Transport reference
UN 1218 — Isoprene, stabilized
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 1218 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 | ISOPRENE, STABILIZED | Isoprene, stabilized |
| Class or division | 3 | 3 |
| Packing group | I | I |
| Label codes | 3 | 3 |
| 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 1218 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 |
|---|---|---|---|---|---|---|
| ISOPRENE, STABILIZED | 3 | F1 | I | 3 | 1 | 339 |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 3 is “Flammable liquids” (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 |
|---|---|---|---|
| 1 | 20 | × 50 | Packing group I and the listed classes — the exemption runs out after 20 kg or litres per transport unit. |
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 386 | When substances are stabilized by temperature control, the provisions of 2.2.41.1.21, 7.1.7, special provision V8 of Chapter 7.2, special provision S4 of Chapter 8.5 and the requirements of Chapter 9.6 apply. When chemical stabilization is employed, the person offering the packaging, IBC or tank for carriage shall ensure that the level of stabilization is sufficient to prevent the substance in the packaging, IBC or tank from dangerous polymerization at a bulk mean temperature of 50 °C, or, in the case of a portable tank, 45 °C. Where chemical stabilization becomes ineffective at lower temperatures within the anticipated duration of carriage, temperature control is required. In making this determination factors to be taken into consideration include, but are not limited to, the capacity and geometry of the packaging, IBC or tank and the effect of any insulation present, the temperature of the substance when offered for carriage, the duration of the journey and the ambient temperature conditions typically encountered in the journey (considering also the season of year), the effectiveness and other properties of the stabilizer employed, applicable operational controls imposed by regulation (e.g. requirements to protect from sources of heat, including other cargo carried at a temperature above ambient) and any other relevant factors. |
| SP 676 | For the carriage of packages containing polymerizing substances the provisions of special provision 386, in conjunction with 7.1.7.3, 7.1.7.4, 5.4.1.1.15 and 5.4.1.2.3.1, need not be applied, when carried for disposal or recycling provided the following conditions are met: (a) Before loading an examination has shown that there is no significant deviation between the outside temperature of the package and the ambient temperature; (b) The carriage is effected within a period of not more than 24 hours from that examination; (c) The packages are protected from direct sunlight and from the impact of other sources of heat (e.g. additional loads that are being carried above ambient temperature) during carriage; (d) The ambient temperatures during the carriage are below 45 °C; (e) Vehicles and containers are adequately ventilated; (f) The substances are packed in packages with a maximum capacity of 1000 litres. In assessing the substances for carriage under the conditions of this special provision, additional measures to prevent dangerous polymerization may be considered, for example the addition of inhibitors. |
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 1218 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) |
|---|---|---|---|---|---|---|---|
| — | Isoprene, stabilized | 3 | I | 3 | §173.150 · §173.201 · §173.243 | 1 L passenger 30 L cargo | D · 25 |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 3 is “Flammable and combustible liquid” (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
| D | Must be stowed “on deck only” on a cargo vessel or on a passenger vessel within the 25-passenger limit; prohibited on a passenger vessel 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.
| 387 | When materials are stabilized by temperature control, the provisions of § 173.21(f) of this subchapter apply. When chemical stabilization is employed, the person offering the material for transport shall ensure that the level of stabilization is sufficient to prevent the material as packaged from dangerous polymerization at 50 °C (122 °F). If chemical stabilization becomes ineffective at lower temperatures within the anticipated duration of transport, temperature control is required in which case transportation is forbidden by aircraft. In making this determination factors to be taken into consideration include, but are not limited to, the capacity and geometry of the packaging and the effect of any insulation present; the temperature of the material when offered for transport; the duration of the journey and the ambient temperature conditions typically encountered in the journey (considering also the season of year); the effectiveness and other properties of the stabilizer employed; applicable operational controls imposed by regulation ( e.g., requirements to protect from sources of heat, including other cargo carried at a temperature above ambient); and any other relevant factors. |
| T11 | Portable tank instruction. Minimum test pressure: 6 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. |
| 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 1218
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.
339 — highly flammable liquid which can spontaneously lead to violent reaction.
| 3 | Flammability of liquids (vapours) and gases or self-heating liquid |
| 3 | Flammability of liquids (vapours) and gases or self-heating liquid · doubled figure — intensification of that hazard |
| 9 | Risk of spontaneous violent reaction |
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 1218
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 1218 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 1218
| H224 | Extremely flammable liquid and vapour. |
| H341 | Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
| H350 | May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
| 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 1218 — frequently asked questions
What is UN 1218?
UN 1218 is the United Nations number for Isoprene, stabilized. Under ADR 2025 it is assigned to class 3 (flammable liquids), classification code F1.
What packing group is UN 1218?
Under ADR 2025 UN 1218 is packing group I.
Is UN 1218 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 1218. Special provisions still differ and are never interchangeable between the two systems.
What is the hazard identification number for UN 1218?
The orange-coloured plate for UN 1218 carries the hazard identification number 339 above the UN number. Under ADR 5.3.2.3.2 that number means: highly flammable liquid which can spontaneously lead to violent reaction.
What is the transport category of UN 1218?
Column (15) of Table A puts UN 1218 in transport category 1. Under ADR 1.1.3.6.3 the maximum total quantity per transport unit for that category is 20.
Which substances ship under UN 1218?
We hold 1 substance linked to UN 1218 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.