Key data
| Stowage factor | 0.85–1.00 m³/t (typical 0.92)30.0–35.3 ft³/t (typical 32.5) |
|---|---|
| Form | Bulk |
| IMSBC group | C Cargoes that neither liquefy nor carry a chemical hazard. |
| Angle of repose | ~30 |
| BCSN | AMMONIUM PHOSPHATE |
ft³/t values are per metric tonne (1 m³/t ≈ 35.31 ft³/t). Stowage factors are indicative — see note below.
Description
Diammonium phosphate, or DAP, is a widely traded granular phosphate fertiliser shipped in bulk. At around 0.92 m3/t it is a deadweight cargo. It handles easily as a free-flowing granular product, with its main concerns being moisture, caking and a tendency to give off ammonia.
Stowage & loading
Holds are presented clean and dry, and the granules are loaded by conveyor or grab and trimmed level. Keeping the cargo dry is the priority, as DAP is hygroscopic and absorbs moisture readily, and clean holds prevent contamination of a product destined for agriculture.
Hazards & handling
DAP is hygroscopic and cakes or sets hard if it takes up moisture, complicating discharge, and it can release a pungent ammonia odour, particularly if damp or warm, so spaces are ventilated and entered with care. It is mildly corrosive when wet, so contact with steel is limited.
Carriage & discharge
The cargo is kept dry and well ventilated to limit moisture pickup and ammonia build-up, with spaces tested before entry. Discharge is by grab; any caked material is broken out, and holds are washed down afterwards to remove the mildly corrosive, hygroscopic residue.
Key hazards
- Caking and setting hard if the cargo takes up moisture
- Pungent ammonia evolution, especially when damp or warm
- Mild corrosivity to steel when wet
Loading precautions
- Present clean, dry holds and keep the cargo dry throughout
- Ventilate spaces and test before entry against ammonia
- Wash down holds after discharge to remove corrosive residue
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.