Hazard Classes

For purposes of transportation and shipping, federal regulations assign each hazardous material to one of the following nine hazard classes. The following list provides examples of items that are subject to mailing restrictions

or prohibitions.

• Class 1: Explosives

Fireworks, ammunition, fuses, model rocket engines

• Class 2: Gases

Aerosols, air bag inflators, scuba tanks, butane, propane

• Class 3: Flammable Liquids

Gasoline, some paints or inks, varnishes, some cosmetics, perfumes, lighters and propane cylinders, and items containing fuel or fuel residue

• Class 4: Flammable Solids

Matches, signal flares

• Class 5: Oxidizers and Organic Peroxides

Oxidizing liquids, nitrates, swimming pool chemicals, peroxides

• Class 6: Toxic Materials and Infectious Substances

Arsenic, potassium cyanide, parathion, pesticides, flea collars, tear gas, irritating materials, items containing etiologic agents, used sharps, used medical devices

• Class 7: Radioactive Materials

Scientific instruments, products requiring a radioactive warning label

• Class 8: Corrosives

Chlorine bleach, ammonia, batteries, drain cleaners, acids, mercury, muriatic acid

• Class 9: Miscellaneous Hazardous Materials

Magnetized materials, dry ice, self-inflating lifesaving devices, lithium and lithium-ion batteries