How to read the UN marking on dangerous goods packaging
Packagings for dangerous goods need a design type approval under the international dangerous goods regulations (e.g. ADR for road, RID for rail, the IMDG Code for sea and the ICAO-TI/IATA DGR for air transport). Every approved packaging bears a durable UN marking. It shows which test requirements the design type has passed: type of packaging and material, packing group, relative density or gross mass, test pressure, year of manufacture, state of approval and manufacturer.
The marking describes the packaging, not its contents. Which substance may be carried in which packaging is laid down in the regulations for that substance. The hazards of the contents are shown separately by the labels and marks on the package.
The elements appear in a fixed order, separated by slashes or spaces, on one or more lines:
- 3H1
- Y1.4
- 150
- 24
- D
- BAM 12345-ABC
- UN packaging symbol (on embossed metal packagings the capital letters “UN” may be used instead).
- Packaging code: a numeral for the kind of packaging, letter(s) for the material and, where applicable, a numeral for the category. Here: plastics jerrican with non-removable head.
- Packing group + relative density or mass: X, Y or Z. For liquids it is followed by the relative density (may be omitted if it does not exceed 1.2), for solids or inner packagings by the maximum gross mass in kg.
- Test pressure or “S”: for liquids the hydraulic test pressure in kPa (rounded down to the nearest 10 kPa), for solids or inner packagings the letter S.
- Year of manufacture (last two digits). Plastics drums and jerricans (1H, 3H) also show the month of manufacture, usually as a date clock.
- State authorizing the mark, shown by its distinguishing sign for motor vehicles in international traffic, e.g. D for Germany.
- Manufacturer or other identification specified by the competent authority. In Germany this is BAM (Federal Institute for Materials Research and Testing).
Sample marking for illustration; the approval number is a placeholder.
Decode a UN marking
Slashes, spaces, a leading “UN” and a comma instead of a decimal point are all fine. Partial markings such as “3H1/Y1.4/150” work too.
Prefer to enter it field by field
Reference: all codes and meanings
Numeral: kind of packaging
| Numeral | Kind of packaging |
|---|---|
| 1 | Drum |
| 2 | (reserved) |
| 3 | Jerrican |
| 4 | Box |
| 5 | Bag |
| 6 | Composite packaging (inner receptacle and outer packaging forming an integral unit) |
| 7 | (reserved) |
| 0 | Light gauge metal packaging |
If the code starts with two digits (11, 13, 21, 31), it is an intermediate bulk container (IBC), see below.
Letter: material
| Letter | Material |
|---|---|
| A | Steel (all types and surface treatments) |
| B | Aluminium |
| C | Natural wood |
| D | Plywood |
| F | Reconstituted wood |
| G | Fibreboard |
| H | Plastics material (incl. rubber and other polymeric materials) |
| L | Textile |
| M | Paper, multiwall |
| N | Metal (other than steel or aluminium) |
| P | Glass, porcelain or stoneware |
Composite packagings (numeral 6) carry two letters: first the material of the inner receptacle, then that of the outer packaging, e.g. 6HA1 = plastics receptacle in a steel drum.
All packaging codes with category
The last numeral means different things depending on the packaging: for drums and jerricans 1 stands for a non-removable head and 2 for a removable head; for boxes and bags it describes the design.
| Code | Kind | Material | Category |
|---|---|---|---|
| 1A1 | Drum | Steel | non-removable head |
| 1A2 | Drum | Steel | removable head |
| 1B1 | Drum | Aluminium | non-removable head |
| 1B2 | Drum | Aluminium | removable head |
| 1D | Drum | Plywood | – |
| 1G | Drum | Fibre | – |
| 1H1 | Drum | Plastics | non-removable head |
| 1H2 | Drum | Plastics | removable head |
| 1N1 | Drum | Metal other than steel or aluminium | non-removable head |
| 1N2 | Drum | Metal other than steel or aluminium | removable head |
| 3A1 | Jerrican | Steel | non-removable head |
| 3A2 | Jerrican | Steel | removable head |
| 3B1 | Jerrican | Aluminium | non-removable head |
| 3B2 | Jerrican | Aluminium | removable head |
| 3H1 | Jerrican | Plastics | non-removable head |
| 3H2 | Jerrican | Plastics | removable head |
| 4A | Box | Steel | – |
| 4B | Box | Aluminium | – |
| 4C1 | Box | Natural wood | ordinary |
| 4C2 | Box | Natural wood | with sift-proof walls |
| 4D | Box | Plywood | – |
| 4F | Box | Reconstituted wood | – |
| 4G | Box | Fibreboard | – |
| 4H1 | Box | Plastics | expanded |
| 4H2 | Box | Plastics | solid |
| 4N | Box | Metal other than steel or aluminium | – |
| 5H1 | Bag | Woven plastics | without inner liner or coating |
| 5H2 | Bag | Woven plastics | sift-proof |
| 5H3 | Bag | Woven plastics | water resistant |
| 5H4 | Bag | Plastics film | – |
| 5L1 | Bag | Textile | without inner liner or coating |
| 5L2 | Bag | Textile | sift-proof |
| 5L3 | Bag | Textile | water resistant |
| 5M1 | Bag | Paper | multiwall |
| 5M2 | Bag | Paper | multiwall, water resistant |
| 6HA1 | Composite packaging | Plastics receptacle | in a steel drum |
| 6HA2 | Composite packaging | Plastics receptacle | in a steel crate or box |
