Fig:Making bulk carriers safer
Much of this work has concentrated
on the structural hull details, stresses experienced as the result of loading
and discharging cargoes, damage to structure and protective coatings
arising from discharging cargoes, poor maintenance and subsequent inadequate
inspection of the ship structure.
The outcome of this work has been
the introduction of a new Chapter XII of SOLAS covering bulk carrier ship
safety and enhanced survey procedures for bulk carriers. The chapter highlighting strengthening of hatch covers in the forward part of the ship ,structural requirement, adequacy of bow heights provide additional security against cargo damage, damage stability guideline and other requirements.
Fig: Bulk carrier encountering rough sea conditions
Guidance on early assessment of hull damage and possible abandonment
There have been cases in the past where ships carrying bulk cargoes have been lost due to a loss in
hull integrity. This, combined with the lack of prompt action, has resulted in lives being lost. Early
assessment of the situation is therefore imperative, combined with alerting a maritime rescue
coordination 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.
Heavy cargoes such as iron ore or heavy break bulk cargoes, such as steel, make a ship particularly
vulnerable. This is due to the relatively small volume of cargo compared to the large volume of
unoccupied space that provides the potential for large volumes of water to destroy the ship’s buoyancy,
stability or structural integrity.
Where flooding occurs, or is likely to occur, the master must rapidly assess the damage by being
alert to water ingress and its consequences. Such an assessment may be carried out by the
Unusual Motion or Attitude:
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. Signs may include:
Methods of Detection
- Unusual collections of water on decks maybe 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
- 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.
Early Readiness for Evacuation
- Hatch covers may be dislodged by pressure and/or sloshing from within a hold if flooding
occurs through side shell or bulkhead.
- Sudden pressurisation of compartments adjoining those that are damaged or flooded will
indicate failure of internal subdivision, most notably bulkheads.
- Spaces may be monitored, either using gauging or water ingress alarms. Forward store
spaces can also be monitored audibly using “talkback” telephones that may be fitted in
forward spaces. Anchor impacts and water in the space can be detected using telephones of
the type that remain active until switched off from the bridge.
- Hull Stress Monitors, where fitted, may be able to detect unexpected longitudinal hull girder
bending. Torsional stresses may also be detected through differential changes between port
and starboard strain gauges.
- Visual monitoring from the bridge using binoculars, where fitted, by closed circuit television,
can give indication of abnormal water on deck and local damage. However, assessment of
trim or freeboard using this method is difficult.
- Assessment of trim changes can, in certain conditions, be detected by noting the level of the
horizon, when visible, against a known reference point on the foremast.
- Draught and trim can be assessed using draught gauges. Changes are much more
discernible using this method than by visual means from above decks.
In the event of identifying, or even suspecting, that the ship may have sustained damage, the
ship’s personnel should immediately be called to their emergency stations. A HIGH PRIORITY
SHOULD BE PLACED ON PREPARING EQUIPMENT FOR EVACUATION. Abandonment should,
however, only be invoked on the spoken orders of the Master following assessment of the risk.
Contact with a Maritime Rescue Co-ordination Centre (MRCC) and the management office
should be made early if the Master has any suspicion that the ship is damaged. An URGENCY
(Pan-Pan) signal is justified and this should be upgraded to DISTRESS (Mayday) if the ship is
confirmed as damaged.
Masters should place a strong emphasis on evacuation training so that donning of protective
suits and lifejackets, launching of survival craft, and operation of EPIRBs and SARTs is a
familiar process to all ship’s personnel. Also included should be shutdown procedures for main
and auxiliary machinery, which can, if left running, hinder launching of survival craft.
Masters may wish to investigate any suspected water ingress more closely but preparations for
evacuating the ship should be made WITHOUT DELAY and concurrent with any investigation.
Remote methods of observation are preferable to sending personnel onto decks, particularly in
bad weather and / or at night. Deck floodlights should be used if necessary to try and identify
abnormalities. Detrimental effects on watch keeper’s night vision are of secondary importance
in such circumstances.
When a loss of hull integrity is known or suspected, personnel should not be sent onto decks
that are being regularly submerged or deeply awash. In such circumstances the ship should be
regarded as in imminent danger and priority should be given to preparations for evacuation.
Where water ingress alarms are fitted, full instructions must be posted by the alarm panel
which will normally be located on the bridge. All officers are to be made aware of the alarm
settings, correct operation and testing of this equipment.
Bulk carrier corrosion rates and preventive measures
Shipboard hazards & bulk carriers safety guideline
Health hazards for personnel working in a dusty condition onboard
Our detail pages illustrated many safety aspects of Bulk carrier
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Operation of sea going bulk carriers involved numerous hazards . Careful planning and exercising due caution for all critical shipboard matters are important . This site is a quick reference to international shipping community with guidance and information on the loading and discharging of modern bulk carriers so as to remain within the limitations as specified by the classification society.
- Indication of unusual motion or attitude of bulk carriers and risk management / evacuation
- Deterioration of ships structure and consequences of forward flooding
- Handling water ingress problems in bulk carrier, investigation and countermeasures
- Survival and safety procedure for bulk carriers
- How to avoid damage during cargo operation
- How to arrange repair of damage during cargo loading/unloading
- Bulk carrier corrosion rates and preventive measures
- Shipboard hazards & bulk carriers safety guideline
- Health hazards for personnel working in a dusty condition onboard
- Regulation of pumping system of bulk carriers
- Ships Confined area safe practice
- Causes of structural damage and countermeasures
It is vital to reduce the likelihood of over-stressing the ship's structure and also complying with all essential safety measures for a safe passage at sea. Our detail pages contain various bulk carrier related topics that might be useful for people working on board and those who working ashore in the terminal. For any remarks please
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