Everything a handler knows about your cargo, they know from the outside of the package. They do not have the packing list, they cannot read your language, and they are working fast. The marks are the interface.
Marking is also a legal requirement in places people do not expect, and a missing mark can hold a consignment at customs as effectively as a missing document.
Shipping marks
The identifying block on each package, used to route it and to match it against the documents. It is essential for LCL and air consolidations, where your cartons are travelling with everyone else's and nothing else distinguishes them.
A conventional shipping mark carries:
- Consignee name or an agreed code
- Destination port or city
- Package number and total, in the form 3 of 12
- Gross and net weight, and dimensions
- Order or contract reference
- Country of origin
Two disciplines matter more than the format. The marks must match the packing list and the bill of lading exactly, because a customs officer comparing a carton to a document that disagrees will stop the consignment. And old marks must be removed or obliterated when packaging is reused, since a carton bearing two destinations will reliably go to the wrong one.
Handling symbols
Standardised pictograms under ISO 780, which exist because they work regardless of language:
- Fragile, the broken glass
- This way up, two arrows, which must be applied to all four vertical sides or it is not reliable
- Keep dry, the umbrella
- Keep away from heat or sunlight
- Temperature limits, with the range stated
- Do not use hand hooks, which matters for bagged and baled cargo
- Centre of gravity, and sling here
- Stacking limit, by mass or by number of packages, and do not stack
Use few symbols and mean them. A carton covered in fragile stickers is treated the same as one with none, because handlers learn quickly that a shipper who marks everything fragile is not distinguishing anything.
Country of origin marking
A customs requirement rather than a logistics one, and one of the more common causes of avoidable delay. Many countries require imported goods to be marked with their country of origin in a conspicuous, legible and permanent way. In the United States the rule reaches the article itself, not merely the outer carton, for most goods, with specified exceptions.
Get this wrong and the options are marking under customs supervision at your cost, re-export, or a duty penalty. Confirm the destination's rule before production, because it is usually a factory instruction, not a packing bay one. See rules of origin for the related but separate question of which origin to declare.
The UN packaging mark
For dangerous goods in performance tested packaging, the packaging itself carries a certification mark, for example: UN 4G/Y145/S/26/GB/1234.
- UN in a circle, the packaging symbol
- 4G, the packaging type, here a fibreboard box
- Y, the packing group it is certified for, X for I, Y for II, Z for III
- 145, the maximum gross mass in kilograms, or the specific gravity for liquids
- S, meaning solids or inner packagings
- 26, the year of manufacture
- GB, the authorising state, and the manufacturer's code
You cannot make this mark yourself: it certifies that the packaging design passed drop, stack and pressure testing. Using a box with the wrong mark, or an expired one, is a packaging failure. See the dangerous goods declaration.
Practical rules
- Mark at least two opposite sides, never only the top, which is invisible in a stack.
- Use waterproof, fade resistant ink or labels. Ocean freight is a wet, abrasive environment.
- Keep marks off the seams, where tape and strapping cover them.
- Do not mark the value or the brand on the outside of high value cargo. It is an invitation.
- Photograph the marked packages before they leave, alongside the packing list.
