Match a rail car, road trailer, or intermodal marking to the ERG 2024 emergency response guide. Categories are transcribed from the official identification charts on pages 10-21. Use only as a last resort - always verify from shipping papers, train consist, or dispatch first.
ERG 2024 pp. 18-21
Under European and some South American regulations, the top half of an orange panel on intermodal bulk containers carries a 2- or 3-digit hazard identification number. The 4-digit UN identifier is in the bottom half.
Top half: hazard identification (Kemler) - intensifies with doubled digits (33, 66, 88), trailing zero when a single digit is enough (30, 40, 50), and prefix Xmeans “reacts dangerously with water”.
Bottom half: the 4-digit UN identification number.
| Code | Meaning |
|---|---|
| 20 | Asphyxiant gas or gas with no subsidiary hazard |
| 22 | Refrigerated liquefied gas, asphyxiant |
| 223 | Refrigerated liquefied gas, flammable |
| 225 | Refrigerated liquefied gas, oxidizing (fire-intensifying) |
| 23 | Flammable gas |
| 238 | Gas, flammable, corrosive |
| 239 | Flammable gas which can spontaneously lead to violent reaction |
| 25 | Oxidizing (fire-intensifying) gas |
| 26 | Toxic gas |
| 263 | Toxic gas, flammable |
| 265 | Toxic gas, oxidizing (fire-intensifying) |
| 268 | Toxic gas, corrosive |
| 28 | Gas, corrosive |
| 30 | Flammable liquid (flash-point 23–60 °C), or molten flammable liquid/solid above its flash-point, or self-heating liquid |
| 323 | Flammable liquid which reacts with water, emitting flammable gases |
| X323 | Flammable liquid which reacts dangerously with water, emitting flammable gases |
| 33 | Highly flammable liquid (flash-point below 23 °C) |
| 333 | Pyrophoric liquid |
| X333 | Pyrophoric liquid which reacts dangerously with water |
| 336 | Highly flammable liquid, toxic |
| 338 | Highly flammable liquid, corrosive |
| X338 | Highly flammable liquid, corrosive, which reacts dangerously with water |
| 339 | Highly flammable liquid which can spontaneously lead to violent reaction |
| 36 | Flammable liquid (flash-point 23–60 °C), slightly toxic, or self-heating liquid, toxic |
| 362 | Flammable liquid, toxic, which reacts with water, emitting flammable gases |
| X362 | Flammable liquid, toxic, which reacts dangerously with water, emitting flammable gases |
| 368 | Flammable liquid, toxic, corrosive |
| 38 | Flammable liquid (flash-point 23–60 °C), slightly corrosive, or self-heating liquid, corrosive |
| 382 | Flammable liquid, corrosive, which reacts with water, emitting flammable gases |
| X382 | Flammable liquid, corrosive, which reacts dangerously with water, emitting flammable gases |
| 39 | Flammable liquid, which can spontaneously lead to violent reaction |
| 40 | Flammable solid, or self-reactive substance, or self-heating substance, or polymerizing substance |
| 423 | Solid which reacts with water emitting flammable gases (also flammable/self-heating variants) |
| X423 | Solid which reacts dangerously with water emitting flammable gases (also flammable/self-heating variants) |
| 43 | Spontaneously flammable (pyrophoric) solid |
| X432 | Spontaneously flammable (pyrophoric) solid which reacts dangerously with water emitting flammable gases |
| 44 | Flammable solid, in the molten state at an elevated temperature |
| 446 | Flammable solid, toxic, in the molten state at an elevated temperature |
| 46 | Flammable or self-heating solid, toxic |
| 462 | Toxic solid which reacts with water emitting flammable gases |
| X462 | Solid which reacts dangerously with water emitting toxic gases |
| 48 | Flammable or self-heating solid, corrosive |
| 482 | Corrosive solid which reacts with water emitting flammable gases |
| X482 | Solid which reacts dangerously with water emitting corrosive gases |
