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Classifying Hazardous Materials

Hazardous Materials

Take some time to familiarize yourself with the standard nine classes of hazardous materials.

Understanding the classification of hazardous waste is critical for almost any workplace. Regardless of whether you’re working in an office or a factory, it’s likely that there are hazardous materials in your facility that you and your staff need to know how to identify and deal with. There are nine classes of hazardous materials as designated by the United States Department of Transportation or USDOT.

Explosives: Class 1 

Divided into six sub-sections, the explosives category includes materials that rapidly conflagrate or detonate after a chemical reaction. This category includes materials like airbag inflators, fireworks, and ammunition. 

Gases: Class 2 

Compressed gases, aerosols, gas cartridges, fire extinguishers, natural gas, and propane all fall into the second class of hazard. This can also include materials with a vapor pressure of 300kPa or greater. 

Flammable Liquids: Class Three 

If a material has a flashpoint of 60º Celsius or lower it is included in class three. Some of the most common examples include acetone, gasoline, paint, adhesives, and diesel fuel. 

Flammable Solids: Class Four 

Sodium batteries, metal powders, matches, and activated carbon all make up some examples of class four, which is materials that a solid yet can quickly catch fire. These materials are also considered ones that can easily combust under routine conditions. 

Oxidizing Substances: Class Five 

Class five includes substances that can contribute to or cause combustion because they yield oxygen during a chemical reaction. These often include materials such as nitrates, ammonium nitrate, and sodium nitrate. 

Toxic and Infectious Substances: Class Six 

These materials can cause serious human harm injury or death if inhaled, swallowed or allowed to come into contact with the skin. Examples include biomedical waste, tear gas, dye, acids, cyanides, arsenic, and biological cultures. 

Radioactive Material: Class Seven 

As perhaps the most notorious type of hazardous waste, radioactive material is the most well known. Any substance in this class will emit ionizing radiation, which is highly dangerous to all living creatures. 

Corrosives: Class Eight 

If a material can cause another to disintegrate, it falls under class eight. Batteries, dyes, paints, acid solutions, and acids all fall into this category. 

Miscellaneous Hazardous Materials: Class Nine 

Last but not least, class nine is reserved for all other materials that are still dangerous but don’t fit into the other eight sections. It can include dry ice, lithium ion batteries, first-aid kits, fuel cell engines and more. 


No matter what kind of environmental issue you may have, AEG Environmental can help. We handle every situation with care, dedication, and a commitment to exemplary customer service. When you have an emergency, you can rely on us! Need training? We can handle that too! We train in a wide variety of environmental management areas so that your company can remain compliant with EPA, DOT, and OSHA. Make sure to check out our blog for the latest and greatest in the waste management world! You should also follow us on social media for updates.

This entry was posted on Tuesday, August 27th, 2019 at 3:38 pm. Both comments and pings are currently closed.

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