IMSBC CODE

Danger of cargo liquefaction – Bulk Carriers

International Maritime Solid Bulk Cargo (IMSBC) Code categorizes cargoes into three groups, A, B & C:

A = cargoes which may liquefy if shipped at a moisture content in excess of their transportable moisture limit

B = cargoes which possess a chemical hazard which could give rise to a dangerous situation on a ship.

C = consists of cargoes which are neither liable to liquefy (Group A) nor to possess chemical hazards (Group B).

Liquefaction property of group A cargo is a major concern on safety of ship and its crew. In 2010 vessels Jian Fu Star, Nasco Diamond, Hong Wei and Vinalines Queen sank resulting in total loss of 67 lives at sea. The cargo carried by these four ill-fated vessels was nickel ore.

When liquefaction takes place vessel at sea may experience cargo shifting resulting in sudden loss of stability and capsizing.

When does liquefaction occur? Liquefaction takes place if the moisture content in cargo is above the Transportable Moisture Limit (TML). Since Nickel ore is not listed by name in IMSBC Code the carriage of nickel ore must be within the scope of section 1.3 “Cargoes not listed in this Code”

Recommendations are submitted to Maritime Safety Committee for implementing binding rules for engagement of National Competent Authority together with qualified laboratories for assessment of moisture content, TML to ensure cargoes which may liquefy is not loaded if moisture content is above TML.

Quote from China’s submission to Maritime Safety Committee (MSC89)

“China, as the country of nationality of the 45 seafarers [who lost their lives], carried out the investigation immediately after the accidents. In view of the fact that the subject ships had sunk and the difficulty to obtain cargo samples from the port of loading, the investigation was mainly based on the interviews with the surviving seafarers.

According to the evidence available, the direct cause of these accidents was the loss of stability as a result of cargo liquefaction and shifting in bad weather. However, the cargo documentation provided to the masters indicated that the moisture content of the cargo samples was lower than the Transportable Moisture Limit (TML)”.

Japan: ClassNK – New Edition of “Guidelines for the Safe Carriage of Nickel Ore” (worldmaritimenews.com)
ClassNK Revises Guidelines Following Loss of MV Vinalines Queen (gcaptain.com)
Imsbc Code – Shipper’s Declaration

IMSBC CODE – SHIPPER’S DECLARATION

Before loading of Solid Bulk Cargo the shipper must furnish information to the master or his representative about the cargo sufficiently in advance of loading to enable the precautions which may be necessary for proper stowage and safe carriage of the cargo to be put into effect.

Sample editable form is attached here.IMSBC DECLARATION

Angle of Repose

Bulk granular materials when poured on a flat surface will create a conical pile. The internal angle between the surface of the pile and the horizontal surface is called as ‘angle of repose’. Angle of repose is depended on the density, surface area, and the shapes of the particle also the coefficient of friction.

Antlion larvae’s sand pit works on critical angle of repose to catch its prey, see below image

IMSBC Code defines angle of repose as the maximum slope angle of non-cohesive (i.e., free-flowing) granular material. It is measured as the angle between a horizontal plane and the cone slope of such material.

Angle of repose of UN 1942 AMMONIUM NITRATE is 27 deg to 42 deg

MHB in IMSBC Code

IMSBC Code defines MHB ( Materials hazardous only in bulk ) as materials which may possess chemical hazards when carried in bulk other than materials classified as dangerous goods in the IMDG Code.

Below are MHBs listed in IMSBC Code with description and their hazardous nature.

BROWN COAL BRIQUETTES

Brown Coal (Lignite) Briquettes are manufactured by pressing dried brown coal particles into compressed blocks.

Briquettes are easily ignited, liable to spontaneous combustion and will deplete oxygen in cargo space.
CHARCOAL

Wood burnt at a high temperature with as little exposure to air as possible. Very dusty, light cargo. Can absorb moisture to about 18 to 70% of its weight. Black powder or granules.

May ignite spontaneously. Contact with water may cause self-heating. Liable to cause oxygen depletion in the cargo space. Hot charcoal screenings in excess of 55oC should not be loaded.

COAL

Coal (bituminous and anthracite) is a natural, solid, combustible material consisting of amorphous carbon and hydrocarbons.

