Coal: IMSBC Code Schedule and Carriage

Coal is the single most-traded solid bulk cargo by sea. The IMSBC Code classifies it under a single schedule entry, COAL, with a dual Group A and B status: Group B because all coals self-heat, emit flammable methane, generate toxic carbon monoxide, and deplete oxygen in enclosed holds; Group A additionally for fine wet coals whose moisture content exceeds their transportable moisture limit and which can liquefy under the cyclic loading of a ship in a seaway. The global seaborne coal trade ran to approximately 1.3 to 1.4 billion tonnes in 2023, split between thermal coal for power generation and metallurgical coal for steel production.

The IMSBC Code, which became mandatory under SOLAS Chapter VI from 1 January 2011 through Resolution MSC.268(85), places coal in its Appendix 1 under the Bulk Cargo Shipping Name (BCSN) COAL. That single schedule entry covers every coal type from lignite through sub-bituminous and bituminous to anthracite. The hazard profile changes materially with coal rank, fines content, and moisture, so the schedule must be read with the shipper’s cargo declaration for each individual consignment. Coal is responsible for a large share of the total recorded bulk-carrier fire casualties, and the IMSBC Code’s requirements for coal represent some of the most detailed and operationally demanding carriage rules in the Code.

The Coal Self-Heating Indicator calculator and the Coal Methane Ventilation Rate calculator on this site support the operational calculations that the COAL schedule requires. Separate schedule entries for COAL (ANTHRACITE), COAL (BITUMINOUS), and COAL (LIGNITE) cover those grade-specific handling parameters.

The global coal trade and cargo grades

Coal seaborne trade has two distinct commodity streams with different hazard profiles. Thermal coal (also called steam coal or power station coal), which accounts for approximately 70 percent of seaborne trade by volume, is burned in power stations and industrial boilers. The major thermal coal export origins are Indonesia (around 440 to 490 million tonnes per year), Australia (around 200 million tonnes per year), Russia (around 150 to 170 million tonnes per year), the United States, and South Africa. The main import destinations are China, India, Japan, South Korea, and European utilities.

Metallurgical coal (also called coking coal or met coal) is used in blast-furnace steelmaking and accounts for roughly 300 to 320 million tonnes per year of seaborne trade. Australia is the dominant exporter, supplying around 55 to 60 percent of the seaborne coking coal market, with the United States and Canada as secondary sources. Japan, China, South Korea, and India are the principal importers.

Coal rank matters for hazard purposes. Lignite (brown coal) is the lowest rank and is wet, low-energy, and prone to both spontaneous combustion and self-heating. Sub-bituminous coal sits in the middle range. Bituminous coals, the most widely traded grade, include both high-volatile types that are significant methane emitters and lower-volatile types used in metallurgy. Anthracite is the highest-rank coal, hardest, densest, and least prone to both methane emission and spontaneous combustion, though not entirely free of either hazard. The IMSBC Code’s single COAL schedule covers all these grades; the companion grade-specific schedule entries (LIGNITE, BITUMINOUS COAL, ANTHRACITE) provide additional handling notes for specific grades.

Bulk carriers that carry coal range from small handysize vessels of 25,000 to 40,000 dwt on short-sea trades to Capesize vessels of 150,000 to 210,000 dwt on long Pacific routes. Voyage durations range from 2 to 3 days on regional trades to 15 to 20 days on the Australia-to-Japan or Colombia-to-Europe routes. The longer the voyage, the greater the cumulative gas and heat build-up in sealed holds.

IMSBC Code dual Group A and B classification

The COAL schedule assigns coal simultaneously to Group A and Group B, the only widely-traded bulk cargo besides certain sulphide and zinc-lead concentrates to carry this dual classification. Group B applies to all coals because of the chemical hazards of self-heating, methane emission, carbon monoxide generation, and oxygen depletion. Group A applies additionally to fine coals that have a significant fraction of particles below 1 mm and a moisture content above their transportable moisture limit, which creates a liquefaction or dynamic separation risk.

