Final answer:
The DOT requires vehicles transporting hazardous materials to display placards describing the class of hazardous materials. Hazard diamonds on chemical containers summarize major hazards of a substance. Characteristic hazardous wastes are toxic, corrosive, flammable, or reactive materials.
Step-by-step explanation:
In the United States, the Department of Transportation (DOT) requires most vehicles transporting hazardous materials to display placards that describe the class of hazardous materials on board. These placards provide valuable information about the dangers associated with specific substances, allowing people to be aware and take necessary precautions.
The hazard diamond, often seen on chemical containers, is one such placard that summarizes major hazards of a chemical substance.
Characteristic hazardous wastes, as classified by the US Environmental Agency (EPA), are materials that are toxic, corrosive, flammable, or reactive. It is important to handle these wastes properly to ensure safety. The hazardous waste regulations and transportation rules apply to generators and transporters who move regulated wastes on public roads, highways, rails, and waterways.
For more information, you can refer to the US EPA's hazardous waste regulations and the NFPA hazard diamond.