| 50 | Oxidizing (fire-intensifying) substance |
| 539 | Flammable organic peroxide |
| 55 | Strongly oxidizing (fire-intensifying) substance |
| 556 | Strongly oxidizing (fire-intensifying) substance, toxic |
| 558 | Strongly oxidizing (fire-intensifying) substance, corrosive |
| 559 | Strongly oxidizing (fire-intensifying) substance which can spontaneously lead to violent reaction |
| 56 | Oxidizing substance (fire-intensifying), toxic |
| 568 | Oxidizing substance (fire-intensifying), toxic, corrosive |
| 58 | Oxidizing substance (fire-intensifying), corrosive |
| 59 | Oxidizing substance (fire-intensifying) which can spontaneously lead to violent reaction |
| 60 | Toxic or slightly toxic substance |
| 606 | Infectious substance |
| 623 | Toxic liquid, which reacts with water, emitting flammable gases |
| 63 | Toxic substance, flammable (flash-point 23–60 °C) |
| 638 | Toxic substance, flammable (flash-point 23–60 °C), corrosive |
| 639 | Toxic substance, flammable (flash-point ≤ 60 °C) which can spontaneously lead to violent reaction |
| 64 | Toxic solid, flammable or self-heating |
| 642 | Toxic solid which reacts with water, emitting flammable gases |
| 65 | Toxic substance, oxidizing (fire-intensifying) |
| 66 | Highly toxic substance |
| 663 | Highly toxic substance, flammable (flash-point ≤ 60 °C) — or highly toxic solid, flammable/self-heating |
| 665 | Highly toxic substance, oxidizing (fire-intensifying) |
| 668 | Highly toxic substance, corrosive |
| X668 | Highly toxic substance, corrosive, which reacts dangerously with water |
| 669 | Highly toxic substance which can spontaneously lead to violent reaction |
| 68 | Toxic substance, corrosive |
| 69 | Toxic or slightly toxic substance which can spontaneously lead to violent reaction |
| 70 | Radioactive material |
| 768 | Radioactive material, toxic, corrosive |
| 78 | Radioactive material, corrosive |
| 80 | Corrosive or slightly corrosive substance |
| X80 | Corrosive or slightly corrosive substance which reacts dangerously with water |
| 823 | Corrosive liquid which reacts with water, emitting flammable gases |
| 83 | Corrosive or slightly corrosive substance, flammable (flash-point 23–60 °C) |
| X83 | Corrosive or slightly corrosive substance, flammable (23–60 °C), which reacts dangerously with water |
| 836 | Corrosive or slightly corrosive substance, flammable (23–60 °C) and toxic |
| 839 | Corrosive or slightly corrosive substance, flammable (23–60 °C), which can spontaneously lead to violent reaction |
| X839 | Corrosive or slightly corrosive substance, flammable (23–60 °C), which can spontaneously lead to violent reaction and reacts dangerously with water |
| 84 | Corrosive solid, flammable or self-heating |
| 842 | Corrosive solid which reacts with water, emitting flammable gases |
| 85 | Corrosive or slightly corrosive substance, oxidizing (fire-intensifying) |
| 856 | Corrosive or slightly corrosive substance, oxidizing (fire-intensifying) and toxic |
| 86 | Corrosive or slightly corrosive substance, toxic |
| 88 | Highly corrosive substance |
| X88 | Highly corrosive substance which reacts dangerously with water |
| 883 | Highly corrosive substance, flammable (flash-point 23–60 °C) |
| 884 | Highly corrosive solid, flammable or self-heating |
| 885 | Highly corrosive substance, oxidizing (fire-intensifying) |
| 886 | Highly corrosive substance, toxic |
| X886 | Highly corrosive substance, toxic, which reacts dangerously with water |
| 89 | Corrosive or slightly corrosive substance which can spontaneously lead to violent reaction |
| 90 | Environmentally hazardous substance; miscellaneous dangerous substances |
| 99 | Miscellaneous dangerous substance carried at an elevated temperature |