9 Classes of Hazardous Materials Assign By US DOT

The U.S. Department of Transportation (DOT) classifies hazardous materials into nine classes based on their characteristics and the potential risks they pose during transportation, as outlined in the Hazardous Materials Regulations (HMR) under Title 49 of the Code of Federal Regulations (CFR). Here is an overview of the nine classes along with specific examples:

9 Classes of Hazardous Materials Assign By US DOT

Class 1: Explosives

Division 1.1: Substances and articles that have a mass explosion hazard.

Example - TNT (Trinitrotoluene): A powerful explosive used in military and industrial applications, known for its mass explosion hazard.

Division 1.2: Substances and articles with a projection hazard but not a mass explosion hazard.

Example - Ammunition: Bullets, shells, and explosive devices with a projection hazard but not a mass explosion hazard.

Division 1.3: Substances and articles with a fire hazard and either a minor blast hazard or a minor projection hazard or both.

Example - Fireworks: Pyrotechnic devices with a fire hazard and minor blast or projection hazards, commonly used for entertainment.

Division 1.4: Substances and articles that present no significant hazard.

Example - Consumer fireworks: Small, safe fireworks for personal use that present no significant hazard.

Division 1.5: Very insensitive substances with a mass explosion hazard.

Example - Detonating cord: A flexible cord filled with explosives, used for controlled blasting, characterized by its mass explosion hazard.

Division 1.6: Extremely insensitive articles that do not have a mass explosion hazard.

Example - Safety fuses: Ignition systems for explosives that are extremely insensitive.

Class 2: Gases

Division 2.1: Flammable gases.

Example - Propane: A flammable gas used for heating and cooking, posing a flammable hazard.

Division 2.2: Non-flammable, non-toxic gases.

Example - Nitrogen: A non-flammable, non-toxic gas commonly used in various industrial processes.

Division 2.3: Toxic gases.

Example - Chlorine: A toxic gas used in industrial applications, presenting a toxic hazard.

Class 3: Flammable Liquids

Example - Gasoline: A highly flammable liquid fuel commonly used in internal combustion engines.

Class 4: Flammable Solids

Division 4.1: Flammable solids.

Example - Magnesium: A highly flammable metal used in industrial processes, presenting a flammable hazard.

Division 4.2: Spontaneously combustible materials.

Example - Phosphorus: A spontaneously combustible material that can ignite in the presence of air.

Division 4.3: Dangerous when wet materials.

Example - Sodium: A dangerous when wet material that reacts violently with water.

Class 5: Oxidizers and Organic Peroxides

Division 5.1: Oxidizers.

Example - Ammonium Nitrate: An oxidizing substance commonly used in fertilizers.

Division 5.2: Organic peroxides.

Example - Benzoyl Peroxide: An organic peroxide used in the production of plastics.

Class 6: Toxic and Infectious Substances

Division 6.1: Toxic substances.

Example - Cyanide: A highly toxic substance used in various industrial processes.

Division 6.2: Infectious substances.

Example - Medical Waste: Materials that can cause diseases in humans or animals, requiring special handling and disposal.

Class 7: Radioactive Materials

Materials that emit ionizing radiation.

Example - Uranium Hexafluoride: Used in the nuclear fuel cycle, emitting ionizing radiation.

Class 8: Corrosive Materials

Substances that can cause severe damage to living tissue, containers, or other materials.

Example - Lead and Sulfuric Acid: highly corrosive substances used in lead-acid autotmotive batteries and various industrial processes.

Class 9: Miscellaneous Hazardous Materials

Hazardous materials that do not fit into the other eight classes, including environmentally hazardous substances, elevated temperature materials, and other miscellaneous items.

Example - Lithium Batteries: Lithium commonly used in automotive batteries and electric vehicles, presenting unique hazards, including the risk of thermal runaway.

It's crucial for those involved in the transportation of hazardous materials to be familiar with these classifications, as they dictate the proper packaging, labeling, and handling requirements to ensure the safety of transportation and those in proximity to the materials. The regulations also provide guidelines for emergency response procedures and documentation.