1 This guidance is to assist port State control
officers (PSCOs) in checking the structure as well as the operational
aspects of bulk carriers during port State control inspections.
2 In addition to this guidance, PSCOs should refer
to the following documents:
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.1 SOLAS chapter XII -
Additional safety measures for bulk carriers;
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.2
resolution A.862(20) -
Code of Practice for the Safe Loading and Unloading of Bulk Carriers;
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.3
resolution A.866(20) -
Guidance to ships' crews and terminal personnel for bulk carrier inspections;
and
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.4
resolution A.744(18) as
amended - Guidelines on the enhanced programme of inspections during
surveys of bulk carriers and oil tankers.
3 PSCOs are further invited to consult the following
IACS publications, if available:
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.1 Bulk Carriers: Guidelines for Surveys, Assessment
and Repair of Hull Structure;
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.2 Bulk Carriers: Guidance and Information on
Bulk Cargo Loading and Discharging to Reduce the Likelihood of Over-Stressing
the Hull Structure; and
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.3 Bulk Carriers - Handle With Care.
4 While checking the ship's documentation, PSCOs
should pay particular attention to the loading plan, cargo distribution
and loading/unloading sequences to ascertain that the ship is loaded
in accordance with the approved loading manual.
5 PSCOs should pay particular attention to the
tank top limitation, the bending moments and shearing forces as well
as the cargo distribution. Past experience shows that ships often
load in patterns not approved in the stability manual. For example,
on board a nine-hold bulk carrier, the approved stability manual often
has an annotation stating that holds 2, 4, 6 and 8 may be empty. This
implies that all even number holds must be empty at the same time.
In many cases, ship officers believe that such an annotation allows
for any combination of these holds to be empty, which is not the case.
6 PSCOs should remember that loading patterns
not included in the approved stability manual should not be accepted
since this might create excessive local stress to the ship's structure
regardless of the fact that the bending moments and shearing forces
are within the permissible values.
7 When it is established during a PSC inspection
that a ship loading pattern is not per the approved stability manuals,
the PSCO should request confirmation in the first instance by the
ship's officers, by the flag State administration, or the recognized
organization working on behalf of the flag State, that the proposed
loading plan/distribution is acceptable. In the event that a ship
is found non-compliant with the approved stability manuals during
unloading operations, the PSCO should inform the master and chief
officer that future loading should be within the limitation of the
approved stability manual.
8 Initially, a check of the survey report file
may identify possible suspect areas requiring inspection. The provisions
contained in resolution A.744(18) as
amended, require a specific survey programme which includes access
arrangements and, when necessary, the requirements for a close-up
survey and thickness measurements. A survey report file is required
to be held on board consisting of:
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.1 reports of structural surveys;
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.2 condition evaluation reports;
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.3 thickness measurement reports; and
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.4 survey planning document (or equivalent) containing
the following information:
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.4.1 main particulars;
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.4.2 plan of tanks and holds;
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.4.3 list of tanks and holds and usage, corrosion
protection and condition of coating;
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.4.4 corrosion risk in tanks; and
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.4.5 design risk of structures.
9 Ideally, inspections should be carried out by
a team of at least two PSCOs and include, at least, one person with
an in-depth knowledge of ship structures. In a loading port they should
be ready to board the ship on arrival. In a discharge port, information
on the likely discharge sequences should be obtained, where possible,
so that the inspection can be carried out when holds become available.
10 Access to the upper parts of holds is problematic.
Ladders may help and experience has shown that using binoculars along
with high-powered torches can assist in making an initial assessment
of the condition of inaccessible parts. If the condition of other
parts of the hold and the hull structure in general give rise to concern,
the flag State/recognized organization should be consulted to consider
the need for a more detailed survey.
11 The impression of hull maintenance and general
state on deck, the condition of items such as ladders, hatches, air
pipes, guardrails, visible evidence of previously effected repairs,
and the condition of deck machinery should influence the PSCO's decision
on whether to make the fullest possible examination of the hull.
12 Special attention should be given to areas
of high stress and bending moments, such as:
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.1 immediately forward of the engine-room bulkhead;
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.2 over the midships half-length; and
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.3 no.1 hold side shell framing and top and bottom
connections (panting region).
