What are damage stability criteria for passenger ships as per SOLAS?

Passenger ships – Longitudinal extent of damage;

3m + 3% of L or, 11m whichever is least.
Where the required factor of subdivision is 0.33 or less the longitudinal extent must be increased to include flooding of any three consecutive compartments.
 
Passenger ships – Transverse extent of damage;20% of B measured inboard from the ship’s side at right angles to the centreline at the level of the deepest subdivision load waterline taken parallel to the keel 
Passenger ships – Vertical extent of damage;From the baseline upwards without limit
Any other damage;If any damage of a lesser extent would may cause a more severe condition regarding heel or loss of metacentric height, such damage shall be assumed for the purpose of the calculation
Passenger ships – When does the damage stability apply?;In the final stage after damage and after equalisation
Passenger ships damage stability – Residual area under curve;At least 0.015mr measured from the angle of equilibrium to the lesser of;
– Angle of flooding
– 22 deg from upright (one flooded compartment) or 27 deg from upright (two or more flooded compartments)
Passenger ships damage stability – Range of positive stability;At least 15 deg beyond angle of equilibrium
Passenger ships damage stability -Maximum GZ;Residual righting lever (GZ) value to occur within the range of positive stability when determined by the formula;
GZ(m) = heeling moment / displacement (+ 0.04)
When the heeling moment is taken as the greater value of any one of the following effects;
– Crowding of passengers to one side of the ship
– Launching of all fully loaded, davit launched survival craft on one side of the ship
– Pressure of wind on the side of the ship
In no case shall the GZ value so determined be less than 0.1m
Passenger ships damage stability – Assumed flooding;Sufficient intact stability in all conditions to withstand flooding of any 1 main compartment or;
-Where factor of subdivision is 0.33 – 0.5 to withstand the flooding of any 2 adjacent compartments or;
– Where factor of subdivision os 0.33 or less to withst

and the flooding of any 3 adjacent main compartments

Passenger ships; Define ‘Margin Line’A line drawn at least 76mm below the upper surface of the the bulkhead deck at the side of a subdivided ship
Passenger ships; Define ‘Bulkhead Deck’The uppermost deck to which the transverse watertight bulkheads are carried
Passenger ships; Define ‘Factor of Subdivision’Is a number with a maximum value of 1. It varies inversely as the length of the vessel and number of passengers increase.
i.e. Longer vessel, more passengers = Smaller F
Passenger ships; Define ‘Permissible length’Equal to the Floodable length x Factor of Subdivision (F)The The maximum length of a compartment shall not exceed it’s ‘Permissible length’
Passenger ships; Define ‘Floodable length’Maximum length of that portion having it’s centre at a given point which can be flooded without submerging any part of the margin line when the ship has no list

ANUBHAV GAUTAM