Div 3Double Bottoms.

Division 3.—Double Bottoms.

Double bottoms.

11.—(1.) A ship the length of which is two hundred feet or more but less than two hundred and forty-nine feet shall be fitted with a watertight double bottom extending from the machinery space to, or to as near as is practicable to, the collision bulkhead.

(2.) Subject to the next succeeding sub-regulation, a ship the length of which is two hundred and forty-nine feet or more shall be fitted with a watertight double bottom extending from, or from as near as is practicable to, the collision bulkhead to, or to as near as is practicable to, the afterpeak bulkhead.

(3.) The last preceding sub-regulation does not require a double bottom to be fitted in the machinery space of a ship the length of which is less than three hundred and thirty feet.

Inner bottom of double bottom.

12.—(1.) The inner bottom of a double bottom fitted to a ship in pursuance of the last preceding regulation shall be continued out to the sides of the ship in such a manner as to protect the ship to the turn of the bilge.

(2.) The inner bottom shall be deemed to comply with the last preceding sub-regulation if the line of intersection of the outer edge of the margin plate of the inner bottom with the shell plating of the ship is not lower at any point than a horizontal plane passing through the point of intersection of the frame line amidships with a line inclined at an angle of twenty-five degrees to the base line amidships and cutting that base line at a point one half of the ship’s moulded breadth from the middle line.

Well not to be constructed in double bottom.

13.—(1.) Subject to sub-regulation (3.) of this regulation, a well shall not be constructed in a double bottom fitted to a ship in pursuance of this Division unless the Minister exempts the ship from the requirements of this sub-regulation.

(2.) The Minister shall not exempt a ship from the requirements of the last preceding sub-regulation unless he is satisfied that the protection given to the ship by the double bottom will not be diminished by reason of the exemption.

(3.) A well may be constructed in the double bottom of a ship for the purposes of drainage if the well—

(a) is not larger, and does not extend downwards further, than is necessary for that purpose;

(b) is not, at any point, less than eighteen inches from the inner edge of the margin plate of the inner bottom; and

(c) not being a well which is constructed at the after end of a shaft tunnel, is not, at any point, less than eighteen inches from the outer bottom.

Double bottom not required.

14. Nothing in this Division requires a double bottom to be fitted in a part of a ship immediately beneath a watertight compartment used exclusively for the carriage of liquids if, in the event of bottom or side damage to that part of the ship, the safety of the ship will not be impaired by reason of the absence of the double bottom.