Stuffing Rules for Charcoal Containers: Temperature, Headspace, Stacking
By Mohamad Sinno, Charcoal Expert · Reviewed by Budi Hartanto, shipping specialist, 25 years in forwarding as of 2026 · Last updated
Charcoal ships as UN 1361, Class 4.2, so stuffing compliance is a carriage condition: packed at 40 °C or less on the packing day, after weathering of 14 days minimum or the steam-and-inert-gas route. SP 978.6 then requires 30 cm of headspace, grading the stow softer: under 1.5 m, or 16 m³ blocks 15 cm apart.
Charcoal packs at 40 °C or less, with 30 cm of headspace above the stow
SP 978, introduced by IMDG Amendment 42-24 and mandatory from 1 January 2026, sets the conditions a charcoal stuffing runs under: weathering before packing, a packing-day temperature ceiling and a minimum headspace, each a requirement, plus a stow-geometry limit graded softer. This is one layer of the container plan a charcoal FCL is loaded and costed against, which also settles tonnage by shape, the incoterm and the sea leg.
| Requirement | In the clause’s words | Clause | Source |
|---|---|---|---|
| Weathering | Shall weather under cover in the open air a minimum period of 14 days; or steam, cooling, inert gas, 24 h | SP 978.4 | CINS, Sept 2024 |
| Packing temperature | Shall be packed only when the temperature of the material does not exceed 40 °C on the day of packing | SP 978.5 | CINS, Sept 2024 |
| Headspace 30 cm | Minimum 30 cm in the CTU shall be maintained | SP 978.6 | CINS, Sept 2024 |
| Stack height limit | Stowage height should not exceed 1.5 m; or blocks should be 16 m³, 15 cm apart | SP 978.6 | CINS, Sept 2024 |
Hapag-Lloyd books against those three and wants the dates and readings on the declaration (December 2025); it says nothing about the stow limits.
The 30 cm is there to let heat leave the stow, not to let air in
A self-heating cargo invites packing tight to starve it of oxygen. SP 978.6 overrides that: it requires empty space above the cargo. Charcoal insulates, so heat that cannot leave the stow is the failure mode — the space is ventilation in that sense only. Its cube cost sits in the payload each shape actually achieves in a 20 ft and a 40 ft.
The headspace binds; the stack height limit is the clause's softer half
SP 978.6 is one provision with two halves, graded differently: the 30 cm headspace shall be maintained, while the stow should stay under 1.5 m, or in 16 m³ blocks 15 cm apart. CINS puts it plainly — the headspace holds "whatever approach to packing is adopted", the rest being "additional recommendations" (September 2024). A summary carrying the 30 cm and stopping reproduces half a clause, leaving a packer no stow geometry.
The stuffing day in order: release, reading, stow, seal
No source prescribes a sequence; this is the order at this factory:
- Material leaves weathering only after its period has run — the clock starts at pyrolysis. This factory holds ≥14 days after production, ≥28 days total from raw-material receipt. Bags waiting outside stay dry: wetting releases heat.
- Its temperature is read and recorded before loading.
- The empty box is checked sound, clean, free of residues and pests.
- The stow is built and secured — 20 ft floor-loaded, 40 ft too by preference, or on 20 ISPM-15 pallets — bottom bags uncrushed.
- The 30 cm headspace is measured against the closed stow.
- Readings and dates go into the batch log.
- The doors are sealed, the seal number recorded.
The 40 °C applies to the material, not the ambient; the report records the packing-day mean
The ceiling is a property of the charcoal, not of the air in the yard. CINS strongly recommends a thermal camera on every packaging, and the weathering report records a mean for the day — more than one reading (September 2024). This factory checks the material each stuffing day and measures 20–30 °C against the 40 °C limit. A reading over it stops packing, so on an equatorial floor the hour is a control against a cut-off in sailing schedules and port-pair transit from Indonesia.
Where each reading lands: batch log, weathering report, dangerous-goods declaration
The reading does not stay in the yard: it goes into this factory's batch log with the production and packing dates; those three then go on the dangerous-goods declaration, declaring the load in 4G fibreboard boxes as UN 1361, Class 4.2, PG III. The weathering report carries the same set — CINS asks for those dates, packaging type and the packing-day mean — on Coco Reina letterhead, signed by Mohamad Sinno. A carrier's DG desk reads it at booking; a surveyor checks it. Whose declaration it is depends on the term, where how FOB, CIF and EXW split the dangerous-goods duty is settled.
Stuffing evidence a buyer can request, and what an inability to produce it means
An importer can test a stuffing claim with four specific requests:
| Request | What it proves | If absent |
|---|---|---|
| Weathering report | The period ran; carries the packing-day mean | Four fields separate record from letter |
| Temperature on the DGD | It reached the carrier’s document | Internal, or never taken |
| Vanning survey report | An independent party saw the stow | Nobody outside saw it |
| Seal number | The stow surveyed is the one that sailed | Packing-to-carriage chain unevidenced |
A record that cannot be produced was not kept. Coco Reina supplies the weathering record and vanning survey on request — the records behind how stuffing records are reused in a cargo claim or demurrage dispute. To talk through a loading plan: WhatsApp +628213924038.
Accurate as of July 2026. Special Provision 978 is quoted from the CINS / IG P&I / TT Club "Guidelines for the Safe Carriage of Charcoal in Containers" (September 2024), reproducing IMDG Amendment 42-24, mandatory since 1 January 2026. Carrier conditions change independently of the Code — confirm current requirements with your carrier and forwarder before booking.