| 6HB1 | Composite packaging | Plastics receptacle | in an aluminium drum |
| 6HB2 | Composite packaging | Plastics receptacle | in an aluminium crate or box |
| 6HC | Composite packaging | Plastics receptacle | in a wooden box |
| 6HD1 | Composite packaging | Plastics receptacle | in a plywood drum |
| 6HD2 | Composite packaging | Plastics receptacle | in a plywood box |
| 6HG1 | Composite packaging | Plastics receptacle | in a fibre drum |
| 6HG2 | Composite packaging | Plastics receptacle | in a fibreboard box |
| 6HH1 | Composite packaging | Plastics receptacle | in a plastics drum |
| 6HH2 | Composite packaging | Plastics receptacle | in a solid plastics box |
| 6PA1 | Composite packaging | Glass, porcelain or stoneware receptacle | in a steel drum |
| 6PA2 | Composite packaging | Glass, porcelain or stoneware receptacle | in a steel crate or box |
| 6PB1 | Composite packaging | Glass, porcelain or stoneware receptacle | in an aluminium drum |
| 6PB2 | Composite packaging | Glass, porcelain or stoneware receptacle | in an aluminium crate or box |
| 6PC | Composite packaging | Glass, porcelain or stoneware receptacle | in a wooden box |
| 6PD1 | Composite packaging | Glass, porcelain or stoneware receptacle | in a plywood drum |
| 6PD2 | Composite packaging | Glass, porcelain or stoneware receptacle | in a wickerwork hamper |
| 6PG1 | Composite packaging | Glass, porcelain or stoneware receptacle | in a fibre drum |
| 6PG2 | Composite packaging | Glass, porcelain or stoneware receptacle | in a fibreboard box |
| 6PH1 | Composite packaging | Glass, porcelain or stoneware receptacle | in an expanded plastics packaging |
| 6PH2 | Composite packaging | Glass, porcelain or stoneware receptacle | in a solid plastics packaging |
| 0A1 | Light gauge metal packaging | Steel | non-removable head |
| 0A2 | Light gauge metal packaging | Steel | removable head |
Letters after the code: T = salvage packaging, V = special packaging, W = packaging of the same type made to a different but equivalent specification (e.g. 4HW).
Packing group, relative density, mass and test pressure
| Mark | Meaning |
|---|---|
| X | tested for packing groups I, II and III (high, medium and low danger) |
| Y | tested for packing groups II and III |
| Z | packing group III only |
| Decimal number | for liquids without inner packagings: relative density, rounded to the first decimal (e.g. Y1.4). May be omitted if it does not exceed 1.2; then only the letter is shown (e.g. Y/100). |
| Number + S | for solids or inner packagings: maximum gross mass in kg (e.g. Y60/S = max. 60 kg gross). |
| kPa | for liquids: hydraulic test pressure passed, in kPa, rounded down to the nearest 10 kPa (e.g. 150 = 150 kPa = 1.5 bar). |
A packaging tested for X or Y may also be used for substances of a lower packing group, with a correspondingly higher permitted relative density. The details are given in the test report or approval certificate.
Intermediate bulk containers (IBCs), reconditioning and other marks
IBCs have a two-digit code: 11 = solids, filled or discharged by gravity; 21 = solids, filled or discharged under pressure (more than 10 kPa); 31 = liquids (all rigid); 13 = flexible. Material and, where applicable, category follow, e.g. 31HA1 = composite IBC for liquids with a rigid plastics inner receptacle and a steel outer casing. The order of the elements differs from packagings: code / packing group (no density) / month and year of manufacture / state / manufacturer / stacking test load in kg (0 = not designed for stacking) / maximum permissible gross mass in kg.
Reconditioned packagings additionally show the state, the reconditioner and the year followed by the letter R, plus L if the leakproofness test was passed (e.g. NL/RB/01RL).
REC next to the marking means: made from recycled plastics material.
Period of use: plastics drums and jerricans, rigid plastics IBCs and composite IBCs with a plastics inner receptacle may as a rule be used for dangerous goods for five years from their date of manufacture, unless a shorter period is prescribed for the substance.
Worked example
Marking: UN 1H2/Y60/S/25/D/BAM 23456-ABC (sample marking)
- 1H2: drum (1) made of plastics (H) with removable head (2), i.e. an open-top drum.
- Y60: tested for substances of packing groups II and III, maximum gross mass 60 kg.
- S: for solids or inner packagings.
- 25: manufactured in 2025. On plastics drums the month is also shown in the date clock.
- D: mark authorized in Germany.
- BAM 23456-ABC: BAM approval identification with manufacturer code.
In our range you will find UN-approved packagings among our UN narrow-neck bottles for hazardous materials and our HDPE jerricans. For solid dangerous goods, see our CurTec wide-neck drums with screw lid, our HDPE lidded drums and our square UN wide-neck bottles made of HDPE. The exact approval is stated for each item.
Based on: ADR 2025, sections 6.1.2 (codes), 6.1.3 (marking), 6.5.1.4 and 6.5.2.1 (IBCs) and 4.1.1.15 (period of use); the same rules apply under RID and the UN Recommendations on the Transport of Dangerous Goods (Orange Book). This overview does not replace the approval certificate of the individual packaging.