What is the IMSBC Code?

IMSBC Code, the International Maritime Solid Bulk Cargoes Code

The carriage of solid bulk cargoes on board bulk carriers involves a number of risks that must be properly managed to ensure the safety of the vessel and its crew on the high seas. These risks include poor vessel stability, capsizing due to liquefaction of the cargo, explosions or fires caused by hazardous chemicals, and structural damage to the vessel due to improper loading operations.

The IMSBC Code, the International Maritime Solid Bulk Cargoes Code, is a regulation for the safe carriage of solid bulk cargoes that became mandatory on 1 January 2011 under the International Convention for the Safety of Life at Sea (SOLAS). The Code is contained in its Chapters VI and VII. The IMSBC Code also applies to seagoing vessels of less than 500 gross tonnage.

Importance of the International Solid Bulk Cargoes Code (IMSBC Code)

The International Solid Bulk Cargoes Code (IMSBC Code) replaces the Code of Safe Practice for the Carriage of Solid Bulk Cargoes (BC Code). The Code aims to ensure the safe transport of solid bulk cargoes, providing details and instructions on the correct procedures to be followed when loading, trimming, handling and unloading solid bulk cargoes during transport. The Code also identifies the hazards that may exist when transporting certain types of solid bulk cargoes.

The International Solid Bulk Cargoes Code (IMSBC Code) does not cover the transport of bulk grain as specified in the International Code for the Safe Transport of Grain in Bulk (ICBG, 1991).

The International Solid Bulk Cargoes Code is revised every two years. The 2015 and 2017 revisions added additional safeguards for cargoes that may liquefy and whose transportable moisture limit (TML) must not be exceeded.

The IMSBC Code was updated in June 2023, with revision 07-23 taking effect on January 1, 2025. The revision lists the new cargoes added to the Code.

Cargo categories in the IMSBC Code

The IMSBC Code divides cargoes into three categories.

Category A: includes cargoes that may liquefy (become liquid) when the moisture content exceeds the transportable moisture limit (TML) during transport. For example, water and oil can cause the cargo to shift.

Category B: This cargo may present chemical hazards that may cause dangerous conditions on board, such as self-heating, toxicity, oxygen evolution, and dust explosions.

This cargo is divided into:

Dangerous goods classified under the International Maritime Dangerous Goods Code (IMDG Code) that do not pose a hazard when transported in bulk.

Dangerous goods in bulk (MHB) include cargoes that may present chemical hazards when transported in bulk. These hazards include other hazards not listed in the International Maritime Dangerous Goods Code (IMDG Code).

Dangerous goods classified under the International Maritime Dangerous Goods Code (IMDG Code) may also present other MHB hazards.

Annex 1 of the International Maritime Solid Bulk Cargoes Code (IMSBC Code) details the characteristics, hazards, storage and segregation procedures, requirements, and preventive measures for each solid bulk cargo.

Group C: includes dangerous goods not classified as Group A or Group B.

Group A and Group B: This group includes cargoes that contain both Group A and Group B hazards.

Shippers must complete a cargo declaration form to identify the type of cargo being transported.

Cargo types covered by the IMSBC Code include coal, ores (e.g., bauxite), sulphur, direct reduced iron, fertilizers (e.g., sugar), wood pellets and ammonium nitrate.

Test Certificates

Under the IMSBC Code, test certificates are required for certain materials. The material must be tested and certified in a laboratory recognized in the Netherlands. The testing of the cargo depends on the cargo class to which it belongs. The conditions of transport also determine the testing requirements and timing.

Sometimes, a laboratory recognized in the Netherlands cannot meet the requirements of the IMSBC Code. In this case, the following provisions apply:

1. If the cargo is shipped directly from the country of origin to the country of destination, the test conducted in the country of destination will be recognized as valid. However, the competent authority of that country must recognize the laboratory, and proof of this recognition must be provided.

2. If the cargo stops in the Netherlands for reloading and then continues on its new journey, a test carried out in another EU Member State will be recognised. However, the competent authority of that country must recognise the laboratory, and proof of this recognition must be provided.

IMSBC Code Requirements for Group A Cargoes

Because Group A cargoes are susceptible to liquefaction and shifting, which could result in the vessel capsizing or even total loss, certain procedures must be followed to prevent such events.

To prevent liquefaction, Group A cargoes are tested before carriage to determine their safe maximum transportable moisture content (TML) and actual moisture content. The actual moisture content must be less than the Total Moisture Limit (TML).

The shipper must provide the master with certain information, including a signed certificate of maximum moisture content and a signed certificate or declaration of actual moisture content.

Follow these steps to reduce the risk of liquefaction:

Ensure that the shipper has provided all necessary information, including the maximum and actual moisture content.

Accept the cargo when the actual moisture content is less than the TML.

Visually monitor and inspect the cargo during loading. Stop loading if an increase in moisture content is observed.

