(1) Where bulwarks on the weather portions of
freeboard or superstructure decks form wells, ample provision shall
be made for rapidly freeing the decks of water and for draining them.
Except as provided in paragraphs (2) and (3) of this Regulation, the
minimum freeing port area (A) on each side of the ship for each well
on the freeboard deck shall be that given by the following formulae
in cases where the sheer in way of the well is standard or greater
than standard. The minimum area for each well on superstructure decks
shall be one-half of the area given by the formulae.
-
Where the length of bulwark (l) in the well
is 20 metres or less
where l exceeds 20 metres
l need in no case be taken as greater
than 0.7 L.
If the bulwark is more than 1.2 metres in average height the
required area shall be increased by 0.004 square metres per metre
of length of well for each 0.1 metre difference in height. If the
bulwark is less than 0.9 metre in average height, the required area
may be decreased by 0.004 square metres per metre of length of well
for each 0.1 metre difference in height.
Or,
where the length of bulwark (l) in the well is
66 feet or less
where l exceeds 66 feet
l need in no case be taken as greater
than 0.7 L.
If the bulwark is more than 3.9 feet in average height the required
area shall be increased by 0.04 square feet per foot of length of
well for each foot difference in height. If the bulwark is less than
3 feet in average height, the required area may be decreased by 0.04
square feet per foot of length for each foot difference in height.
(2) In ships with no sheer the calculated area
shall be increased by 50 per cent. Where the sheer is less than the
standard the percentage shall be obtained by interpolation.
(3) Where a ship is fitted with a trunk which
does not comply with the requirements of Regulation
36 (1) (e) or where continuous or substantially continuous
hatchway side coamings are fitted between detached superstructures
the minimum area of the freeing port openings shall be calculated
from the following table:
| BREADTH OF HATCHWAY OR
TRUNK IN RELATION TO THE BREADTH OF SHIP
|
AREA OF FREEING PORTS
IN RELATION TO THE TOTAL AREA OF THE BULWARKS
|
| 40% or less
|
20%
|
| 75% or more
|
10%
|
The area of freeing ports at intermediate breadths
shall be obtained by linear interpolation.
(4) In ships having superstructures which are
open at either or both ends, adequate provision for freeing the space
within such superstructures shall be provided to the satisfaction
of the Administration.
(5) The lower edges of the freeing ports shall
be as near the deck as practicable. Two-thirds of the freeing port
area required shall be provided in the half of the well nearest the
lowest point of the sheer curve.
(6) All such openings in the bulwarks shall be
protected by rails or bars spaced approximately 230 millimetres (9
inches) apart. If shutters are fitted to freeing ports, ample clearance
shall be provided to prevent jamming. Hinges shall have pins or bearings
of non-corrodible material. If shutters are fitted with securing appliances,
these appliances shall be of approved construction.