What is a sign called that warns that hazardous material is present in a vehicle or container?

A placard is a sign that is used to indicate the presence of hazardous materials in a vehicle or container. It serves a critical safety function by alerting individuals to the potential risks associated with the materials being transported. Placards are designed to be highly visible and adhere to standardized formats and colors, which correlate with the type of hazard present, such as flammable materials, explosives, or toxic substances. This ensures that emergency responders, operators, and the general public can quickly identify the nature of the hazards and take appropriate safety precautions.

In contrast, labels are typically smaller and used to provide specific information about the contents of a package rather than conveying overall hazard information for transport vehicles. A bill of lading is a shipping document that outlines the details of the shipment, including the type and quantity of goods being transported, but it does not serve as a warning sign. An identification tag may be used for various purposes, such as tracking or identifying items, but it does not specifically indicate hazardous materials in a transport context.