads in calculating the 

 floodable length, separate margin lines may be used for each such portion of 

 the ship provided that — 



(i) the sides of the ship are extended throughout the ship's length to the 

 deck corresponding to the upper margin line and all openings in the 

 shell plating below this deck throughout the length of the ship are 

 treated as being below a margin line, for the purposes of 

 Regulation 14 of this Chapter; and 



Ch. 2 



