What do vertical stripes on a placard typically indicate?

Vertical stripes on a placard typically signify that the material being transported is classified as radioactive. The use of striped patterns, often with a specific color coding, is part of the standardized system to communicate hazards associated with the transport of dangerous goods. In this instance, the stripes help first responders identify the presence of radioactive materials instantly, which is critical for ensuring safety during any potential incident involving such substances.

For items related to gases, explosives, or flammable materials, different symbols, colors, and patterns are utilized. For example, explosive materials often have orange or yellow backgrounds, while flammable materials are typically indicated by red. Therefore, the characteristic of vertical stripes specifically correlates with the danger posed by radioactive materials, assisting in the appropriate and prompt response by emergency personnel.