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Sunday, March 17, 2013

BULK CARRIER SAFETY

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Bulk Carrier Safety
Bulk carriers were developed in the 1950s to carry large quantities of non-packed commodities such as grains, coal and iron ore. Some 5,000 bulk carriers trade around the world, providing a crucial service to world commodities' transportation.
Bulk carrier operators must be aware of the specific safety concerns related to this type of ship. Loading of cargo must be done carefully, to ensure cargo cannot shift during a voyage leading to stability problems. Large hatch covers must be watertight and secure.Following a spate of losses of bulk carriers in the early 1990s, IMO in November 1997 adopted new regulations in SOLAS containing specific safety requirements for bulk carriers, Chapter XII - Additional Safety Measures for Bulk Carriers. In the same month, the 20th Assembly of IMO adopted the "BLU Code" - the Code of Practice for the safe unloading and loading of bulk carriers (resolution A.862(20).
Following the 1998 publication of the report into the sinking of the bulk carrier Derbyshire, the Maritime Safety Commitee (MSC) initiated a further review of bulk carrier safety, involving the use of Formal Safety Assessment (FSA) studies to help assess what further changes in regulations might be needed.
In December 2002, at its 76th session, the MSC adopted amendments to chapter XII and also agreed to a number of recommendations to further improve bulk carrier safety.
In December 2004, the MSC adopted a new text for SOLAS chapter XII, incorporating revisions to some regulations and new requirements relating to double-side skin bulk carriers. These amendments are expected to enter into force on 1 July 2006.
SOLAS Chapter XII - Additional Safety Measures for Bulk Carriers
The new chapter XII to SOLAS was adopted by a conference held in November 1997 and it entered into force on : 1 July 1999.
The Conference adopted a Protocol adding a new Chapter XII to the Convention entitled Additional Safety Measures for Bulk Carriers.
The regulations state that all new bulk carriers 150 metres or more in length (built after 1 July 1999) carrying cargoes with a density of 1,000 kg/m3 and above should have sufficient strength to withstand flooding of any one cargo hold, taking into account dynamic effects resulting from presence of water in the hold and taking into account the recommendations adopted by IMO.
For existing ships (built before 1 July 1999) carrying bulk cargoes with a density of 1,780 kg/m3 and above, the transverse watertight bulkhead between the two foremost cargo holds and the double bottom of the foremost cargo hold should have sufficient strength to withstand flooding and the related dynamic effects in the foremost cargo hold.
Cargoes with a density of 1,780 kg/m3 and above (heavy cargoes) include iron ore, pig iron, steel, bauxite and cement. Lighter cargoes, but with a density of more than 1,000 kg/m3, include grains such as wheat and rice, and timber.
The amendments take into account a study into bulk carrier survivability carried out by the International Association of Classification Societies (IACS) at the request of IMO. IACS found that if a ship is flooded in the forward hold, the bulkhead between the two foremost holds may not be able to withstand the pressure that results from the sloshing mixture of cargo and water, especially if the ship is loaded in alternate holds with high density cargoes (such as iron ore). If the bulkhead between one hold and the next collapses, progressive flooding could rapidly occur throughout the length of the ship and the vessel would sink in a matter of minutes.
IACS concluded that the most vulnerable areas are the bulkhead between numbers one and two holds at the forward end of the vessel and the double bottom of the ship at this location. During special surveys of ships, particular attention should be paid to these areas and, where necessary, reinforcements should be carried out.
The criteria and formulae used to assess whether a ship currently meets the new requirements, for example in terms of the thickness of the steel used for bulkhead structures, or whether reinforcement is necessary, are laid out in IMO standards adopted by the 1997 Conference.
Under Chapter XII, surveyors can take into account restrictions on the cargo carried in considering the need for, and the extent of, strengthening of the transverse watertight bulkhead or double bottom. When restrictions on cargoes are imposed, the bulk carrier should be permanently marked with a solid triangle on its side shell. The date of application of the new Chapter to existing bulk carriers depends on their age. Bulk carriers which are 20 years old and over on 1 July 1999 have to comply by the date of the first intermediate or periodic survey after that date, whichever is sooner. Bulk carriers aged 15-20 years must comply by the first periodical survey after 1 July 1999, but not later than 1 July 2002. Bulk carriers less than 15 years old must comply by the date of the first periodical survey after the ship reaches 15 years of age, but not later than the date on which the ship reaches 17 years of age.
December 2002 SOLAS amendments relating to bulk carrier safety
The MSC at its 76th session in December 2002 adopted amendments to chapter XII (Additional Safety Measures for Bulk Carriers) of the International Convention for the Safety of Life at Sea (SOLAS), 1974, as amended to require the fitting of high level alarms and level monitoring systems on all bulk carriers, in order to detect water ingress.
The recommendation for the fitting of such alarms was first highlighted during the meeting of the Working Group on Bulk Carrier Safety held during the MSC's 74th session in December 2001, following on from recommendations of the United Kingdom Report of the re-opened formal investigation into the loss of the Derbyshire.
The new regulation XII/12 on Hold, ballast and dry space water level detectors will require the fitting of such alarms on all bulk carriers regardless of their date of construction. The requirement is expected to enter into force on 1 July 2004, under the tacit acceptance procedure.
In addition, a new regulation XII/13 on Availability of pumping systems would require the means for draining and pumping dry space bilges and ballast tanks any part of which is located forward of the collision bulkhead to be capable of being brought into operation from a readily accessible enclosed space.
A further regulation affecting bulk carriers was also adopted: Access to spaces in cargo areas of oil tankers and bulk carriers. The new regulation II-1/3-6 in SOLAS chapter II-1 (Construction - structure, subdivision and stability, machinery and electrical installations), Part B (Subdivision and stability), is intended to ensure that vessels can be properly inspected throughout their lifespan, by designing and building the ship to provide suitable means for access. Associated Technical provisions for means of access for inspections, also adopted, are mandatory under the new regulation.
December 2004 - revised SOLAS chapter XII adopted

