Transport reference
UN 2790 — Acetic acid solution, not less than 50 % but not more than 80 % acid, by mass
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 2790 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 | ACETIC ACID SOLUTION, not less than 50 % but not more than 80 % acid, by mass · ACETIC ACID SOLUTION, more than 10 % and less than 50 % acid, by mass | Acetic acid solution, not less than 50 percent but not more than 80 percent acid, by mass · Acetic acid solution, with more than 10 percent and less than 50 percent acid, by mass |
| Class or division | 8 | 8 |
| Packing group | II, III | II, III |
| Label codes | 8 | 8 |
| Rows in the table | 2 | 2 |
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 2790 in Table A of ADR 2025
2 separate rows in Table A of Chapter 3.2. They are not interchangeable: the packing group follows from the properties of the consignment, and each row carries its own transport category — that is a different multiplier in the 1.1.3.6 calculation.
| Proper shipping name (3.1.2) | Class | Classification code | PG | Labels | Transport category | Hazard ID |
|---|---|---|---|---|---|---|
| ACETIC ACID SOLUTION, not less than 50 % but not more than 80 % acid, by mass | 8 | C3 | II | 8 | 2 | 80 |
| ACETIC ACID SOLUTION, more than 10 % and less than 50 % acid, by mass | 8 | C3 | III | 8 | 3 | 80 |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 8 is “Corrosive substances” (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. |
| 3 | 1 000 | × 1 | Packing group III 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 597 | Acetic acid solutions with not more than 10 % pure acid by mass, are not subject to the requirements of ADR. |
| SP 647 | The carriage of vinegar and acetic acid food grade with not more than 25 % pure acid by mass is subject only to the following requirements: (a) Packagings, including IBCs and large packagings, and tanks shall be manufactured from stainless steel or plastic material which is permanently resistant to corrosion of vinegar/acetic acid food grade; (b) Packagings, including IBCs and large packagings, and tanks shall be subjected to a visual inspection by the owner at least once a year. The results of the inspections shall be recorded and the records kept for at least one year. Damaged packagings, including IBCs and large packagings, and tanks shall not be filled; (c) Packagings, including IBCs and large packagings, and tanks shall be filled in a way that no product is spilled or adheres to the outer surface; (d) Seals and closures shall be resistant to vinegar/acetic acid food grade. Packagings, including IBCs and large packagings, and tanks shall be hermetically sealed by the packer or the filler so that under normal conditions of carriage there will be no leakage; (e) Combination packagings with inner packaging made of glass or plastic (see packing instruction P001 in 4.1.4.1) which fulfil the general packing requirements of 4.1.1.1, 4.1.1.2, 4.1.1.4, 4.1.1.5, 4.1.1.6, 4.1.1.7 and 4.1.1.8 may be used; The other provisions of ADR do not apply. |
Source: ADR 2025, Chapter 3.3 special provisions · ECE/TRANS/352 Vol. I (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 2790 in the 49 CFR 172.101 Hazardous Materials Table
2 separate rows in the Hazardous Materials Table. Where the rows differ only by the symbol in column (1), that symbol is what tells them apart — “D” is domestic-only, “I” is international.
| Symbols (1) | Proper shipping name (2) | Class (3) | PG (5) | Labels (6) | Packaging (8) | Quantity limits (9) | Vessel stowage (10) |
|---|---|---|---|---|---|---|---|
| — | Acetic acid solution, not less than 50 percent but not more than 80 percent acid, by mass | 8 | II | 8 | §173.154 · §173.202 · §173.242 | 1 L passenger 30 L cargo | A · 53, 58 |
| — | Acetic acid solution, with more than 10 percent and less than 50 percent acid, by mass | 8 | III | 8 | §173.154 · §173.203 · §173.242 | 5 L passenger 60 L cargo | A · 53, 58 |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 8 is “Corrosive material” (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
| A | May be stowed “on deck” or “under deck” on a cargo vessel or on a passenger vessel. |
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.
