To ensure that the cargo containment and handling systems are located in such a way that
the consequences of any release of cargo will be minimized, and to provide safe access
for operation and inspection. This chapter describes the minimum containment and
handling provisions for all liquid cargoes. Additional provisions for those products
with higher levels of hazard are described in chapter 4.
3.1 Cargo segregation
3.1.1 Tanks containing cargoes, residues of cargoes or mixtures containing cargoes
subject to the present Code should be segregated from machinery spaces as defined in
1.2.28 and 1.2.29, accommodation and service spaces and from drinking water and stores
for human consumption by means of a cofferdam, void space, cargo pump-room, pump-room,
empty tank, oil fuel tank, or other similar space.footnote On-deck stowage of permanently attached deck tanks or
installation of independent tanks in otherwise empty hold spaces should be considered as
satisfying this provision.
3.1.1.1 For pollution hazards only substances having a flashpoint exceeding 60°C, the
segregation provisions need only be met for accommodation spaces, drinking water and
stores for human consumption.
3.1.2 Cargoes, residues of cargoes or mixtures containing cargoes which react in a
hazardous manner with other cargoes or oil fuels should:
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.1 be segregated from such other cargoes or oil fuels by means of a cofferdam,
void space, cargo pump-room, pump-room, empty tank, or tank containing a mutually
compatible cargo;
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.2 have separate pumping and piping systems which should not pass through other
cargo tanks containing such cargoes, unless encased in a tunnel; and
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.3 have separate tank venting systems.
3.1.3 Cargo piping should not pass through any accommodation, service spaces or
machinery space of category A.
3.1.4 If cargo piping systems or cargo venting systems are required to be separated,
this separation may be achieved by the use of design or operational methods. Operational
methods should not be used within a cargo tank or a cofferdam surrounding the cargo
tanks, if entry into the cofferdam is required, and should consist of one of the
following types:
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.1 removing spool pieces or valves and blanking the pipe ends;
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.2 arrangements of two spectacle flanges in series, with provisions for detecting
leakage into the pipe between the two spectacle flanges; and
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.3 blind flange valve with double shut-off and with provisions for detecting
leakage in valve body.
3.1.5 Pumps, ballast lines, vent lines and other similar equipment serving ballast tanks
should be separated from similar equipment serving cargo tanks and of cargo tanks
themselves.
3.1.6 For access to all spaces, the minimum spacing between cargo tank boundaries and
adjacent vessel structure should be 600 mm.
3.1.7 Cargo tanks other than those certified to carry substances subject to the
provisions of chapter 4 may extend to the deck plating. Where cargo is handled on the
deck area above a cargo tank, the cargo tank may not extend to the deck plating unless a
continuous permanent deck sheathing of min 50 mm of wood or other suitable material of
equivalent thickness and construction is fitted.
3.1.8 Cargoes subject to the present Code should not be carried in either the fore or
aft peak tanks.
3.2 Accommodation, service and machinery spaces and control stations
3.2.1 Accommodation or service spaces or control stations should not be located within
the cargo area.
3.2.2 For a vessel certified to carry safety hazard substances, entrances, air inlets
and openings to accommodation, service and machinery spaces and control stations may be
accepted in bulkheads facing the cargo deck area if they are located outside the deck
area defined in 1.2.7.2.
3.2.3 Propulsion shafts may be routed through cargo pump-rooms.
3.3 Access to spaces in the cargo area
3.3.1 Unless expressly provided otherwise in chapter 4, the following should apply:
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.1 For pollution hazard only substances, at least one access to cargo tanks should
be direct from the open deck and designed such as to ensure complete inspection of
those substances.
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.2 For safety hazard substances, at least one access to each cargo tank,
cofferdams and other spaces in the cargo area should be direct from the open deck
and designed such as to ensure complete inspection of those substances.
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.3 Access to double bottom spaces within the cargo area may be through a cargo
pump-room, pump-room, deep cofferdam, pipe tunnel or similar dry compartments with
their own direct access from open deck, subject to consideration of ventilation
aspects. Where cofferdams are provided over integral tanks, small trunks may be
used to penetrate the cofferdam.
3.3.2 For accesses defined in 3.3.1 and 4.1.8 through horizontal openings, hatches or
manholes, the dimensions should be sufficient to allow a person with a self-contained
air-breathing apparatus and protective equipment to ascend or descend any ladder without
obstruction and also to provide a clear opening to facilitate the hoisting of an injured
person from the bottom of the space. The minimum clear opening should be not less than
600 mm by 600 mm.
3.3.3 For accesses defined in 3.3.1 and 4.1.8 through vertical openings, or manholes
providing passage through the length and breadth of space, the minimum clear opening
should be not less than 600 mm by 800 mm at a height of not more than 600 mm from the
bottom shell or deck plating, unless gratings or other footholds are provided.
3.3.4 Smaller dimensions may be approved, if at least one main access defined in 3.3.1
and 4.1.8 has dimensions not less than those required in 3.3.2 and 3.3.3, respectively.
The main access should be identified clearly in an access plan.
3.3.5 Cargo pump-rooms should be so arranged as to ensure unrestricted access to all
valves necessary for cargo handling for a person wearing the required personal
protective equipment.