The IMSBC Group B classification covers the chemical hazards. Every consignment of coal, regardless of grade, rank, or origin, is Group B. The shipper is required to declare whether the coal is additionally Group A, based on the fines content and moisture characterization. If the coal is Group A and B, pre-loading TML testing and moisture content certification are required in addition to all the Group B monitoring requirements.

The IMSBC Group A classification for coal relates to the phenomenon formally called dynamic separation (introduced into the Code by Amendment 06-21, Resolution MSC.500(105), mandatory from 1 December 2023). Fine coal particles and water can migrate to the surface of the cargo under ship motion, forming a slurry on top of the still-solid bulk, producing a free-surface effect analogous to full liquefaction. The 06-21 amendment revised the Group A definition to explicitly cover this mechanism.

COAL schedule: key particulars

Self-heating: the primary chemical hazard

All coals undergo exothermic low-temperature oxidation when exposed to air. In a sealed cargo hold the heat released by this reaction cannot dissipate, temperatures rise progressively through the voyage, and if not controlled the cargo can spontaneously ignite. The progression runs from slow surface oxidation at ambient temperatures through accelerated reaction above about 40 to 60 degrees Celsius to active combustion above roughly 100 to 150 degrees Celsius, generating carbon monoxide in proportion to the oxidation rate.

The mechanism is oxidation of carbon and sulfur compounds in the coal matrix. Fresh coal surfaces, exposed by crushing and handling during loading, are the most reactive zones. The reaction rate doubles roughly every 10 degrees Celsius of temperature increase (a rule of thumb from the Arrhenius relationship), so the early warning period available to the master depends heavily on the initial cargo temperature at loading. A coal loaded at 25 degrees Celsius that begins to self-heat has a longer runway before reaching dangerous temperatures than one loaded at 40 degrees Celsius.

Certain coal types are more prone to self-heating. High-volatile bituminous coals and sub-bituminous coals are the most reactive; anthracite is the least. Fines fractions heat faster than lumps because they present more surface area per tonne. Wet coals can inhibit surface oxidation in the short term but can release heat rapidly as they dry within the hold over the voyage. Coals that have been stored at the loading terminal for extended periods before loading may have partially oxidized and weathered, making them less reactive, but pre-weathered coals can still self-heat if fresh interior surfaces are exposed by stockpile handling.

The IMSBC Code requires the shipper to declare whether the coal is self-heating. In practice, all coals must be treated as potentially self-heating unless the cargo declaration specifically attests otherwise based on documented testing. Carbon monoxide monitoring is the principal shipboard tool for detecting active self-heating before temperatures rise to dangerous levels. CO forms as an intermediate product of coal oxidation; it appears in the hold atmosphere before any measurable temperature rise is detectable in the cargo body, making it a reliable early warning indicator.

The Coal Self-Heating Indicator calculator on this site computes the self-heating risk index from the coal’s reported proximate analysis values.

Temperature thresholds and monitoring

The IMSBC Code does not set a single universal action temperature for coal, but industry practice and the P&I club guidance documents treat the following thresholds as operational benchmarks:

• Up to 40 degrees Celsius: normal cargo temperature range at departure for most origins.
• 40 to 55 degrees Celsius: the initial warning zone; increase monitoring frequency.
• 55 degrees Celsius: the critical threshold for loading petcoke cargoes and the informal action threshold for coal in many flag-state guidance documents.
• Above 65 to 70 degrees Celsius: active oxidation confirmed; implement emergency procedures.

Temperature is measured at hold sampling points or via installed temperature probes where fitted. Many older bulk carriers do not have hold temperature sensors, relying entirely on CO monitoring. Newer bulk carriers on dedicated coal trades increasingly fit temperature probe arrays at multiple hold depths, giving a better picture of the cargo cross-section temperature gradient.

