2.4.1 Cargo tanks shall be located at the following
distances inboard:
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.1 Type 1G ships: from the moulded line of the
outer shell, not less than the transverse extent of damage specified
in 2.3.1.1.2 and, from the moulded line of the bottom shell at centreline,
not less than the vertical extent of damage specified in 2.3.1.2.3,
and nowhere less than "d" where "d" is as
follows:
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.1 for Vc below or equal 1,000 m3, d = 0.8 m;
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.2 for 1,000 m3 < Vc < 5,000
m3, d = 0.75 + Vc x 0.2/4,000 m;
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.3 for 5,000 m3 ≤ Vc < 30,000
m3, d = 0.8 + Vc/25,000 m; and
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.4 for Vc ≥ 30,000 m3, d =
2 m,
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where:
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- Vc corresponds to 100% of the gross design
volume of the individual cargo tank at 20°C, including domes and
appendages (see figures 2.1 and 2.2). For the purpose of cargo tank
protective distances, the cargo tank volume is the aggregate volume
of all the parts of tank that have a common bulkhead(s); and
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- "d" is measured at any cross section
at a right angle from the moulded line of outer shell.
Tank
size limitations may apply to type 1G ship cargoes in accordance with
chapter 17.
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.2 Types 2G/2PG: from the moulded line of the
bottom shell at centreline not less than the vertical extent of damage
specified in 2.3.1.2.3 and nowhere less than "d" as indicated
in 2.4.1.1 (see figures 2.1 and 2.3).
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.3 Type 3G ships: from the moulded line of the
bottom shell at centreline not less than the vertical extent of damage
specified in 2.3.1.2.3 and nowhere less than "d", where
"d" = 0.8 m from the moulded line of outer shell (see
figures 2.1 and 2.4).
2.4.2 For the purpose of tank location, the vertical
extent of bottom damage shall be measured to the inner bottom when
membrane or semi-membrane tanks are used, otherwise to the bottom
of the cargo tanks. The transverse extent of side damage shall be
measured to the longitudinal bulkhead when membrane or semi-membrane
tanks are used, otherwise to the side of the cargo tanks. The distances
indicated in 2.3 and 2.4 shall be applied as in figures 2.5(a) to
(e). These distances shall be measured plate to plate, from the moulded
line to the moulded line, excluding insulation.
2.4.3 Except for type 1G ships, suction wells
installed in cargo tanks may protrude into the vertical extent of
bottom damage specified in 2.3.1.2.3 provided that such wells are
as small as practicable and the protrusion below the inner bottom
plating does not exceed 25% of the depth of the double bottom or 350
mm, whichever is less. Where there is no double bottom, the protrusion
below the upper limit of bottom damage shall not exceed 350 mm. Suction
wells installed in accordance with this paragraph may be ignored when
determining the compartments affected by damage.
2.4.4 Cargo tanks shall not be located forward
of the collision bulkhead.