9 Hazmat Classes

Written by Nick Webster

Published on Aug. 13, 2023, 11 a.m.

9 Hazmat Classes

Listed below are the 9 hazmat classes. Hazmat (hazardous materials) classes are divided into 9 categories, each with its own unique characteristics:

1. Class 1: Explosives

2. Class 2: Gases

3. Class 3: Flammable and Combustible Liquids

4. Class 4: Flammable Solids

5. Class 5: Oxidizers and Organic Peroxides

6. Class 6: Toxic and Infectious Substances

7. Class 7: Radioactive Materials

8. Class 8: Corrosive Substances

9. Class 9: Miscellaneous Dangerous Goods (including items such as hazardous waste, dry ice, vehicle batteries, etc.)


Commercial truck driving can open up a range of opportunities, from delivering everyday goods to transporting specialized items. Class 9 hazamat. Among these special cases, Hazardous Materials (Hazmat) transportation stands out for its unique risks and rewards. To ensure the safety of everyone involved, specific regulations and classifications have been established. One of the core components of this system is the classification of hazardous materials into nine distinct classes.

What Are Hazmat Classes?

The United Nations established the nine classes of hazardous materials in an attempt to standardize the handling, transportation, and storage of these substances worldwide. These classes categorize hazardous materials according to the risks they pose, helping transporters, handlers, and first responders to know what they are dealing with, facilitating their safe transport and immediate action in case of an emergency.

What is Class 1: Explosives?

Explosives, forming Class 1, are substances that can detonate or explode due to a chemical reaction. This class is further subdivided into six divisions based on their risk level, ranging from highly explosive substances like dynamite (Division 1.1) to extremely insensitive articles (Division 1.6). Transporting these materials requires careful planning and adherence to stringent safety measures, given their inherent risk.

What is Class 2: Gases?

Class 2 consists of gases, which include flammable gases, non-flammable gases, and toxic gases. Visit & know about Hazmat Carrier. Gases are characterized by their tendency to spread rapidly when released. A unique challenge associated with transporting gases is their high pressure and temperature-based behavior, which demand specialized containment measures. Examples include propane (flammable), helium (non-flammable), and chlorine (toxic).

What is Class 3: Flammable and Combustible Liquids?

Flammable and combustible liquids, forming Class 3, are liquids or mixtures of liquids that emit flammable vapors. The risk here is not from the liquid itself, but rather the vapor it produces. Gasoline and acetone are typical examples. Special attention must be paid to the containment of these substances to prevent vapor release and ignition.

What is Class 4: Flammable Solids?

Class 4 consists of flammable solids, substances prone to spontaneous combustion, and substances that emit flammable gases upon contact with water. How to get an IFTA Sticker. These materials have the potential to ignite easily or undergo violent reactions under certain conditions. Examples include sodium (which reacts with water) and matches (a flammable solid).

What is Class 5: Oxidizing Substances and Organic Peroxides?

Oxidizing substances and organic peroxides make up Class 5. These substances may not burn themselves but can cause or contribute to the combustion of other materials. They include substances such as hydrogen peroxide (an oxidizer) and dibenzoyl peroxide (an organic peroxide). Want to know about BOC-3.The primary risk associated with these substances is their reactive nature, requiring careful handling and storage.

What is Class 6: Toxic and Infectious Substances?

Class 6 consists of toxic and infectious substances. These materials pose a health risk to humans and animals if swallowed, inhaled, or if they come into contact with skin. They range from medical waste (an infectious substance) to pesticides (a toxic substance). These substances demand stringent safety measures and protective equipment during transportation.

What is Class 7: Radioactive Material?

Class 7 comprises radioactive materials. These substances emit ionizing radiation, which can be harmful or fatal to living organisms. Know about FMCSA 30-Minute Break Rule. Radioactive materials are often used in medical or industrial applications, and their transportation requires strict regulatory control and specialized containment measures.

What is Class 8: Corrosive Substances?