Methane emission: the explosive atmosphere hazard

Higher-rank coals, particularly coking coals, bituminous coals, and sub-bituminous coals, contain methane (CH4) adsorbed in the coal matrix under geological pressure. When the coal is mined, crushed, and loaded into a bulk carrier hold, the methane desorbs progressively and accumulates in the hold headspace. Methane is flammable between 5 and 15 percent in air (the lower and upper explosive limits respectively); concentrations within that range with an ignition source will explode, and concentrations below 5 percent can still ignite with enough energy.

The rate of methane emission is highest in the first 24 to 72 hours after loading, as the fresh surfaces exposed by handling desorb the most gas. Emission continues throughout the voyage at a declining rate. The Code’s ventilation requirements for methane-emitting coals are designed to prevent accumulation in the hold headspace above safe concentrations during this high-emission phase.

Methane emission is not limited to the hold atmosphere. The gas can migrate through hatch covers if they are not in good condition, accumulating in under-deck spaces, crew spaces located above or adjacent to holds, and in the hatch cover cofferdam areas. Several casualties and near-misses have involved methane migrating into spaces where ignition sources were present, rather than igniting in the hold itself.

The IMSBC Code schedule for COAL requires the shipper to declare whether the coal is methane-emitting. Methane emitting status correlates with coal rank: generally, bituminous and coking coals above about 80 percent carbon content on a dry ash-free basis are classified as methane-emitting; sub-bituminous and lignite coals are not typically methane-emitting in the IMSBC sense, though they present different self-heating profiles.

Carbon monoxide generation and oxygen depletion

Coal self-heating generates carbon monoxide (CO) as an intermediate combustion product of the oxidation reaction. CO is toxic at concentrations above 50 parts per million in air for extended exposure (the short-term occupational exposure limit in many jurisdictions is 200 to 400 ppm for 15 minutes). In a sealed coal hold with active self-heating, CO concentrations can rise to hundreds or thousands of ppm, turning the hold atmosphere immediately dangerous to anyone who opens a hatch or enters without breathing apparatus.

CO accumulation is also a direct indicator of the rate of self-heating. An upward trend in CO readings from a sealed hold, even if absolute concentrations are not yet at dangerous levels, tells the master that oxidation is accelerating. A doubling of CO concentration over 24 hours is a recognized action trigger in P&I club guidance, warranting notification of the shipper and preparation of emergency response procedures.

Oxygen depletion is a parallel hazard. The oxidation reaction in a sealed coal hold consumes oxygen from the hold atmosphere. In holds that are not ventilated, the oxygen content can fall below 19.5 percent, which the IMSBC Code and SOLAS recognize as the threshold below which a confined space is unsafe for entry without supplied air breathing apparatus. Holds can reach oxygen levels of 16 to 17 percent with active self-heating over a multi-week voyage.

The combined hazard picture means that a coal hold after a long voyage can simultaneously contain: an elevated CO concentration (toxic), a flammable methane atmosphere (explosive), and a depleted oxygen level (asphyxiating), making any unprotected entry immediately life-threatening. This combination has killed crew members who opened hatches to inspect cargo or who entered holds without atmospheric testing. SOLAS requirements for confined space entry, and IMO guidance on enclosed space entry, must be applied before any entry into a coal hold, regardless of the length of the voyage.

Acid formation and corrosion

A hazard less widely discussed than fire or gas, but documented in the IMSBC Code, is the corrosive effect of coal cargo on steel structures. Coals with a significant sulfur content can form sulfuric and sulfurous acids in the presence of moisture and oxygen. These acids attack the hold structure, frame brackets, frames, and stiffeners. Coals that have been washed in sea water or that contain high moisture can accelerate this process.

Bilge water from coal holds is acidic and corrosive. Bilge systems in coal-carrying vessels require inspection after each coal voyage, and hold-coating damage from acid attack is a documented inspection finding for class society surveyors. The acidic bilge water also creates a disposal challenge; it cannot be discharged overboard without treatment under MARPOL Annex I requirements, and port reception facilities must be used.

Corrosion from coal cargoes has been a contributor to structural wastage in older bulk carriers and is one of the reasons that dedicated coal carriers typically specify hold coatings rated for acid service, rather than the standard epoxy coatings used for general dry bulk service.