Coal may create flammable atmospheres, may heat spontaneously, may deplete the oxygen concentration, may corrode metal structures. Can liquefy if predominantly fine 75% less than 5 mm coal.

DIRECT REDUCED IRON (A)

A metallic grey colloid material emanating from a densification process whereby the direct reduced iron (DRI) feed material is at a temperature greater than 650oC at time of moulding and has a density greater than 5.0 g/cm3. Fines (under 4 mm) not to exceed 5%.

Material may slowly evolve hydrogen after contact with water. Temporary self-heating of about 30oC may be expected after material handling in bulk.

This cargo is non-combustible or has a low fire-risk.

DIRECT REDUCED IRON (B)

Direct Reduced Iron (DRI) (B) is a metallic material of a manufacturing process formed by the reduction (removal of oxygen) of iron oxide at temperatures below the fusion point of iron.

Cold-moulded briquettes should be defined as those which have been moulded at a temperature of under 650oC or which have a density of less than 5.0 g/cm3.

DRI may react with water and air to produce hydrogen and heat. The heat produced may cause ignition. Oxygen in an enclosed space may be depleted.

FERROPHOSPHORUS

An alloy of iron and phosphorus used in the steel industry

May evolve flammable and toxic gases (e.g. phosphine) in contact with water.

This cargo is non-combustible or has a low fire-risk.

FERROSILICON

25% to 30% silicon, or 90% or more with silicon (including briquettes)

Ferrosilicon is an extremely heavy cargo.

In contact with moisture or water it may evolve hydrogen, a flammable gas which may form explosive mixtures with air and may, under similar circumstances, produce phosphine and arsine, which are highly toxic gases.

This cargo is non-combustible or has a low fire-risk.

FLUORSPAR

Yellow, green or purple crystals. Coarse dust.

This material may liquefy if shipped at moisture content in excess of their Transportable moisture limit. See section 7 of the Code. Harmful and irritating by dust inhalation.

LIME (UNSLAKED)

White or greyish-white in colour.

Unslaked lime combines with water to form calcium hydroxide (hydrated lime) or magnesium hydroxide. This reaction develops a great deal of heat which may be sufficient to cause ignition of nearby combustible materials. This is not combustible or has a low fire-risk corrosive to eyes and mucous membranes.

This cargo is non-combustible or has a low fire-risk.

LINTED COTTON SEED

Cottonseed with short cotton fibres adhering to the kernel after approximately 90% – 98% of the cotton has been removed by machine.

May self-heat and deplete oxygen in cargo space.

MAGNESIA (UNSLAKED)

Combines with water to form magnesium hydroxide with an expansion in volume and a release of heat. May ignite materials with low ignition temperatures. Similar to LIME (UNSLAKED) but is less reactive. Corrosive to eyes and mucous membranes.

This cargo is non-combustible or has a low fire-risk.

METAL SULPHIDE CONCENTRATES

Mineral concentrates are refined ores in which the valuable components have been enriched by eliminating the bulk of waste materials. Generally the particle size is small although agglomerates sometimes exist in concentrates which have not been freshly produced

.The most common concentrates in this category are: zinc concentrates, lead concentrates, copper concentrates and low grade middling concentrates.

Some sulphide concentrates are liable to oxidation and may have a tendency to self-heat, with associated oxygen depletion and emission of toxic fumes. Some materials may present corrosion problems.

When a Metal Sulphide Concentrate is considered as presenting a low fire-risk, the carriage of such cargo on a ship not fitted with a fixed gas fire extinguishing system should be subject to the Administration’s authorization as provided by SOLAS regulation II-2/10.7.1.4.

PEAT MOSS

Surface mined from mires, bogs, fens, muskeg and swamps. Types include moss peat, sedge peat and grass peat. Physical properties depend on organic matter, water and air content, botanical decomposition and degree of decomposition.

May range from a highly fibrous cohesive mass of plant remains which when squeezed in its natural state exudes clear to slightly coloured water, to a well decomposed, largely amorphous material with little or no separation of liquid from solids when squeezed.

Typically air-dried peat has low density, high compressibility and high water content; in its natural state it can hold 90 percent or more of water by weight of water when saturated.

Oxygen depletion and an increase in carbon dioxide in cargo and adjacent spaces.