Class 8 encompasses corrosive substances, which have the potential to cause significant harm upon contact with living tissue. In the event of leakage, these substances can also inflict damage or destruction on other cargo or the transportation vehicle itself. Know about MCS-150. Examples of corrosive substances include battery acid and bleach. It is crucial for drivers who handle these materials to have a thorough understanding of the associated risks and adhere to the necessary safety protocols to prevent any form of exposure.

What is Class 9: Miscellaneous Hazardous Materials?

Class 9, the final category, is a catch-all for miscellaneous hazardous materials. This class includes any substances that pose a risk during transportation but don't fit into any other class. Examples could be asbestos or environmentally hazardous substances. As this category is diverse, the risks and handling methods can vary significantly.

How Are Hazmat Classes Relevant to Commercial Truck Driving?

Now that we have detailed the different Hazmat classes, let's explore their relevance to commercial truck driving. Driving a commercial truck is not merely about moving goods from point A to point B. It requires a keen understanding of what's being transported, especially when dealing with hazardous materials.

For drivers, the Hazmat classes provide critical information about the nature of the cargo they're carrying. This understanding informs the safety measures that must be in place and the appropriate response should an incident occur. Additionally, it also impacts the licensing requirements for drivers.

Licensing and Hazmat Endorsement

Hazardous materials drivers are required to hold a Commercial Driver's License (CDL) with a Hazardous Materials (H) endorsement. Do you want to know about DOT Clearinghouse Enforcement. This endorsement indicates that a driver has passed the necessary written test on the transportation of hazardous materials. Familiarity with the nine classes of hazardous materials forms a significant portion of this examination.

Moreover, the endorsement process includes a comprehensive security threat assessment performed by the Transportation Security Administration (TSA). A clean driving record and a criminal background check are essential for acquiring this endorsement, emphasizing the high level of responsibility that comes with transporting hazardous materials.

Safety Measures and Emergency Response

The nine Hazmat classes also play a crucial role in defining the safety protocols for the transportation of these materials. Know about Trucking Authority Packages. From the design of the transport containers to the necessary protective equipment and the appropriate placement in the transport vehicle, each class has specific safety guidelines.

In addition, in case of an incident, the nine classes serve as a quick reference for first responders, helping them identify the involved material and the potential risks it poses. This knowledge allows them to employ the correct containment and mitigation strategies swiftly and efficiently, protecting both themselves and the public.

Compliance with Regulations

Compliance with the federal and state regulations for hazardous materials transportation is another aspect where the nine classes play a significant role. How To Request the DOT PIN Number. Non-compliance can lead to severe penalties, including substantial fines and even imprisonment. Drivers are expected to know the rules surrounding the transportation of their specific cargo, from proper packaging and labeling to accurate shipping paperwork.

The Value of Professional Development

The understanding and mastery of the nine Hazmat classes signify a driver’s professional development within the commercial trucking industry. Drivers specializing in hazardous materials transportation often enjoy higher pay rates due to the unique knowledge and skills required. Additionally, they are likely to experience greater job stability due to the continuous demand for their specialized services.


Navigating the nine classes of hazardous materials is crucial for anyone in the commercial trucking industry involved with hazardous materials transport. Want to know about Motor Carrier Authority. This knowledge not only ensures compliance with regulations but also contributes significantly to the safety of the driver, the environment, and the general public. With this understanding, we can appreciate the intricate dynamics involved in the transportation of hazardous materials, reinforcing the role that professional commercial truck drivers play in our society.

Summary: What Are the 9 Hazmat Classes?

- Class 1: Explosives

- Class 2: Gases

- Class 3: Flammable and Combustible Liquids

- Class 4: Flammable Solids, Spontaneously Combustible Materials, and Dangerous When Wet Materials

- Class 5: Oxidizers and Organic Peroxides

- Class 6: Toxic and Infectious Substances

- Class 7: Radioactive Materials

- Class 8: Corrosives

- Class 9: Miscellaneous Dangerous Goods (including miscellaneous hazardous materials such as dry ice, asbestos etc.)