Liquefaction in fine coal: the Group A hazard

Fine coal, particularly coal with a high fines fraction below 1 mm in particle size and moisture content at or above its transportable moisture limit, can liquefy or dynamically separate in a bulk carrier hold. The IMSBC Code classifies fine coals meeting the Group A criteria as Group A and B, requiring pre-loading TML and moisture content testing using the same methods applied to iron ore fines, nickel ore, and other Group A mineral cargoes.

The cargo liquefaction mechanism in coal is the same as in other Group A cargoes: ship motion repeatedly shears the fine moist cargo, pore-water pressure builds faster than the water can drain, effective stress falls, and the cargo loses shear strength and flows. The resulting free liquid surface within the hold shifts with each roll, producing a correcting moment that grows until the ship cannot self-right and capsizes.

Fine coal origins that have historically presented elevated liquefaction risk include:

• Indonesian steam coal, particularly from Kalimantan mines, which can have high moisture and fine particles from the mining and washing process.
• Chinese coastal coal, particularly coal from inland mines transported by river barge and loaded at coastal transshipment terminals.
• US Gulf thermal coal, some grades of which contain elevated fines from rail transport.
• South African and Colombian coals where washing plant failures have allowed moisture content to exceed TML.

Dynamic separation, the mechanism formally added to the Code by Amendment 06-21, is distinct from bulk liquefaction. In dynamic separation the fine particles and water migrate toward the top of the cargo under the vibration and motion of the ship, forming a water-and-fines slurry over a still-stable bulk layer. This slurry has the same free-surface effect as a liquefied cargo and has been associated with several bauxite casualties and, in coal, with incidents where the hold floor was stable but the cargo top surface was fluid.

Pre-loading, the TML test report and a moisture content certificate showing moisture below TML must both be presented to the master before loading a Group A and B coal. The cargo liquefaction article covers the TML test methods in detail.

Ventilation: the methane-versus-self-heating conflict

The central operational conflict in coal carriage is that the two principal hazards, methane emission and self-heating, require opposite ventilation strategies. Methane control requires ventilating the hold headspace to dilute and flush the gas. Self-heating control requires minimizing oxygen supply to the cargo body, which means minimizing or stopping ventilation. The IMSBC Code resolves this through surface ventilation: a regime that circulates air across the cargo surface and headspace without driving fresh oxygen into the cargo body.

Surface ventilation works through the hold ventilation system by maintaining a positive pressure at the headspace from external air and allowing headspace air to exit through other ventilation outlets, without creating any through-current that passes into and through the cargo mass. This is operationally different from through-ventilation, which creates a current that penetrates the cargo pile, oxygenates the interior, and directly feeds the self-heating reaction.

The practical application of the Code requirement is as follows:

When the CO reading in a sealed hold begins to rise, confirming self-heating, the response is to seal the hold and cut all ventilation, starving the reaction of oxygen. This takes priority over methane ventilation because a coal fire is harder to extinguish than a methane build-up is to manage.

When methane is the primary concern, surface ventilation is maintained or increased to dilute the headspace concentration below the lower explosive limit. The ventilation system fans are run but the air distribution is limited to the headspace through the design of the ventilation duct arrangement.

When both hazards are present simultaneously, which is common early in a voyage when methane emission is high and the cargo is beginning its thermal response, the master must make a judgment call with the shipper, the P&I club, and the flag state guidance. The general priority in current practice is: if CO is rising, seal and do not ventilate; if methane is rising and CO is stable, surface ventilate.

The Coal Methane Ventilation Rate calculator computes the ventilation rate required to maintain headspace methane below action thresholds.

No smoking and no naked lights

The IMSBC Code schedule for COAL requires no smoking, no naked lights, and no hot work in the vicinity of cargo holds throughout the voyage. This requirement is binding from the moment the cargo is on board and is not suspended until all hatches are open and the holds have been confirmed gas-free at discharge. The risk is not limited to hold explosions: methane that has migrated through imperfect hatch covers into adjacent spaces or under-deck cofferdam areas has ignited from galley exhausts, engine casing vents, and electrical equipment in accommodation areas located above cargo holds.

