Hazmat Class Lookup
Dangerous goods are grouped into nine hazard classes under the UN Model Regulations and US DOT 49 CFR, with divisions for explosives, gases, flammable solids, oxidizers, and toxics. This reference shows each class and division, its definition, common commodities, and the placard used, so you can flag regulated freight before it reaches the dock.
| 1.1 | Explosives | Mass explosion hazard | Dynamite, TNT | Orange, Class 1 |
| 1.4 | Explosives | Minor explosion hazard | Consumer fireworks, ammunition | Orange, Class 1.4 |
| 2.1 | Flammable gas | Ignites in air at 13 percent or less | Propane, butane, hydrogen | Red, Class 2 |
| 2.2 | Non-flammable gas | Compressed or refrigerated gas | Nitrogen, helium, CO2 | Green, Class 2 |
| 2.3 | Toxic gas | Toxic by inhalation | Chlorine, ammonia (anhydrous) | White, skull symbol |
| 3 | Flammable liquid | Flash point at or below 60 C | Gasoline, ethanol, paint | Red, Class 3 |
| 4.1 | Flammable solid | Readily combustible solid | Matches, sulfur | Red and white stripes |
| 4.2 | Spontaneously combustible | Self-heating or pyrophoric | White phosphorus, oily rags | Red and white half |
| 4.3 | Dangerous when wet | Emits flammable gas with water | Calcium carbide, sodium | Blue, Class 4 |
| 5.1 | Oxidizer | Yields oxygen, intensifies fire | Hydrogen peroxide, nitrates | Yellow, flame over circle |
| 5.2 | Organic peroxide | Thermally unstable oxidizer | Benzoyl peroxide | Red and yellow |
| 6.1 | Toxic substance | Poisonous by ingestion or contact | Pesticides, cyanide | White, skull symbol |
| 6.2 | Infectious substance | Contains pathogens | Medical and diagnostic specimens | White, biohazard symbol |
| 7 | Radioactive material | Emits ionizing radiation | Medical isotopes, uranium | Yellow and white, trefoil |
| 8 | Corrosive | Destroys skin or metal | Sulfuric acid, sodium hydroxide | Black and white |
| 9 | Miscellaneous | Other regulated dangerous goods | Lithium batteries, dry ice, magnetized material | Black and white stripes |
Click any column header to sort, and use the filter row to narrow results. Reference dataset for quick lookups. Always verify against the carrier or official source before contractual use.
Frequently Asked Questions
What class are lithium batteries?
Lithium ion and lithium metal batteries are Class 9 miscellaneous dangerous goods, with specific packing instructions, state-of-charge limits, and marking requirements by mode.
Do I need a hazmat placard for every shipment?
Placarding depends on class and quantity. Some materials require placards at any amount, while others only above 454 kg aggregate gross weight. Check 49 CFR 172 Subpart F for your commodity.