Transport reference
UN 1558 — Arsenic
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 1558 in ADR 2025 and in 49 CFR 172.101
On the fields below the two tables agree for this number. Special provisions are deliberately absent from this comparison: identical code numbers mean different things in the two systems and are never interchangeable.
| Field | ADR 2025 Table A, Chapter 3.2 | 49 CFR 172.101 eCFR 2026-08-03 |
|---|---|---|
| Proper shipping name | ARSENIC | Arsenic |
| Class or division | 6.1 | 6.1 |
| Packing group | II | II |
| Label codes | 6.1 | 6.1 |
| 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 1558 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 |
|---|---|---|---|---|---|---|
| ARSENIC | 6.1 | T5 | II | 6.1 | 2 | 60 |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 6.1 is “Toxic 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. |
Source: ADR 2025, 1.1.3.6.3 and 1.1.3.6.4 · ECE/TRANS/352 Vol. I (UNECE).
Carriage provisions — CV codes
| CV13 | Any leaked/spilled substance must be cleaned up before the unit is reused. |
| CV28 | Must be segregated from foodstuffs, other consumables and animal feed (7.5.4). · relevant to segregation on the vehicle |
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 1558 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) |
|---|---|---|---|---|---|---|---|
| — | Arsenic | 6.1 | II | 6.1 | §173.153 · §173.212 · §173.242 | 25 kg passenger 100 kg cargo | A |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 6.1 is “Poisonous materials” (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.
| IB8 | Authorized IBCs: Metal (11A, 11B, 11N, 21A, 21B, 21N, 31A, 31B and 31N); Rigid plastics (11H1, 11H2, 21H1, 21H2, 31H1 and 31H2 ); Composite (11HZ1, 11HZ2, 21HZ1, 21HZ2 and 31HZ1); Fiberboard (11G); Wooden (11C, 11D and 11F); Flexible (13H1, 13H2, 13H3, 13H4, 13H5, 13L1, 13L2, 13L3, 13L4, 13M1 or 13M2). |
| IP2 | When IBCs other than metal or rigid plastics IBCs are used, they must be offered for transportation in a closed freight container or a closed transport vehicle. |
| IP4 | Flexible, fiberboard or wooden IBCs must be sift-proof and water-resistant or be fitted with a sift-proof and water-resistant liner. |
| T3 | 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)(2). See 49 CFR 172.102(c)(7)(ii), Table of Portable Tank T Codes T1-T22. |
| TP33 | The portable tank instruction assigned for this substance applies for granular and powdered solids and for solids which are filled and discharged at temperatures above their melting point which are cooled and transported as a solid mass. Solid substances transported or offered for transport above their melting point are authorized for transportation in portable tanks conforming to the provisions of portable tank instruction T4 for solid substances of packing group III or T7 for solid substances of packing group II, unless a tank with more stringent requirements for minimum shell thickness, maximum allowable working pressure, pressure-relief devices or bottom outlets are assigned in which case the more stringent tank instruction and special provisions shall apply. Filling limits must be in accordance with portable tank special provision TP3. Solids meeting the definition of an elevated temperature material must be transported in accordance with the applicable requirements of this subchapter. |
Source: 49 CFR 172.102 special provisions · eCFR, revision 2026-08-03
04 · Orange plate
The orange-coloured plate for UN 1558
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.
60 — toxic or slightly toxic substance.
| 6 | Toxicity or risk of infection |
| 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 1558
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 1558 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 1558
| H301 | Toxic if swallowed. |
| H331 | Toxic if inhaled. |
| H400 | Very toxic to aquatic life. |
| H410 | Very toxic 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 1558 — frequently asked questions
What is UN 1558?
UN 1558 is the United Nations number for Arsenic. Under ADR 2025 it is assigned to class 6.1 (toxic substances), classification code T5.
What packing group is UN 1558?
Under ADR 2025 UN 1558 is packing group II.
Is UN 1558 classified the same way in the United States and in Europe?
On the fields we hold — proper shipping name, class, packing group and label codes — ADR 2025 and the 49 CFR 172.101 table agree for UN 1558. Special provisions still differ and are never interchangeable between the two systems.
What is the hazard identification number for UN 1558?
The orange-coloured plate for UN 1558 carries the hazard identification number 60 above the UN number. Under ADR 5.3.2.3.2 that number means: toxic or slightly toxic substance.
What is the transport category of UN 1558?
Column (15) of Table A puts UN 1558 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 1558?
We hold 1 substance linked to UN 1558 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.