The ship when loaded to summer load water line will remain afloat in a satisfactory condition of equilibrium after flooding of any one of the empty assumed permeability of 0.95 excluding the machinery space
If the machinery space is over 225 metres in length the machinery space shall be treated as a floodable compartment but with a permeability of 0.85.
After the flooding:-
- The final water line after flooding is below the lower edge of any opening through which progressive flooding may take place;
- The maximum angle of heel due to unsymmetrical flooding should be to the order of 15 degrees;
- The meta centric height in flooded condition is positive.
Recommendation applies for new oil tankers, chemical tankers and gas carriers contracted for construction on or after 1st January 2010 subject to review of impact on ships undergoing approval and delivering after said date. ‘contracted for construction’ date means the date on which the contract to build the vessel is signed between the prospective owner and the shipbuilder.
The relevant calculations may be based upon the following assumptions:
- The vertical extent of damage is equal to the depth of the vessel .The penetration of damage is not more than B/5; No main transverse bulkhead is damaged
- A cargo vessel fulfilling the above criteria will be assigned a reduced freeboard not more than 60% the difference of Type A & B vessel.
A type B vessel which can withstand the flooding of two adjacent fore and aft compartments will be assigned a freeboard up to Type A vessel.