Transport reference
UN 1033 — Dimethyl ether
Table A of ADR 2025 and the 49 CFR 172.101 Hazardous Materials Table for this number, kept side by side and never merged, plus the CLP label elements of the substances that ship under it.
The two tables are never merged. The same UN number can carry a different packing group, a different proper shipping name and entirely different special provisions in each system. Every value below sits under the name of the jurisdiction it comes from.
01 · Two jurisdictions
UN 1033 in ADR 2025 and in 49 CFR 172.101
The two systems differ for this number on 1 of 5 fields. Special provisions are deliberately absent from this comparison: identical code numbers mean different things in the two systems.
| Field | ADR 2025 Table A, Chapter 3.2 | 49 CFR 172.101 eCFR 2026-08-03 |
|---|---|---|
| Proper shipping name | DIMETHYL ETHER | Dimethyl ether |
| Class or division | 2 | 2.1 |
| Packing group | — | — |
| Label codes | 2.1 | 2.1 |
| Rows in the table | 1 | 1 |
Sources: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE) · 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03
02 · ADR 2025
UN 1033 in Table A of ADR 2025
One row in Table A of Chapter 3.2. Every value below comes from that row.
| Proper shipping name (3.1.2) | Class | Classification code | PG | Labels | Transport category | Hazard ID |
|---|---|---|---|---|---|---|
| DIMETHYL ETHER | 2 | 2F | — | 2.1 | 2 | 23 |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 2 is “Gases” (ADR 2.1.1.1).
Transport category and the 1 000-point exemption
Column (15) of Table A decides whether a load stays under the exemption of ADR 1.1.3.6. Quantities of different categories are added with the multipliers below, and the sum must not exceed 1 000.
| Category | Max total quantity per transport unit | Multiplier in 1.1.3.6.4 | What it means |
|---|---|---|---|
| 2 | 333 | × 3 | Packing group II and the listed classes. |
Source: ADR 2025, 1.1.3.6.3 and 1.1.3.6.4 · ECE/TRANS/352 Vol. I (UNECE).
Special provisions — ADR 2025, Chapter 3.3
Codes from column (6) of Table A, with the text of Chapter 3.3.1. These are ADR provisions only. A code with the same number exists in 49 CFR 172.102 and means something else there — the two lists are never combined.
| SP 662 | Cylinders not conforming to the provisions of Chapter 6.2 which are used exclusively on board a ship or aircraft, may be carried for the purpose of filling or inspection and subsequent return, provided the cylinders are designed and constructed in accordance with a standard recognized by the competent authority of the country of approval and all the other relevant requirements of ADR are met including: (a) The cylinders shall be carried with valve protection in conformity with 4.1.6.8; (b) The cylinders shall be marked and labelled in conformity with 5.2.1 and 5.2.2; and (c) All the relevant filling requirements of packing instruction P200 of 4.1.4.1 shall be complied with. The transport document shall include the following statement: "Carriage in accordance with special provision 662". |
Source: ADR 2025, Chapter 3.3 special provisions · ECE/TRANS/352 Vol. I (UNECE)
Carriage provisions — CV codes
| CV10 | Cylinders must be laid parallel or at right angles to the axis and secured. |
| CV36 | Preferably loaded in open or ventilated vehicles; if closed, warning about ventilation before entry. · relevant to segregation on the vehicle |
| CV9 | Packages must not be thrown or subjected to impact. |
Source: ADR 2025, 7.5.11 · ECE/TRANS/352 Vol. II (UNECE)
Not imported and therefore not shown for this number: limited quantities (column 7a), excepted quantities (7b), packing instructions (8), tank codes (10–13) and the tunnel restriction code (15). An empty section is more honest than borrowed text.
