(Paragraph 3.7.2.2 applies to ships constructed on
or after 1 July 2002)
3.7.1.1 Where cargo is carried
in a cargo containment system not requiring a secondary barrier, hold
spaces should be provided with suitable drainage arrangements not
connected with the machinery space. Means of detecting any leakage
should be provided.
3.7.1.2 Where there is a
secondary barrier, suitable drainage arrangements for dealing with
any leakage into the hold or insulation spaces through adjacent ship
structure should be provided. The suction should not be led to pumps
inside the machinery space. Means of detecting such leakage should
be provided.
3.7.2.1 The hold or interbarrier
spaces of Type A independent tank ships should be provided with a
drainage system suitable for handling liquid cargo in the event of
cargo tank leakage or rupture. Such arrangements should provide for
the return of any cargo leakage to the liquid cargo piping.
3.7.2.2 Arrangements referred
to in 3.7.2.1 should be provided
with a removable spool piece.
3.7.3 In case of internal insulation
tanks, means of detecting leakage and drainage arrangements are not
required for interbarrier spaces and spaces between the secondary
barrier and the inner hull or independent tank structure which are
completely filled by insulation material complying with 4.9.7.2.
3.7.4 Ballast spaces, including
wet duct keels used as ballast piping, fuel-oil tanks and gas-safe
spaces may be connected to pumps in the machinery spaces. Dry duct
keels with ballast piping passing through, may be connected to pumps
in the machinery spaces, provided the connections are led directly
to the pumps and the discharge from the pumps lead directly overboard
with no valves or manifolds in either line which could connect the
line from the duct keel to lines serving gas-safe spaces. Pump vents
should not be open to machinery spaces.