Placards serve as an easily identifiable, visual source of information used by millions of workers in the transportation, public safety, and hazmat industries. Placards are diamond-shaped and when required, they must be placed on both ends and both sides of trucks, railcars, and intermodal containers that carry hazardous materials. They are coded by color and contain symbols and numbers that designate the hazard class or division of the hazardous material that is being shipped. or bulk and certain non-bulk shipments, a four digit hazardous material identification number may be on the placard or on an accompanying orange panel or a white square sign.

Placards are a key component of an international system of hazard communication to assist in identifying the general type of hazard associated with hazardous materials to quickly understand the type of hazard the material poses to safety. They help regulators working in compliance and enforcement ensure that hazardous materials shipments are transported in a safe manner consistent with the regulations, help transportation workers identify hazmat shipments so that they can be handled appropriately, and help emergency responders quickly ascertain the nature of the hazard that they face in the case of an accident or spill.

Look for the following symbols in your community and be sure to act cautiously when traveling near or encountering packages or containers possessing these signs.