IMSBC Code
International Maritime Solid Bulk Cargoes Code — mandatory requirements for loading, trimming, carriage and discharge of solid bulk cargoes, including liquefaction risk assessment.
Adopted
2008
Mandatory
1 Jan 2011
Legal Basis
SOLAS Ch.VI
Applies To
Bulk Carriers
Cargo Groups
May Liquefy
Cargoes that may liquefy if shipped at moisture content in excess of their Transportable Moisture Limit (TML). Examples: Iron ore fines, nickel ore, coal, mineral concentrates.
Examples: Iron ore fines, nickel ore, bauxite fines, mineral concentrates
Chemical Hazard
Cargoes that possess a chemical hazard which could give rise to a dangerous situation on a ship. Examples: coal (methane/self-heating), sulfur (combustion), ammonium nitrate.
Examples: Coal, sulfur, ammonium nitrate, calcium carbide
Neither A nor B
Cargoes that are neither liable to liquefy nor possess chemical hazards, but may still present a physical hazard (shift of cargo, dust). Most grain shipments fall here.
Examples: Grain, fertilizer, salt, clinker, gravel, wood chips
Both Hazards
Cargoes that possess properties of both Group A and Group B. These require maximum precautions regarding both liquefaction risk and chemical hazards.
Examples: Some coal fines with both chemical hazard and liquefaction risk
Key Requirements
Moisture Content Testing
Shipper must declare moisture content. Independent testing required if moisture > 85% of TML. Tests: Penetration test, Can test, or Flow table test.
Transportable Moisture Limit (TML)
Maximum moisture content for safe carriage without liquefaction risk. TML = 90% of Flow Moisture Point (FMP). Must be certified by competent authority.
Cargo Declaration
Shipper must provide written declaration including: cargo name, IMSBC group, gross mass, stowage factor, moisture content, TML (Group A), and special properties.
Trimming
Bulk cargoes must be trimmed to avoid cargo shift. Especially important for Group A and C cargoes. Method and extent specified in individual schedule.
Weather Precautions
Many cargoes restrict loading in rain. Nickel ore: loading prohibited if moisture near TML. Coal: no loading if heavy rain expected.
Hold Preparation
Cargo holds must be clean, dry and structurally sound. Bilge suctions must be clear. Previous cargo residues must not contaminate new cargo.
Liquefaction Risk
Liquefaction is the phenomenon where saturated granular material behaves like a liquid. This has caused numerous bulk carrier losses with all hands.
High-risk cargoes
Iron ore fines, nickel ore
TML testing
Required before each voyage
Key test methods
Penetration, Can, Flow table
TML =
90% of Flow Moisture Point