GUIDELINES ON EARLY ASSESSMENT OF HULL DAMAGE AND
POSSIBLE NEED FOR ABANDONMENT OF BULK CARRIERS
1 The Maritime Safety Committee, at its seventy-sixth session (2 to 13 December 2002),
considered recommendations for decision-making emanating from various formal safety assessment
(FSA) studies on bulk carrier safety. In particular, the Committee agreed that a circular should be
prepared addressing bulk carriers which may not withstand flooding of any one cargo hold and
containing information on the action to be taken in case of flooding of such holds, making sure that
the professional judgement of the master is not undermined.
2 The Committee, at its seventy-ninth session (1 to 10 December 2004), having considered the
recommendations made by the Sub-Committee on Ship Design and Equipment at its forty-sixth
session, the Sub-Committee on Safety of Navigation at its forty-ninth and fiftieth sessions and the
Sub-Committee on Standards of Training and Watchkeeping at its thirty-fifth session, approved
Guidelines on early assessment of hull damage and possible need for abandonment of bulk carriers,
as set out in the annex. Some common causes of hull damage are contained in the Appendix to the
annex.
3 Member Governments are invited to urge companies, as defined in the ISM Code, that
operate bulk carriers flying their flag, to issue ship specific guidance, based on the annexed
Guidelines, to the masters of such bulk carriers with a view to improving the precautionary measures
and procedures for emergencies on board their ships. This ship specific guidance should be brought
to the attention of all crew members during familiarization training.
***
MSC/Circ.1143
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ANNEX
GUIDELINES ON EARLY ASSESSMENT OF HULL DAMAGE AND
POSSIBLE NEED FOR ABANDONMENT OF BULK CARRIERS
1 Provoked by the disappearance and loss of a number of bulk carriers from mid 1970s
onwards the international shipping community has grown increasingly concerned that such ships are
particularly vulnerable to rapid loss. Consequently, IMO has been taking action over the years to
address this problem and to find appropriate solutions. Among such actions, the Organization has
adopted amendments to the 1974 SOLAS Convention, by introducing chapter XII in 1997 (amended
in 2002), and other related provisions in chapter II-1, and has also amended the Guidelines on the
enhanced programme of inspections during surveys of bulk carriers and oil tankers
(resolution A.744(18)) on several occasions. More recently, a number of formal safety assessment
(FSA) studies on bulk carrier safety have been carried out. From these studies, the Maritime Safety
Committee of IMO concluded at its seventy-sixth session in December 2002 that bulk carriers do
deserve continued special attention and a number of measures were approved to address the issues
identified, both structural and operational.
2 Records of bulk carrier losses indicated, in a large proportion of the cases studied, that ship.s
masters often appeared to be unaware of the imminent danger they were in. Many lost their lives
together with the other seafarers on board as a consequence. Ship losses were frequently so rapid
that the ship did not have time to send a distress signal.
3 The records studied show that in the event of loss of hull integrity, in many cases, bulk
carriers should be evacuated as quickly as possible. EARLY ASSESSMENT OF THE SITUATION
IS THEREFORE IMPERATIVE, COMBINED WITH ALERTING A MARITIME RESCUE
CO-ORDINATION CENTRE, ALERTING ALL PERSONNEL ONBOARD AND MAKING
PREPARATIONS FOR EVACUATION. This is of particular importance for single skin bulk
carriers which may not be capable of withstanding flooding of any cargo hold.
4 Companies should consider the following advice carefully with a view to improving their
own precautionary measures and procedures for emergencies. The advice applies equally to ships
other than bulk carriers when carrying dense cargoes.
Heavy cargoes
5 In most cases in which bulk carriers have been lost, heavy cargoes such as iron and other
dense ores are a common factor. Ships are also vulnerable when carrying certain break-bulk cargoes
such as steel products. This could include other ship types. The small volume taken up by the cargo
in the ships. holds results in a large unoccupied space. This provides potential in a flooding scenario
for large volumes of water to rapidly destroy the ship.s residual buoyancy and, in the case of smaller
vessels, its stability. Larger vessels are also highly susceptible to structural failure due to increases
of weights caused by the influx of water.
6 Heavy cargoes place high loads on the structure, and structural failure is therefore more
probable when subjected to the additional forces associated with flooding.
MSC/Circ.1143
ANNEX
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Structure
7 Deterioration of structure through corrosion, fatigue and damage is identified as a principal
factor in the loss of many bulk carriers. Failing to identify such deterioration may lead to sudden and
unexpected failure. Bulk carrier crews may be unaware of the vulnerability of these vessel types.
The consequential loss of a ship carrying heavy cargo can be expected to be very rapid, should a
major failure occur.
Forward flooding
8 Spaces forward of the collision bulkhead will, in the event of flooding, significantly affect the
trim of the ship and reduce freeboard at the bow. In extreme weather this further threatens the ship
as green seas come inboard and impact on hatch covers and other fittings that protect the water or
weathertight integrity of the ship. Shell plating in the region of the bow protects the fore peak tank
and other spaces as do air pipes and ventilators. If any of them are damaged the ship.s ability to
resist further escalation of flooding is compromised.
Early assessment
9 When it occurs or is likely to occur, masters should quickly assess damage to their ships by
being alert to water ingress and its consequences. The following guidelines are given to assist them
in this assessment.
Unusual motion or attitude
10 If a ship takes on an unusual trim or heel, or if her motions become changed, breach of the
hull envelope should be suspected immediately:
- Unusual collections of water on decks may be indicating trim or heel abnormality.
- Sudden changes of heel or trim will indicate flooding or in smaller ships with lighter
cargoes it may indicate cargo shift.
- Jerky lateral motions can be indicative of large scale sloshing as would be the case if a
hold were flooded.
- On smaller ships, slowing of the ship.s roll period may indicate excessive water within
the hull - a serious threat to stability. Ships fitted with GM meters should be able to
identify any unexpected changes in GM.
- Increases of water boarding forward decks may indicate flooding of a forward
compartment. Trim and freeboard changes are notoriously difficult to assess from an
after bridge.
11
Methods of detection - Hatch covers may be dislodged by pressure and/or sloshing from within a hold if
flooding occurs through side shell or bulkhead.
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