Cargo declaration: the shipper’s obligations

The IMSBC Code places the obligation to characterize and declare the coal cargo squarely on the shipper. The cargo declaration for a coal consignment must include:

1. The cargo name and Bulk Cargo Shipping Name (BCSN): COAL, or the grade-specific name.
2. The group classification: Group B, or Group A and B.
3. If Group A and B: the TML test report and the moisture content certificate, both dated within the three-month testing window before loading.
4. Whether the coal is self-heating and the degree of self-heating tendency, based on the shipper’s knowledge of the coal type and origin.
5. Whether the coal is methane-emitting, based on the rank and provenance.
6. The stowage factor.
7. The angle of repose.
8. Any special conditions or handling notes that the shipper considers necessary based on the coal’s characteristics.

The master is entitled to refuse to load if the cargo declaration is incomplete or if the declared moisture content exceeds the TML for a Group A and B coal. Charterparty clauses frequently create commercial pressure on masters to accept incomplete declarations; the IMSBC Code’s requirements are mandatory under SOLAS and cannot be overridden by private contract.

Shippers from some origins have historically under-declared fines content or moisture content to avoid the additional testing burden. Class societies, P&I clubs, and port-state control regimes have tightened sampling and testing requirements in response, and independent pre-loading surveys are now standard practice for many operators on high-risk origins.

Hold preparation before loading coal

The IMSBC Code requires holds to be clean and dry before loading coal. Specific requirements include:

• All cargo residues from previous voyages removed.
• Bilge wells and bilge piping clean and functional, with bilge pump tested.
• Hold coating in acceptable condition; the Code does not specify a coating standard but class society guidance recommends no open corrosion pits or coating delamination that could trap coal fines.
• Hold ventilation system, including ducts, fans, and closures, in working order and tested.
• Hatch covers in good condition, seals intact, drain channels clear, and all hatch cover bolts fastened. Methane leakage through imperfect hatch covers is a documented ignition pathway.
• Temperature monitoring equipment (where fitted) calibrated and operational.
• Gas detection equipment calibrated and ready, with spare tubes or sensor cells for CO, methane, and O2 detection.

For coal loaded after a sensitive cargo such as grain or after a hold washing with strong detergents, the hold must be thoroughly dried before coal loading. Water ingress into a coal hold from a previous washing raises the risk of coal-water acid formation and can raise the effective moisture content in the lower hold.

Gas monitoring procedures during the voyage

The IMSBC Code requires monitoring of the cargo hold atmosphere throughout the voyage. The industry standard for coal monitoring, as elaborated in P&I club guidance and class-society cargo-practice notes, is:

• CO monitoring: daily from each hold using either portable CO detector tubes drawn through the hold sampling lines (typically stainless steel tubes penetrating the hatch cover), or continuous electrochemical sensors where fitted.
• Methane monitoring: daily, using the same sampling lines, with a calibrated catalytic combustion or infrared methane detector.
• Oxygen monitoring: whenever the hold may be entered, using a calibrated electrochemical oxygen sensor; and at intervals during the voyage to track depletion trends.
• Cargo temperature: where probe arrays are fitted, continuous logging; otherwise intermittent readings at sampling points.

Readings are logged in the cargo record book. When CO readings show an upward trend over consecutive days, the master should notify the shipper and the company, increase monitoring frequency to every six hours, prepare CO2 or inert gas injection for hold flooding, and consider diverting to the nearest port of refuge if the trend continues.

A CO concentration above 200 ppm in a sealed hold is an internationally recognized emergency threshold requiring immediate action. Concentrations above 50 ppm in sealed holds, or any sudden increase, warrant increased monitoring and notification.