Consider reducing the cargo’s size to minimize the risk of shifting. Take appropriate measures to prevent water or other liquids from entering the cargo area.

Examples of Group A cargoes include metal concentrates such as copper, iron, lead, nickel, and zinc.

IMSBC Code requirements for Class B cargoes

According to the IMSBC Code, Class B cargoes are divided into two categories: solid bulk dangerous goods (according to the IMSBC Code) and dangerous goods in bulk only (MHB).

According to the regulation, solid bulk dangerous goods are classified as follows:

Class 4.1: Flammable solids

Class 4.2: Pyrophoric solids

Class 4.3: Substances which, in contact with water, release flammable gases

Class 5.1: Oxidizing substances

Class 6.1: Toxic substances

Class 7: Radioactive substances

Class 8: Corrosive substances

Class 9: Other dangerous substances and materials

Class B cargoes

Includes:

• Flammable solids
• Pyrophoric solids
• Solids that, in contact with water, release flammable gases
• Solids that, in contact with water, release toxic gases
• Solids that are toxic to humans by inhalation or in contact with the skin
• Substances that are corrosive to the skin, eyes, and metals

Class B cargo examples Class B cargoes include coal, direct reduced iron, metal sulphide concentrates, organic matter, ammonium nitrate-based fertilizers, and wood products such as logs, pulpwood, sawn timber, and lumber.

To transport dangerous goods in bulk, your vessel must hold a Dangerous Goods Compliance Document. The flag state or classification society provides this document.

The master must also have a cargo manifest or stowage plan that indicates the location of the cargo, and emergency response instructions must be readily available on board.

Additionally, many Class B cargoes are incompatible and must be transported separately due to potential hazards.

Risk Mitigation Measures Associated with Class B Cargoes

The cargo manifest and information provided by the shipper indicate the precautions that should be taken when transporting Class B cargoes. The following are some common risk mitigation measures.

To prevent fires or explosions, the cargo hold and nearby enclosed spaces must be properly ventilated. The ventilation system must be explosion-proof, and the air in the cargo hold must be monitored using gas detectors.

The use of a ventilation system can reduce the risk of toxic gas leaks. The type of system used depends on the type of cargo and the characteristics of the gas.

Some cargoes can be corrosive, so a layer or barrier can be placed on the cargo hold structure before loading to ensure that the cargo hold is clean and dry.

Class C cargo requirements under the IMSBC Code

While Class C cargoes do not present the risks associated with Class A and B cargoes, they still pose a risk.

Examples of Class C cargoes include high-density cargoes, sand, fine particles (such as silica dust, which can cause respiratory problems when inhaled), and cement.

Some Class C cargoes can be very dense and can burden the cargo deck. It is therefore important to ensure that the cargo weight is evenly distributed during loading and navigation to avoid overloading the cargo deck. The symmetry of the cargo must also be taken into account.

Additionally, appropriate precautions must be taken to protect machinery and accommodation spaces from dust, sand, and fine particles, as well as to prevent cargo from entering the ballast tanks.

Crew members exposed to cargo dust must wear protective glasses and other protective equipment, such as masks and protective clothing.

If a solid bulk cargo is listed in Annex 1 to the IMSBC Code, the provisions of sections 1 to 10 and paragraph 11.1.1 of the IMSBC Code apply. The requirements of the relevant Annex also apply. This Annex describes the characteristics, hazards, and special requirements related to stowage, segregation, hold cleaning, climatic precautions, loading, ventilation, transportation, unloading, and emergency procedures.

If the solid bulk cargo is waste

Solid bulk cargoes may also be considered waste. If the shipment is carried across borders by ship, an EVOA or EWSR declaration must be submitted before sailing.

It is essential to note that the EVOA declaration is distinct from the approval for the transportation of solid bulk cargoes.

If the product is listed in Annex 1 of the International Maritime Bulk Cargoes Code (IMSBC Code), it can be transported as a solid bulk cargo. Otherwise, you need to sign an agreement with the exporting country.

Cargo Handling and Transportation Certificate

If the cargo to be transported is not listed in the International Maritime Bulk Cargoes Code (IMSBC Code) and is classified as Category A or B cargo, the cargo owner must sign a Tripartite Interim Agreement (TIA).

You can apply for an Approval for Transport (ATP) from the maritime authorities of the country where the cargo is to be shipped.

For Category C cargoes, an ATP is not required, but a notification from the competent authorities of the exporting country must be obtained. For this purpose, the cargo owner must also contact the maritime authorities of the country where the cargo is to be shipped.

The IMSBC Code is a set of guidelines issued by the International Maritime Organization (IMO) to ensure the safe transport of solid bulk cargoes. The Code establishes standards for the handling, storage, and transportation of solid bulk cargoes to mitigate the risks of cargo transshipment, liquefaction, and fire that threaten crew, ships, and the marine environment. The Code is a crucial component of international shipping regulations, and compliance with the Code ensures maritime safety on the high seas.