INTERNATIONAL CONVENTION SAFETY OF LIFE AT SEA. 293 



cent to 60 per cent, and for the spaces in the double bottoms and trimming tanks there has 

 been an increase from 40 per cent to 95 per cent. This great increase in the values assigned 

 to "permeability percentages" must be given due weight when considering the "permissible 

 length of compartments" provided for in Article VIII of the Regulations. At first sight, 

 the "factors of subdivision" given in the table of paragraph 3 of Article VIII may appear 

 unduly large, since efficiency of subdivision is inversely as the value of the factor of subdi- 

 vision. The American delegation was very desirous of agreeing upon more stringent re- 

 quirements in this respect, but the data and experience available convinced their colleagues of 

 other countries that the requirements of paragraph 3, Article VIII, were as high as could rea- 

 sonably be imposed. These requirements, however, as well as those of Article IX, were dis- 

 tinctly specified as minimum requirements, and Article X made definite provision for making 

 official notation on the "Safety Certificate" of a vessel when such vessel exceeded the require- 

 ments imposed by Article VIII. The effect of this provision has already been referred to 

 and need not be here enlarged upon. 



As illustrating the meaning of the table in Article VIII, it may be stated, in general 

 terms, that all vessels whose "factor of subdivision" is 0.5 or less are vessels any two of 

 whose adjoining main transverse compartments may be flooded without resultant founder- 

 ing of the vessel. This, of course, is for the vessel in the deeply laden condition and using 

 the percentages of permeability referred to above. When the vessel is not loaded to the 

 deep-load water line — as is most usually the case with passenger vessels — there is an addi- 

 tional "margin of safety" by reason of the correspondingly increased reserve of buoyancy. 

 There is also an increase in the reserve of buoyancy as the "factor of subdivision" decreases 

 in value. 



As noted in paragraph 3 of Article VIII, two classes of vessels were considered by the 

 conference, viz., "mixed cargo and passenger vessels" and "vessels primarily engaged in 

 the transportation of passengers," the requirements being more stringent for the last-named 

 class. For vessels whose service is such as to place them in a category between these two 

 classes a "criterion of service" is authorized, the determination of which is provided for in 

 Article 30 of the convention. 



Article IX of the regulations gives in some detail additional requirements as to subdi- 

 vision, especially as regards increase in floodable length of forward end of vessel, the maxi- 

 mum length of compartments, and restrictions as to recesses and steps in bulkheads. 



PEAK AND MACHINERY BULKHEADS. 



Article 18 of the convention and Article XI of the regulations establish requirements 

 as to location of peak and machinery space bulkheads. 



While the principal marine registration and classification societies already prescribe cer- 

 tain requirements for such bulkheads for vessels classed by them, the action of the confer- 

 ence makes these requirements obligatory for all new vessels covered by the convention 

 whether "classed" or not. Provision is also made in Articles 19 of the convention and XII 

 of the regulations for fitting fireproof bulkheads which will serve to retard the spread of 

 fire; it is also specified that the distance between any two consecutive fireproof bulkheads 

 shall not be greater than 40 meters, that recesses in these bulkheads shall be fireproof, and 

 that openings shall be fitted with fireproof doors. 



