AIS ship and cargo type · Cargo ships
AIS ship type 73: Cargo ship, hazardous category C
Ship type 73 is the cargo ships family, units digit 3: hazardous category C. What it means, what it does not, and how many vessels we can hear sending it right now.
What code 73 means
Dry cargo ships of every kind. AIS does not distinguish a container ship from a bulk carrier, a general cargo ship or a car carrier — all of them are 7x. Any site that labels a vessel "container ship" from AIS alone is taking that from another source.
A units digit of 3 is the operator declaring hazardous category C cargo on board — the standard groups dangerous goods, harmful substances and marine pollutants into categories A to D. It is a voluntary, hand-entered declaration, not a manifest.
Reading the two digits
- Tens digit 7 → the cargo ships family, codes 70–79.
- Units digit 3 → hazardous category C.
- Therefore: Cargo ship, hazardous category C.
Every code in the 70–79 range
| Code | Meaning |
|---|---|
| 70 | Cargo ship |
| 71 | Cargo ship, hazardous category A |
| 72 | Cargo ship, hazardous category B |
| 73 | Cargo ship, hazardous category C |
| 74 | Cargo ship, hazardous category D |
| 75 | Cargo ship, reserved |
| 76 | Cargo ship, reserved |
| 77 | Cargo ship, reserved |
| 78 | Cargo ship, reserved |
| 79 | Cargo ship, no additional information |
What the code is not
The ship-and-cargo type is typed into the transponder by whoever installs or operates it. No authority checks it against the ship’s certificates, and it is broadcast in the static report every six minutes whether or not it is right. It describes what the operator says the vessel is, not what it is doing — that is the job of the navigational status.
For the whole decade structure in one read, see AIS ship type codes explained.