C30 SAFETY OF LIFE AT SEA 



design characteristics of the ship and the arrangement and configuration 

 the damaged compartments. In making these calculations the ship is to 

 assumed in the worst anticipated service condition as regards stability. 





(ii) Where it is proposed to fit decks, inner skins or longitudinal 

 bulkheads of suflBcient tightness to seriously restrict the flow of water, the 

 Administration shall be satisfied that proper consideration is given to such 

 restrictions in the calculations. 



(iii) In cases where the Administration considers the range of stability 

 dn the damaged condition to be doubtful, it may require investigation thereof. 



(c) For the purpose of making damage stability calculations the volume 

 and surface permeabilities shall be in general as follows : 



Spaces Permeability 



Appropriated to Cargo, Coal or Stores 60 



Occupied by Accommodation 95 



Occupied by Machinery 85 



Intended for Liquids or 95* 



*Whichever results in the more severe requirements. 



Higher surface permeabilities are to be assumed in respect of spaces which, 

 in the vicinity of the damage waterplane, contain no substantial quantity of 

 accommodation or machinery and spaces which are not generally occupied 

 by any substantial quantity of cargo or stores. 



{d) Assumed extent of damage shall be as follows: — 



(i) longitudinal extent: 10 feet (or 3 05 metres) plus 3 per cent, of the 

 length of the ship, or 35 feet (or 10 67 metres) whichever is the 

 less. Where the required factor of subdivision is 33 or less the 

 assumed longitudinal extent of damage shall be increased as 

 necessary so as to include any two consecutive main transverse 

 watertight bulkheads; 



(ii) transverse extent (measured inboard from the ship's side, at right 

 angles to the centre line at the level of the deepest subdivision load 

 line) : a distance of one-fifth of the breadth of the ship, as defined 

 in Regulation 2 of this Chapter; and 



(iii) vertical extent : from the base line upwards without limit. 



(iv) If any damage of lesser extent than that indicated in sub-paragraphs 

 (i), (ii) and (iii) of this paragraph would result in a more severe 

 condition regarding heel or loss of metacentric height, such damage 

 shall be assumed in the calculations. 



Ch. 2 



