Office Of Environmental Health & Safety

Northeastern University
360 Huntington Avenue
170 Cullinane Hall
Boston, MA 02115-5000

phone: 617.373.2769
fax: 617.373.7622 Image 2

Hazardous Material Definition

DOT Definition of Hazardous Material:

A hazardous material is defined as any substance or material could adversely affect the safety of the public, handlers or carriers during transportation. All DOT hazardous materials are listed in the DOT's Hazardous Material Table.

There are nine classes of hazardous materials:

Hazard Class 1: Explosives 1.1 mass explosion hazard
1.2 projectile hazard
1.3 minor blast/projectile/fire
1.4 minor blast
1.5 insensitive explosives
1.6 very insensitive explosives
Hazard Class 2: Compressed Gases 2.1 flammable gases
2.2 non flammable compressed
2.3 poisonous
Hazard Class 3: Flammable Liquids Flammable (flash point below 141°)
Combustible (flash point 141°-200°
Hazard Class 4: Flammable Solids 4.1 flammable solids
4.2 spontaneously combustible
4.3 dangerous when wet
Hazard Class 5: Oxidizers and Organic Peroxides 5.1 Oxidizer
5.2 Organic Peroxide
Hazard Class 6: Toxic Materials 6.1 Material that is poisonous
6.2 Infectious Agents
Hazard Class 7: Radioactive Material Radioactive I
Radioactive II
Radioactive III
Hazard Class 8: Corrosive Material Destruction of the human skin
Corrode steel at a rate of 0.25 inches per year
Hazard Class 9: Miscellaneous A material that presents a hazard during shipment but does not meet the definition of the other classes