Risk of dust explosion when loading. Caution should be exercised when walking or landing heavy machinery on the surface of uncompressed Peat Moss.

Peat Moss having a moisture content of more than 80% by weight should only be carried on specially fitted or constructed ships Dust may cause eye, nose and respiratory irritation.

PETROLEUM COKE (calcined or uncalcined)

Black, finely divided residue from petroleum refining in the form of powder and small pieces.

Uncalcined petroleum coke is liable to heat and ignite spontaneously when not loaded and transported under the provisions of this entry.

This cargo is non-combustible or has a low fire-risk.

PITCH PRILL

Pitch Prill is made from tar produced during the coking of coal. It is black with a distinctive odour. It is extruded into its characteristic pencil shape to make handling easier.

Cargo softens between 40ºC to 50ºC. Melting point: 105ºC to 107ºC

Melts when heated. Combustible, burns with a dense black smoke. Dust may cause skin and eye irritation. Normally this cargo has a low fire-risk. However powder of the cargo is easy to ignite and may cause fire and explosion. Special care should be taken for preventing fire during loading or discharging.

PYRITES, CALCINED (Calcined Pyrites)

Dust to fines, Calcined Pyrites is the residual product from the chemical industry where all types of metal sulphides are either used for the production of sulphuric acid or are processed to recover the elemental metals – copper, lead, zinc, etc. The acidity of the residue can be considerable, in particular, in the presence of water or moist air, where pH values between 1.3 and 2.1 are frequently noted.

Highly corrosive to steel when wet. Inhalation of dust is irritating and harmful. Cargo may

liquefy. This cargo is non-combustible or has a low fire-risk.

SAWDUST

Fine particles of wood.

Spontaneous combustion if not clean, dry and free from oil. Liable to cause oxygen depletion within the cargo space.

SILICOMANGANESE

Silicomanganese is an extremely heavy cargo, silvery metallic material with a grey oxide coating.

HAZARD

In contact with water may evolve hydrogen, a flammable gas that may form explosive mixtures with air and may, under similar conditions produce phosphine and arsine, which are highly toxic gases.

Cargo is liable to reduce oxygen content in a cargo space.

This cargo is non-combustible or has a low fire-risk

TANKAGE

The dried sweeping of animal matter from slaughterhouse floors. Very dusty.

Subject to spontaneous heating and possible ignition. Possibly infectious.

VANADIUM ORE

Dust may be toxic.

This cargo is non-combustible or has a low fire-risk

WOODCHIPS

Natural timber mechanically chipped into the approximate size of a business card.

This material possesses a chemical hazard. Some shipments may be subject to oxidation leading to depletion of oxygen and increase of carbon dioxide in cargo and adjacent spaces.

With moisture content of 15% or more this cargo has a low fire-risk. As the moisture content decreases the fire risk increases. When dry, woodchips can be easily ignited by external sources; are readily combustible and can ignite by friction.

WOOD PELLETS

The Wood Pellets are light blond to chocolate brown in colour; very hard and cannot be easily squashed. Wood Pellets have a typical specific density between 1,100 to 1,700 kg/m3 and a bulk density of 600 to 750 kg/m3. Wood Pellets are made of sawdust, planer shavings and other wood waste such as bark coming out of the lumber manufacturing processes. Normally there are no additives or binders blended into the pellet, unless specified. The raw material is fragmented dried and extruded into pellet form. The raw material is compressed approximately 3.5 times and the finished Wood Pellets typically have a moisture content of 4 to 8%. Wood Pellets are used as a fuel in district heating and electrical power generation as well as a fuel for small space heaters such as stoves and fireplaces.

Wood Pellets are also used as animal bedding due to the absorption characteristics. Such Wood Pellets typically have a moisture content of 8 to 10%.

Shipments may be subject to oxidation leading to depletion of oxygen and increase of

carbon monoxide and carbon dioxide in cargo and communicating spaces.

Swelling if exposed to moisture. Wood Pellets may ferment over time if moisture content is over 15% leading to generation of asphyxiating and flammable gases which may cause spontaneous combustion.

Handling of Wood Pellets may cause dust to develop. Risk of explosion at high dust concentration.

WOOD PULP PELLETS

The pellets are brown in colour; very hard and cannot be easily squashed. They are light and are about half the size of a bottle cork. The pellets are made of compacted woodchips.

