What is the primary purpose of placards and labels in hazmat transportation?

The primary purpose of placards and labels in hazardous materials (hazmat) transportation is to communicate critical safety information about the materials being transported to emergency responders and the public. The correct answer focuses on the identification of hazardous materials, including their associated risks.

By identifying the worst hazmat, placards and labels serve to alert those who may encounter the transport vehicle, including law enforcement and emergency services personnel, to the potential dangers involved. These visual markers help ensure that proper precautions are taken in the event of an accident or spill, enabling responders to effectively manage the situation based on the specific type of hazard present.

Other choices provided, such as decorative elements, weight classification, and expiration dates, do not align with the primary purpose of effective hazard communication in the context of transportation and safety protocols. Placards and labels are strictly functional and are crucial in ensuring safe transportation practices in the handling of hazardous materials.