13 Particular attention should be given to areas
where fracturing, cracks, distortion or excessive wastage can occur.
These areas are illustrated in the diagrams in appendices 1 and 2footnote. The weather tight integrity of hatches
and closures is particularly important on ore carriers with minimal
reserve buoyancy.
14 Common defects are:
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.1 cracking at hatch corners;
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.2 plate panel buckling of cross deck strips and
stiffening structure;
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.3 cracking of hatch coamings;
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.4 cracking at intersection of the inner bottom
plating and the hopper plating;
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.5 grab and bulldozer damage to the side shell
frames lower brackets;
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.6 grab damage to the inner bottom plating, hopper
and lower stool plating;
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.7 cracking at side shell frame bracket toes;
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.8 both general and localized corrosion of side
shell frames and brackets;
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.9 cracking at fore and aft extremities of topside
tank structures;
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.10 corrosion within topside tanks; and
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.11 general corrosion and cracking of transverse
bulkheads.
15 If tanks or holds are to be inspected, the
PSCO should ensure it is safe to enter. The requirements of the Code
of Safe Practice for Solid Bulk Cargoes, Appendix F, apply. Additional
safeguards could include carrying personal devices capable of determining
the safety of tank atmospheres or employing the services of a chemist
to check the atmosphere.
16 Permanent seawater ballast tanks represent
one of the most likely problem areas and, if inspected, the following
aspects should be considered:
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.1 the paint condition in coated ballast tanks
and condition of anodes. In ballast tanks, rates of corrosion in the
order of 1mm per year may be encountered, depending on whether they
are coated or protected by anodes. In some ships, only the ullage
space is coated with the remainder protected by anodes. During empty
periods, this can result in corrosion on uncoated structures, which
remain wet;
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.2 in tanks used for ballast that may be subject
to variable depths of seawater, for example forepeak tanks, it is
often the case that there is little wastage top and bottom, but significant
wastage over central regions. Attention should be paid to longitudinal
stiffeners and brackets at the collision bulkhead to shell junction;
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.3 longitudinal shell stiffeners in dedicated
ballast tanks, particularly in areas adjacent to bulkheads and web
frames; and
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.4 underdeck longitudinals in ballast tanks. Wastage
is usually the most severe close to the deckhead. This may result
in the fillet welds, attaching longitudinals to the deck, being wasted
thus leading to detachment of the longitudinals and consequent buckling
of deck plates.
17 Where a fracture, which has not been caused
by contact damage, is found in the main hull structure on one side
of a ship, the corresponding structure on the opposite side should
be examined to see if a similar failure has occurred. Fractures of
this nature are of concern, especially where corrosion is associated
with the failure and may have been a contributing factor.
18 If relevant, the PSCO may check that the necessary
calculations have been made to ensure bending and shear stresses are
maintained within maximum limits both during loading/discharge and
the ensuing voyage. This is especially important where high density
cargoes are carried or where the loading/ballasting arrangement is
of a different configuration to that described in the ship's loading
manual.
19 In reaching any decision regarding a detention,
the PSCO should consider the seaworthiness and not the age of the
ship, making allowance for fair wear and tear over the minimum acceptable
scantlings. Where there is doubt, the classification society should
advise the accepted diminution rates of structural members. Damage
not affecting seaworthiness should not constitute grounds for judging
that a ship should be detained, nor should damage temporarily but
effectively repaired for a voyage to a port for permanent repairs.
However, in his assessment of the effect of damages, the PSCO should
have regard to the location of crew accommodation and whether the
damage substantially affects its habitability.
20 Any proposals from the flag State or classification
society should be considered carefully. Specification of repairs is
the responsibility of the classification society surveyor and need
only be agreed to by the PSCO. In the event that the proposals are
acceptable, care should be taken to ensure that the flag State and
classification society oversee the repairs and clear the ship before
a request to lift the detention is made.
21 Any proposal by the flag State to allow the
ship to make a single voyage to a repair yard should be in accordance
with chapter 4.7 of resolution A.787(19) as amended by resolution A.882(21) on Procedures for
port State control.