| 148 | For domestic transportation, this entry directs to § 173.66 of this subchapter for: a. The standards for transporting a single bulk hazardous material for blasting by cargo tank motor vehicles (CTMV); and b. The standards for CTMVs capable of transporting multiple hazardous materials for blasting in bulk and non-bulk packagings ( i.e., a multipurpose bulk truck). Note: “UN3375, Ammonium nitrate emulsion” and “UN0332, Explosive, blasting, type E or Agent blasting, type E” are subject to the United Nations (UN) Test Series 8(d) (UN/SCETDG/55/INF.27) (IBR, see § 171.7 of this subchapter), otherwise known as the Vented Pipe Test (VPT). |
| A10 | When aluminum or aluminum alloy construction materials are used, they must be resistant to corrosion. |
| A3 | For combination packagings, if glass inner packagings (including ampoules) are used, they must be packed with absorbent material in tightly closed rigid and leakproof receptacles before packing in outer packagings. |
| A7 | Steel packagings must be corrosion-resistant or have protection against corrosion. |
| B2 | MC 300, MC 301, MC 302, MC 303, MC 305, and MC 306 and DOT 406 cargo tanks are not authorized. |
| IB2 | Authorized IBCs: Metal (31A, 31B and 31N); Rigid plastics (31H1 and 31H2); Composite (31HZ1). |
| IB3 | Authorized IBCs: Metal (31A, 31B and 31N); Rigid plastics (31H1 and 31H2); Composite (31HZ1 and 31HA2, 31HB2, 31HN2, 31HD2 and 31HH2). |
| T4 | Portable tank instruction. Minimum test pressure: 2.65 bar; minimum shell thickness (reference steel): § 178.274(d)(2); pressure-relief requirements: Normal; bottom opening requirements: § 178.275(d)(3). See 49 CFR 172.102(c)(7)(ii), Table of Portable Tank T Codes T1-T22. |
| T7 | Portable tank instruction. Minimum test pressure: 4 bar; minimum shell thickness (reference steel): § 178.274(d)(2); pressure-relief requirements: Normal; bottom opening requirements: § 178.275(d)(3). See 49 CFR 172.102(c)(7)(ii), Table of Portable Tank T Codes T1-T22. |
| TP1 | The maximum degree of filling must not exceed the degree of filling determined by the following: |
| TP2 | a. The maximum degree of filling must not exceed the degree of filling determined by the following: |
Source: 49 CFR 172.102 special provisions · eCFR, revision 2026-08-03
04 · Orange plate
The orange-coloured plate for UN 2790
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.
80 — corrosive or slightly corrosive substance.
| 8 | Corrosivity |
| 0 | No further hazard — the first figure alone describes the hazard adequately |
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 2790
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 2790 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 2790
| H226 | Flammable liquid and vapour. |
| H302 | Harmful if swallowed. |
| H314 | Causes severe skin burns and eye damage. |
| H318 | Causes serious eye damage. |
| H412 | Harmful to aquatic life with long lasting effects. |
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 2790 — frequently asked questions
What is UN 2790?
UN 2790 is the United Nations number for Acetic acid solution, not less than 50 % but not more than 80 % acid, by mass. Under ADR 2025 it is assigned to class 8 (corrosive substances), classification code C3.
What packing group is UN 2790?
Table A of ADR 2025 lists UN 2790 under 2 packing groups — II, III — as separate rows. The packing group follows from the properties of the specific consignment; it is not interchangeable, and each row carries its own transport category.
Is UN 2790 classified the same way in the United States and in Europe?
No. For UN 2790 the two tables differ on proper shipping name. 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 2790?
The orange-coloured plate for UN 2790 carries the hazard identification number 80 above the UN number. Under ADR 5.3.2.3.2 that number means: corrosive or slightly corrosive substance.
Which substances ship under UN 2790?
We hold 2 substances linked to UN 2790 by CAS number, 1 of which also has a full safety data sheet on this site. 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.