Key data
| Stowage factor | 0.90–1.10 m³/t (typical 0.95)31.8–38.8 ft³/t (typical 33.5) |
|---|---|
| Form | Bulk |
| IMSBC group | C Cargoes that neither liquefy nor carry a chemical hazard. |
| Angle of repose | ~30 |
| BCSN | NPK FERTILIZER |
ft³/t values are per metric tonne (1 m³/t ≈ 35.31 ft³/t). Stowage factors are indicative — see note below.
Description
NPK fertilisers are blended granular products supplying nitrogen, phosphorus and potassium, traded in many formulations. At around 0.95 m3/t they are deadweight cargoes. Most handle as straightforward granular cargo, but grades containing nitrate can decompose, so the specific grade matters.
Stowage & loading
Holds are presented clean and dry, and the granules are loaded by conveyor or grab and trimmed level, with the grade's carriage requirements confirmed first. Dryness and clean holds are the priority, both to prevent caking and to keep nitrate-bearing grades free of contamination.
Hazards & handling
NPK is hygroscopic and cakes if damp. Grades containing nitrate can undergo self-sustaining decomposition if heated – a smouldering reaction that spreads through the stow giving off toxic gases – so heat and contamination are kept away and the grade's classification is respected.
Carriage & discharge
The cargo is kept dry and cool, away from heat sources, with nitrate-bearing grades watched for any sign of heating or fumes. Discharge is by grab, with caked material broken out, and holds cleaned of residue afterwards, especially before loading any sensitive following cargo.
Key hazards
- Caking if the cargo absorbs moisture
- Self-sustaining decomposition of nitrate-bearing grades if heated, giving toxic gas
- Contamination sensitivity in nitrate-bearing grades
Loading precautions
- Confirm the grade's classification and carriage requirements before loading
- Present clean, dry holds and keep the cargo dry and cool
- Keep heat and contaminants away from nitrate-bearing grades
Stowage factors are indicative and vary with grade, origin, moisture and packing. Always verify against the shipper's cargo declaration and the applicable IMSBC Code schedule before fixing or loading. This is general information, not professional or safety advice.