Why hazard labels matter

Dangerous goods must be classified, packed, marked, and documented according to international rules before they can move by sea, air, or road. The hazard label is the most visible signal of what is inside a package. Recognizing the symbols helps shippers, warehouse teams, and carriers handle goods safely and prepare the right paperwork.

Class 1 — Explosives

UN transport label for explosives, Class 1Explosives (Class 1)
UN transport label for Class 1.4 explosives with no significant hazardClass 1.4 — no significant hazard
UN transport label for Class 1.5 very insensitive explosives with a mass explosion hazardClass 1.5 — very insensitive, mass explosion hazard

Class 2 — Gases

UN transport label for flammable gases, Class 2.1Flammable gas (Class 2.1)
UN transport label for non-flammable, non-toxic gases, Class 2.2Non-flammable, non-toxic gas (Class 2.2)

Class 3 — Flammable liquids

UN transport label for flammable liquids, Class 3Flammable liquid (Class 3)

Class 4 — Flammable solids

UN transport label for flammable solids, Class 4.1Flammable solid (Class 4.1)
UN transport label for substances liable to spontaneous combustion, Class 4.2Spontaneously combustible (Class 4.2)
UN transport label for substances which emit flammable gases in contact with water, Class 4.3Dangerous when wet (Class 4.3)

Class 5 — Oxidizing substances and organic peroxides

UN transport label for oxidizing substances and organic peroxides, Class 5Oxidizer / organic peroxide (Class 5.1 / 5.2)

Class 6 — Toxic and infectious substances

UN transport label for toxic substances, Class 6.1Toxic substances (Class 6.1)
UN transport label for infectious substances, Class 6.2Infectious substances (Class 6.2)

Class 7 — Radioactive material

UN transport label for radioactive material, Class 7Radioactive material (Class 7)
UN transport label for radioactive material, category IRadioactive — Category I
UN transport label for radioactive material, category IIRadioactive — Category II
UN transport label for radioactive material, category IIIRadioactive — Category III

Class 8 — Corrosive substances

UN transport label for corrosive substances, Class 8Corrosive substances (Class 8)

Label format

Diagram showing the location of the hazard class number on a UN transport labelLocation of the hazard class number on the label

Important note

This page is a visual reference only. Actual classification, UN number, packing group, packaging, marking, and documentation must follow the current IMDG Code (sea), IATA Dangerous Goods Regulations (air), ADR (road), or the applicable national regulation. Always work with a qualified dangerous goods specialist before shipping hazardous materials.