The MSC at its 79th session in December 2004 adopted a new text for SOLAS chapter XII (Additional safety measures for bulk carriers), incorporating revisions to some regulations and new requirements relating to double-side skin bulk carriers. The amendments are expected to enter into force on 1 July 2006.
The amendments include the addition of a new regulation 14 on restrictions from sailing with any hold empty and requirements for double-side skin construction as an optional alternative to single-side skin construction. The option of double-side skin construction will apply to new bulk carriers of 150m in length and over, carrying solid bulk cargoes having a density of 1,000 kg/m3 and above.
The MSC also adopted standards and criteria for side structures of bulk carriers of single-side skin construction and standards for owners' inspections and maintenance of bulk carrier hatch covers.
Free-fall lifeboats on bulk carriers
The MSC at its 79th session in December 2004 also adopted an amendment to regulation 31 in SOLAS chapter III (Life-saving appliances and arrangements) to make mandatory the carriage of free-fall lifeboats on bulk carriers.
Further information
Focus on IMO - IMO and the safety of bulk carriers - 1999
This paper reviews the specific safety issues realting to bulk carriers and the background to the adoption of SOLAS chapter XII.

BLU Code, 1998 Edition
CODE OF PRACTICE FOR THE SAFE LOADING AND UNLOADING OF BULK CARRIERS (BLU CODE), 1998 Edition
Being concerned about the continued loss of ships carrying solid bulk cargoes, sometimes without a trace, and the heavy loss of life incurred, and recognizing that a number of accidents have occurred as a result of improper loading and unloading of bulk carriers, the Sub-Committee on Dangerous Goods, Solid Cargoes and Containers (DSC) at its first session (February 1996) developed a draft code of practice for the safe loading and unloading of bulk carriers, with the aim of preventing such accidents.
The resulting Code of Practice for the Safe Loading and Unloading of Bulk Carriers (BLU Code) was approved by the MSC at its 68th session (June 1997) and adopted by the Assembly at its 20th session (November 1997) by resolution A.862(20).
The BLU Code, which provides guidance to masters of bulk carriers, terminal operators and other parties concerned with the safe handling, loading and unloading of solid bulk cargoes, is also linked to regulation VI/7 of the 1974 SOLAS Convention, as amended by resolution MSC.47(66).




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