A UN marking panel is the most information-dense object in this industry and almost nobody reads it. It is also the only thing standing between a legal hazmat shipment and an expensive conversation with an inspector. Here is the whole string, translated.
A worked example
31HA1/Y/26/2104/USA/+AB1234
| Segment | Reads as | Meaning |
|---|---|---|
| 3 | IBC category | Composite IBC |
| 1 | Intended contents | For liquids (1 = liquids; 2 = solids under pressure; others for gravity-discharge solids) |
| H | Material of the inner receptacle | Plastic (A = steel, B = aluminium, N = other metal, D = plywood, G = fibreboard) |
| A1 | Outer construction | Rigid plastic inner with an outer steel frame |
| Y | Packing group | Approved for packing groups II and III |
| 26 | Design / stacking segment | Code applied under the governing test report |
| 2104 | Date of manufacture | Month-year coding identifying when it was built |
| USA | State of authorisation | The competent authority whose approval it holds |
| +AB1234 | Approval / registration code | Identifies the manufacturer or licensed reconditioner |
Packing groups in one line each
- X — approved for packing groups I, II and III. The highest hazard category.
- Y — approved for groups II and III. The most common rating on composite IBCs.
- Z — approved for group III only.
Your safety data sheet states the packing group of your material. A Y-rated tote cannot carry a packing group I substance, however new and clean it looks.
What sits behind the marking
The marking is shorthand for a test regime performed on sample units of that design: drop testing from a height tied to the packing group, leakproofness under internal air pressure, a hydraulic pressure test well above service pressure, a stacking test at a multiple of gross mass sustained over time, bottom and top lift tests, and a vibration test. Periodic retest and inspection obligations then apply to units in regulated service.
Five things that void it instantly
- Replacing the inner bottle outside a licensed reconditioning programme
- Welding, drilling or cutting the cage
- Fitting a valve or closure not covered by the original approval
- Repairing structural damage without re-test and re-marking
- An illegible, painted-over or removed marking panel
After any of these the unit is still a perfectly serviceable tote. It is simply no longer a legal packaging for regulated goods until a licensed reconditioner re-tests and re-marks it. We route that work to a licensed partner, and the resulting paperwork carries their registration — not ours.
The practical advice
Photograph the panel. Every time, on every unit, before you buy and again when it arrives. A lot of used totes is never as uniform as the seller believes, and the panel is the only thing that tells the truth about each individual cage.
If you only store product on site and never offer it for transport, you very likely do not need a UN-rated tote at all, and buying one is a waste of money we will talk you out of. See the UN markings chapter for the condensed reference version of this article.
This is reference material from a reconditioning yard, not regulatory advice. Confirm your specific obligations with your carrier or a dangerous-goods advisor.