This cargo possesses a chemical hazard. Some shipments may be subject to oxidation leading to depletion of oxygen and increase of carbon dioxide in cargo and adjacent spaces. With moisture content of 15% or more this cargo has a low fire-risk. As the moisture content decreases, the fire risk increases.

IMSBC Code Training (shashikallada.wordpress.com)
Another Hazardous Cargo, Another 22 Seafarers Lost at Sea (gcaptain.com)

IMSBC Code Training

International Maritime Solid Bulk Cargoes , IMSBC, Code supersede Safe Practice for Solid Bulk Cargoes. IMSBC Code became mandatory from 1st January 2011.

Annex 4 of IMSBC Code is pertaining to training of terminal personnel involved in loading or unloading of bulk carriers

Below is quoted from Annex 4 of IMSBC code

— quote —

Loader/unloader operator training should include:
1. The general hazards of loading and/or unloading Bulk Carriers (ref. BLU Code (Code of Practice for the Safe Loading and Unloading of Bulk Carriers) and BC Code (Code of Safe Practice for Solid Bulk Cargoes))

2. The dangerous effect improper loading and/or unloading can have on a ship.
Practical aspects to be included in the training should include:

The BLU Code so that they understand and appreciate both the obligations it places on their terminal, and the limitations of the ships the terminal personnel are loading and/or unloading.

The correct operating instructions for the ship loader or unloader they are operating.

A basic understanding of the mechanical and electrical components of the loader and/or unloader such as travel drives, braking arrangements, ropes and rope care, grab/trolley winches, conveyors, operating and wind limits, storm anchoring.

Emergency procedures such as fire on ship, terminal, or loader and/or unloader; mooring incidents, emergency stops.

The correct techniques and patterns to be used to load or unload a ship, depending on the type of and number of loaders or unloaders being used.

To load a ship:
Loader operators should have an appropriate understanding of how to:

Distribute the cargo in each hold in accordance with the agreed cargo plan to ensure the ship remains upright, and is neither stressed nor twisted.

Ensure no hold is overloaded or overfilled, and that the ship can be safely trimmed on completion.

Ensure loading efficiency is maximized, as per the agreed loading/deballasting plan.

Ensure safety and environmental protection procedures are followed.

Ensure that good communications are maintained between the loader operator and the designated ships officer, and between master and terminal representative.

To unload a ship:
Unloader operators should have an appropriate understanding of how to:
Unload the cargo from each hold in accordance with the agreed unloading plan to ensure that the ship remains upright and is not stressed or twisted.

Remove the cargo from the holds by either grab or continuous unloader in a manner that minimizes the risk of damage to the ships structure.

Ensure that good communications are aintained between the unloader operator and the designated ships officer, and between master and terminal representative.

Assess the risks arising from cargo sticking in frames and on hopper sides and facilitate, if possible, its safe removal without risk to the safety of terminal personnel and ships crew members, or risk of damage to ship.

Terminal representative training
The terminal representative should:

1. Have a thorough understanding of the underlying principles related to the loading and/or unloading of bulk carriers as described in the BLU Code.

2. Know how to implement all aspects of the BLU Code.

3. Understand and manage the ship/shore interface in relation to the operations and limitations of the terminal, its cargo handling equipment and procedures, the planning, control and monitoring of cargoes, relevant properties of the cargoes being handled, berthing/mooring operations and emergency procedures.

The training, assessment and certification of trainees should be carried out by competent persons within the framework of existing training standards and national health and safety legislation

—unquote —

IMSBC Code

The International Maritime Organization‘s convention of Safety of Life at Sea (SOLAS) 1974, as amended, deals with various safety aspects for sea going vessels including carriage of cargo.

SOLAS chapter VI part A & B pertains to mandatory provisions governing the carriage of solid bulk cargoes and Chapter VII part B the mandatory provisions of carriage of dangerous goods in solid form in bulk. The provisions of these chapters are amplified in Maritime Solid Bulk Cargoes Code (IMSBC Code). SOLAS Part A of chapter VII deals with packaged dangerous cargo which is amplified in International Maritime Dangerous Goods Code (IMDG Code).

IMSBC Code became mandatory from 1^st January 2011.