03 · United States
UN 1033 in the 49 CFR 172.101 Hazardous Materials Table
One row in the Hazardous Materials Table.
| Symbols (1) | Proper shipping name (2) | Class (3) | PG (5) | Labels (6) | Packaging (8) | Quantity limits (9) | Vessel stowage (10) |
|---|---|---|---|---|---|---|---|
| — | Dimethyl ether | 2.1 | — | 2.1 | §173.306 · §173.304 · §173.314, 315 | Forbidden passenger 150 kg cargo | B · 40 |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 2.1 is “Flammable gas” (49 CFR 173.2). Packaging cells are section references into 49 CFR part 173: exceptions, non-bulk, bulk. Handling codes in column 10B are defined in 49 CFR 176.84, which is not part of our import — the numbers are shown as printed in the table.
Vessel stowage categories on this entry
| B | May be stowed “on deck” or “under deck” on a cargo vessel and on a passenger vessel carrying not more than 25 passengers (or one per 3 m of vessel length); “on deck only” on passenger vessels above that limit. |
Source: 49 CFR 172.101(k) · eCFR, revision 2026-08-03
Special provisions — 49 CFR 172.102
Codes from column (7) of the Hazardous Materials Table, with the text of § 172.102. These are United States provisions only and have nothing to do with the ADR codes above, even where the number is identical.
| T50 | When portable tank instruction T50 is indicated in Column (7) of the § 172.101 Hazardous Materials Table, the applicable liquefied compressed gas and chemical under pressure descriptions are authorized to be transported in portable tanks in accordance with the requirements of § 173.313 of this subchapter. |
Source: 49 CFR 172.102 special provisions · eCFR, revision 2026-08-03
04 · Orange plate
The orange-coloured plate for UN 1033
The upper half of the plate carries the hazard identification number, the lower half the UN number. Dimensions follow ADR 5.3.2.2.1: 400 × 300 mm, black border and dividing line 15 mm, figures 100 mm high.
23 — flammable gas.
| 2 | Emission of gas due to pressure or to chemical reaction |
| 3 | Flammability of liquids (vapours) and gases or self-heating liquid |
Source: ADR 2025, 5.3.2.3 · ECE/TRANS/352 Vol. II (UNECE). The tunnel restriction code of column (15) is a different value and is not part of our import.
05 · Substances
Substances shipped under UN 1033
Linked by CAS number, never by name: a name match once produced “acetone cyanohydrin” for acetone, and a wrong link here would be a wrong classification. Each entry opens its own reference page with the CLP classification and label elements.
06 · The label side
What UN 1033 looks like on a workplace label
The tables above are the transport classification. This is the other half of the same material: the CLP label elements of the substances linked to this number — what actually goes on the drum once it has been delivered. Transport marks and supply labels answer different regulations and do not replace one another.
Hazard statements on the substances under UN 1033
| H220 | Extremely flammable gas. |
Source: harmonised classification, EU CLP Annex VI. Transport classification and supply classification are decided under different rules and do not have to agree.
07 · FAQ
UN 1033 — frequently asked questions
What is UN 1033?
UN 1033 is the United Nations number for Dimethyl ether. Under ADR 2025 it is assigned to class 2 (gases), classification code 2F.
Is UN 1033 classified the same way in the United States and in Europe?
No. For UN 1033 the two tables differ on class or division. Each panel on this page shows its own source; values from one system must not be carried over into the other.
What is the hazard identification number for UN 1033?
The orange-coloured plate for UN 1033 carries the hazard identification number 23 above the UN number. Under ADR 5.3.2.3.2 that number means: flammable gas.
What is the transport category of UN 1033?
Column (15) of Table A puts UN 1033 in transport category 2. Under ADR 1.1.3.6.3 the maximum total quantity per transport unit for that category is 333.
Which substances ship under UN 1033?
We hold 1 substance linked to UN 1033 by CAS number. Each one has its own reference page with the CLP classification, GHS pictograms and hazard statements that apply on the label — the workplace side of the same material.
Need the plate, the labels or the placards printed?
The orange plate above is a physical article, and so are the class labels in column (5). Our sister site GHSLabels.com covers printing and suppliers. For the workplace label of the same material, use the GHS label constructor, and browse other numbers in the UN number reference.
Reference aid only. Values are reproduced from ADR 2025 and the 49 CFR 172.101 table as published; the consignor remains responsible for the classification of a specific consignment. Always verify against the current published regulation and the supplier's safety data sheet.