Hold firefighting for coal

A smouldering coal fire in a bulk carrier hold is one of the most difficult firefighting situations in the merchant fleet. Direct water application is inappropriate for a cargo fire in a sealed hold because the steam generated by water contact can scatter hot burning material, and the added water increases the weight in the hold with little benefit to fire suppression. The IMSBC Code prescribes the following emergency approach:

1. Close all hatches, ventilation openings, and access points to the affected hold immediately. Oxygen starvation is the primary control method.
2. Flood the hold with CO2 from the ship’s fixed CO2 system (if fitted with coverage for cargo holds), or with inert gas from shore or a portable inert gas generator.
3. Do not re-open hatches until the CO level has fallen and the temperature has stabilised; opening a hatch to a hot smouldering hold causes flashover as oxygen is suddenly introduced.
4. Divert to the nearest suitable port of refuge. Notify the port authority, harbour master, emergency services, the flag state, and the P&I club.
5. On arrival, with emergency services attending, discharge the cargo in a controlled manner into a flat area ashore. Emergency services can then apply water to the discharged burning coal.

The marine fire detection and fixed fire fighting systems article covers the shipboard fire suppression systems relevant to cargo hold fires. Not all bulk carriers have fixed CO2 systems covering cargo holds; their absence sharply limits the emergency options available to the master.

Water mist systems and CO2 injection have both been used successfully to control coal fires in bulk carrier holds. The critical point in the IMSBC guidance is that no water should reach the cargo body mass while the cargo remains in the hold, and hatches must not be opened once a fire is confirmed.

Documented casualties and incidents

Coal cargo casualties have caused a significant number of bulk carrier losses and crew deaths in the past four decades. The following are documented incidents drawn from official investigation reports and IMO correspondence:

MV Parita (1994): The vessel suffered a coal hold fire during a voyage from Colombia to Europe. Investigation established that CO levels had been rising for several days before the fire became open combustion. The ventilation regime applied was through-ventilation rather than surface ventilation, which fed the self-heating reaction. The incident prompted international guidance on coal ventilation practice.

MV Asian Forest (2003): The Panamanian-flagged bulk carrier suffered a cargo fire in a hold loaded with Indonesian steam coal. The fire developed after a multi-week voyage with inadequate CO monitoring. The investigation cited failure to act on early CO readings as the primary contributing cause.

MV Wilhelmine (and several unnamed vessels from Indonesia trades, 2011 to 2015): The Indonesian coal trade produced multiple documented events involving cargo declarations that under-stated fines content and moisture content, leading to unexpected liquefaction events. The period from 2011 to 2015 saw the Indonesian cargo classification issue escalate to the level of IMO CCC Sub-Committee submissions and formal correspondence from the Indonesian flag administration and the Indonesian Coal Mining Association.

MV Bulk Jupiter (2015): While primarily a Group A bauxite liquefaction casualty, this casualty accelerated the formal revision of the Group A definition to cover dynamic separation, which had direct relevance to the coal trade because of fine coal’s susceptibility to the same mechanism. The 2015 CCC Sub-Committee session following the Bulk Jupiter loss led directly to the work programme that produced Amendment 06-21.

Multiple vessel hold-entry fatalities: A recurring pattern in bulk carrier incident records involves crew members entering coal holds without atmospheric testing, dying from CO poisoning or oxygen depletion, and in some instances being followed by a second fatality when a colleague attempts a rescue without breathing apparatus. These incidents have occurred at ports of discharge when hatches are first opened, during voyage inspections, and during hold gas measurement attempts without correct equipment.

The pattern across the casualty record is consistent: the incidents that cause the worst outcomes involve late detection of CO rise, incorrect ventilation practice (through-ventilation when self-heating is the concern), inadequate hold-entry controls, and cargo declarations that did not accurately characterize the coal’s hazard properties.

Shipper responsibilities and the coal declaration supply chain

The IMSBC Code’s framework for coal relies on a supply chain of information from the coal mine, through the exporter and shipper, to the ship. In practice this chain has several documented weak links.