Table of Contents in IMSBC Code

Foreword
Section 1 General provisions and definitions
Section 2 General loading, carriage and unloading precautions
Section 3 Safety of personnel and ship
Section 4 Assessment of acceptability of consignments for safe shipment
Section 5 Trimming procedures
Section 6 Methods of determining angle of repose
Section 7 Cargoes that may liquefy
Section 8 Test procedures for cargoes that may liquefy
Section 9 Materials possessing chemical hazards
Section 10 Carriage of solid bulk wastes
Section 11 Security provisions
Section 12 Stowage factor conversion tables
Section 13 References
Appendix 1 Individual schedules of solid bulk cargoes
Appendix 2 Laboratory test procedures, associated apparatus and standards
Appendix 3 Properties of solid bulk cargoes
Appendix 4 Index of solid bulk cargoes

Considering safety solid bulk cargoes are divided into Group A, B & C

Group A
consists of cargoes which may liquefy if shipped at moisture content in excess of their transportable moisture limit.

Group B
consists of cargoes which possess a chemical hazard which could give rise to a dangerous situation on a ship.

Group C
consists of cargoes which are neither liable to liquefy (Group A) nor to possess chemical hazards (Group B).

Hazard classification

Dangerous goods are classified in accordance with chapter 2 of the IMDG Code.

Class 4.1: Flammable solids: The materials in this class are readily combustible solids and solids which may cause fire through friction.

Class 4.2: Substances liable to spontaneous combustion: The materials in this class are materials, other than pyrophoric materials, which, in contact with air without energy supply, are liable to self-heating.

Class 4.3: Substances which, in contact with water, emit flammable gases: The materials in this class are solids which, by interaction with water, are liable to become spontaneously flammable or to give off flammable gases in dangerous quantities.

Class 5.1: Oxidizing substances: The materials in this class are materials while in themselves not necessarily combustible, may, generally by yielding oxygen cause, or contribute to, the combustion of other material.

Class 6.1: Toxic substances: The materials in this class are materials liable either to cause death or serious injury or to harm human health if swallowed or inhaled, or by skin contact.

Class 7: Radioactive materials: The materials in this class are any materials containing radionuclides where both the activity concentration and the total activity in the consignment exceed the values specified in 2.7.7.2.1 to 2.7.7.2.6 of the IMDG Code.

Class 8: Corrosive substances: The materials in this class are materials which, by chemical action, will cause severe damage when in contact with living tissue or will materially damage, or even destroy, other goods or the means of transport.

Class 9: Miscellaneous dangerous substances and articles: The materials in this class are materials and articles which, during transport, present a danger not covered by other classes.

Some definitions:

Solid bulk cargo
means any cargo, other than liquid or gas, consisting of a combination of particles, granules or any larger pieces of material generally uniform in composition, which is loaded directly into the cargo spaces of a ship without any intermediate form of containment.

Dangerous goods in solid form in bulk means any material, other than liquid or gas, consisting of a combination of particles, granules or any larger pieces of material, generally uniform in composition, which is covered by the IMDG Code and is loaded directly into the cargo spaces of a ship without any intermediate form of containment, and includes such materials loaded in a barge on a barge-carrying ship.

Transportable Moisture Limit (TML) of a cargo which may liquefy means the maximum moisture content of the cargo which is considered safe for carriage in ships other than specially constructed or fitted cargo ships (see 7.3.2 of IMBSC Code for full details).

Let’s have a look at the provisions of carriage of dangerous goods in solid form in bulk.

IMDG Code deals with dangerous goods in packaged form. Packaged form means dangerous goods packed in packages specified in IMDG Code, eg; UN 1942 AMMONIUM NITRATE packed in Woven plastics water-resistant bags. If we load UN 1942 AMMONIUM NITRATE directly in to the holds of a cargo ship without packing in bags then the provisions of IMBSC Code has to be applied.

Cargoes are identified and listed in IMSBC Code with Bulk Cargo Shipping Name (BCSN). All names are listed in appendix 4 of IMSBC Code in an alphabetical order together with their group name and references if any.

In order to understand the provisions of carriage of dangerous goods in bulk let us look at FERROSILICON. In appendix 4 (Index of solid bulk cargoes) Ferrosilicon is listed as below

In Appendix 1 (Individual schedules of solid bulk cargoes) Ferrosilicon is listed and twice first entry reads FERROSILICON UN 1408 which is same as above listed in the index.

