3.1.1 Hold spaces should be
segregated from machinery and boiler spaces, accommodation spaces,
service spaces and control stations, chain lockers, drinking and domestic
water tanks and from stores. Hold spaces should be located forward
of machinery spaces of category A, other than those deemed necessary
by the Administration for the safety or navigation of the ship.
3.1.2 Where cargo is carried
in a cargo containment system not requiring a secondary barrier, segregation
of hold spaces from spaces referred to in 3.1.1 or spaces either below or outboard of the hold spaces may
be effected by cofferdams, fuel oil tanks or a single gastight bulkhead
of all-welded construction forming an A-60 class division. A gastight
A-0 class division is satisfactory if there is no source of ignition
or fire hazard in the adjoining spaces.
3.1.3 Where cargo is carried
in a cargo containment system requiring a secondary barrier, segregation
of hold spaces from spaces referred to in 3.1.1 or spaces either below or outboard of the hold spaces which
contain a source of ignition or fire hazard should be effected by
cofferdams or fuel oil tanks. If there is no source of ignition or
fire hazard in the adjoining space, segregation may be by a single
A-0 class division which is gastight.
3.1.4 When cargo is carried
in a cargo containment system requiring a secondary barrier:
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.1 at temperatures below -10°C, hold spaces should be
segregated from the sea by a double bottom; and
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.2 at temperatures below -55°C, the ship should also
have a longitudinal bulkhead forming side tanks.
3.1.5 Any piping system which
may contain cargo or cargo vapour should:
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3.1.5.1 be segregated from other piping systems,
except where interconnections are required for cargo-related operations such as
purging, gas-freeing or inerting. In such cases, precautions should be taken to
ensure that cargo or cargo vapour cannot enter such other piping systems through
the interconnections;
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3.1.5.2 except as provided in chapter
16, not pass through any accommodation space, service space or control
station or through a machinery space other than a cargo pump-room or cargo
compressor space;
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3.1.5.3 be connected into the cargo containment
system directly from the open deck except that pipes installed in a vertical
trunkway or equivalent may be used to traverse void spaces above a cargo
containment system and except that pipes for drainage, venting or purging may
traverse cofferdams;
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3.1.5.4 except for bow or stern loading and unloading
arrangement in accordance with 3.8 and
emergency cargo jettisoning piping systems in accordance with 3.1.6, and except in accordance with chapter
16, be located in the cargo area above the open deck; and
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3.1.5.5 except for thwartship shore connection piping
not subject to internal pressure at sea or emergency cargo jettisoning piping
systems, be located inboard of the transverse tank location requirements of 2.6.1.
3.1.6 Any emergency cargo jettisoning
piping system should comply with 3.1.5 as
appropriate and may be led aft externally to accommodation spaces,
service spaces or control stations or machinery spaces, but should
not pass through them. If an emergency cargo jettisoning piping system
is permanently installed a suitable means of isolation from the cargo
piping should be provided within the cargo area.
3.1.7 Arrangements should be
made for sealing the weather decks in way of openings for cargo containment
systems.