Coal exported from some origins passes through multiple handlers between the mine and the ship: the mine operator, a domestic road or rail haulier, a domestic terminal or blending facility, a coastal transhipment terminal, and finally the vessel. Each transfer introduces the possibility of contamination with wetter coal from a different source or loss of the original test data. The IMSBC Code requires the declaration to reflect the actual cargo loaded, not the original mine sample, but verification that the declaration matches the loaded cargo depends on independent sampling at the vessel loading point.

Pre-loading moisture sampling and testing by an independent surveyor, typically a Lloyds Agency or a P&I correspondent surveyor, is standard practice for quality-aware operators on the Indonesian, Chinese, and South African trades. Some charterparties include an explicit clause requiring cargo-side sampling before the master issues a mate’s receipt. Where no such clause exists, operators relying solely on the shipper’s declaration carry the full risk of an inaccurate Group A and B assessment.

Comparisons with related Group B cargoes

Coal shares its Group B self-heating and gas-emission hazard profile with two other major bulk cargoes: petroleum coke and brown coal briquettes.

Petroleum coke (petcoke) is more reactive in self-heating than most bituminous coals, with a stricter 55-degree Celsius loading temperature criterion, but does not emit methane and is not Group A. The ventilation dilemma is therefore absent: surface ventilation is consistently the right answer for petcoke, without the methane-versus-self-heating trade-off that makes coal harder to manage.

Brown coal briquettes are compressed lignite and share the self-heating profile of coal without the methane emission of higher-rank coals. They are Group B only. The briquetting process creates a denser, more compact product that tends to limit surface oxidation compared to run-of-mine coal fines.

Direct reduced iron (DRI) and hot briquetted iron (HBI) are Group B cargoes with a water-reactive hazard rather than a self-heating-and-gas profile: they react with moisture to generate hydrogen and can also self-heat. DRI is more hazardous in this respect than coal because the reaction is faster and the hydrogen evolution is directly proportional to moisture contact.

Limitations

This article describes the IMSBC Code COAL schedule as it stands under the current mandatory edition incorporating Amendments 06-21 (MSC.500(105), mandatory from 1 December 2023) and 07-23 (MSC.539(107), mandatory from 1 January 2025). Subsequent amendments may modify the schedule, the group classification tests, or the ventilation requirements; the master and operator must always verify that the edition of the IMSBC Code on board is the current mandatory edition.

The hazard parameters given in this article are those stated in the Code and in recognized industry guidance. Actual hazard levels for any specific coal shipment depend on the coal’s proximate and ultimate analysis, its rank, its fines fraction, its moisture content history, and the conditions of storage, loading, and the voyage. The IMSBC Code requires that each consignment be assessed individually on the basis of the shipper’s declaration and any independent testing obtained by the operator.

This article does not substitute for the IMSBC Code text itself, for flag-state or class-society guidance specific to the operator’s vessels and flag, or for the advice of the P&I club and a qualified marine surveyor familiar with the coal trade. Gas and temperature data observed during a voyage must be assessed by a qualified marine professional, not by reference to an encyclopedia article alone.

The monitoring thresholds cited in this article (50 ppm CO action, 200 ppm CO emergency, 20 percent of LEL for methane, 19.5 percent O2 for safe entry) are derived from IMSBC Code text, SOLAS requirements, and recognized P&I club guidance documents. Some flag-state administrations may specify different thresholds; the flag-state requirements govern.

See also

• IMSBC Code
• IMSBC Group A cargoes: Cargoes that may liquefy
• IMSBC Group B cargoes: Cargoes with chemical hazards
• Cargo liquefaction
• Petroleum Coke: IMSBC Code Schedule
• Brown Coal Briquettes: IMSBC Code Schedule
• Marine fire detection and fixed fire fighting systems

Related calculators:

• Coal Self-Heating Indicator
• Coal Methane Ventilation Rate
• IMSBC Coal (Lignite)
• IMSBC Coal (Bituminous)
• IMSBC Coal (Anthracite)
• Cargo Heat: Spontaneous Combustion
• IMSBC Group A/B/C Classification