The entry in appendix 1 gives full details of Ferrosilicon UN 1408 as below

FERROSILICON UN 1408 with 30% or more but less than 90% silicon (including briquettes)

DESCRIPTION

Ferrosilicon is an extremely heavy cargo.

CHARACTERISTICS

ANGLE OF REPOSE	BULK DENSITY (kg/m3)		STOWAGE FACTOR (m3/t)
Not applicable	1389 to 2083 (1111 to 1538 for briquettes)		0.48 to 0.72 (0.65 to 0.90 for briquettes)
SIZE	CLASS		GROUP
Up to 300 mm Briquettes	4.3	6.1	B

HAZARD

STOWAGE & SEGREGATION

“Separated from” foodstuffs and all class 8 liquids.

HOLD CLEANLINESS

Clean and dry as relevant to the hazards of the cargo.

WEATHER PRECAUTIONS

This cargo shall be kept as dry as practicable before loading, during loading and during voyage. This cargo shall not be loaded during precipitation. During loading of this cargo all non-working hatches of the cargo spaces to which this cargo are loaded or to be loaded shall be closed.

LOADING

Trim in accordance with the relevant provisions required under sections 4 and 5 of the Code. As the density of the cargo is extremely high, the tanktop may be overstressed unless the cargo is evenly spread across the tanktop to equalize the weight distribution. Due consideration shall be paid to ensure that tanktop is not overstressed during voyage and during loading by a pile of the cargo. Refer to the appendix to this schedule.

PRECAUTIONS

The manufacturer or the shipper shall provide the master with a certificate stating that, after manufacture, the cargo was stored under cover, but exposed to dry weather for not less than three days prior to shipment.

VENTILATION

Continuous mechanical ventilation shall be conducted during the voyage for the cargo spaces carrying this cargo. If maintaining ventilation endangers the ship or the cargo, it may be interrupted unless there is a risk of explosion or other danger due to interruption of the ventilation. In any case mechanical ventilation shall be maintained for a reasonable period prior to discharge. Refer to the appendix to this schedule.

CARRIAGE

For quantitative measurements of hydrogen, phosphine and arsine, suitable detectors for each gas or combination of gases shall be on board while this cargo is carried. The detectors shall be of certified safe type for use in explosive atmosphere. The concentrations of these gases in the cargo spaces carrying this cargo shall be measured regularly, during voyage, and the results of the measurements shall be recorded and kept on board.

DISCHARGE

Refer to the appendix to this schedule.

CLEAN-UP

After discharge of this cargo, the cargo spaces shall be swept clean twice. Water shall not be used for cleaning of the cargo space which has contained this cargo, because of danger of gas.

EMERGENCY PROCEDURES

SPECIAL EMERGENCY EQUIPMENT TO BE CARRIED

Self-contained breathing apparatus.

EMERGENCY PROCEDURES

Wear self-contained breathing apparatus.

EMERGENCY ACTION IN THE EVENT OF FIRE

Batten down and use CO2 if available. Do not use water.

MEDICAL FIRST AID

Refer to the Medical First Aid Guide (MFAG), as amended.

The entry further contains APPENDIX: GENERAL REQUIREMENTS FOR CARRIAGE OF FERROSILICON and detailed requirements, operational requirements, gas releases from ferrosilicon impurities when water is added.

Under Precautions, see above, manufacturer or shipper is required to provide a certificate which is similar to IMDG Code requirement of ‘weathering certificate”.

Similar to Dangerous Goods transport document required by IMDG Code IMSBC Code require a declaration from shipper, see below image. This declaration must be furnished well in advance of loading to enable the precautions which may be necessary for proper stowage and safe carriage of the cargo to be put into effect.

Apart from Dangerous Goods listed in IMDG Code there are some goods which possess dangerous properties when carried in bulk. These goods are called Materials hazardous only in bulk (MHB).

One example of MHB is WOOD PELLETS. This is a group B cargo (cargoes which possess a chemical hazard), in appendix 1 class for this entry reads “MHB” with stowage and segregation requirement as for class 4.1 materials ( flammable solids)

Please refer to IMSBC Code for full details.

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