49 CFR §172.101 + DOT ERG2024

Hazmat UN Number Lookup

Search by UN number or material name to get the proper shipping name, hazard class, packing group, placard/label codes, and the DOT ERG2024 emergency-response guide number — the same fields dispatchers and drivers check before a hazmat load moves.

Search UN number or material name

Try:

Start typing a UN number (e.g. 1203 or UN1203) or a material name (e.g. gasoline) to search the embedded table.

Hazard class quick reference

Class	Category	Example
1	Explosives (1.1–1.6)	Diazodinitrophenol
2.1	Flammable gas	Propane, butane, hydrogen
2.2	Non-flammable, non-toxic gas	Nitrogen, oxygen, CO₂
2.3	Toxic gas	Chlorine, ammonia, phosgene
3	Flammable liquid	Gasoline, diesel, ethanol
4.1	Flammable solid	Sulfur, matches
4.2	Spontaneously combustible	White phosphorus
4.3	Dangerous when wet	Sodium, calcium carbide
5.1	Oxidizer	Ammonium nitrate, chlorates
5.2	Organic peroxide	Benzoyl peroxide formulations
6.1	Toxic (poison)	Methanol, pesticides
6.2	Infectious substance	Clinical/biological samples
7	Radioactive	UF₆, medical isotopes
8	Corrosive	Sulfuric acid, sodium hydroxide
9	Miscellaneous	Lithium batteries, dry ice, PCBs

Source: Hazard class, packing group, and label data reflect the 49 CFR §172.101 Hazardous Materials Table; emergency-response guide numbers reflect the DOT/PHMSA Emergency Response Guidebook (ERG2024). This tool embeds — common entries as a quick-reference subset — it is not the full table (the full table has thousands of entries covering isomers, concentration bands, and mode-specific variants). Always verify against the current 49 CFR §172.101 table (eCFR) and the official ERG2024 before shipping, placarding, or responding to an incident.