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

HAZARD

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.

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

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.