Placard

A placard is a notice installed in a public place, like a small , sign, or . It can be attached to or hung from a vehicle or building to indicate information about the vehicle operator or contents of a vehicle or building. It can also refer to paperboard signs or notice carried by picketers or demonstrators.

A placard is placed on a building to indicate special information about that building. The most common placard which had been used is the fallout shelter black and yellow trefoil indicating that a building was specifically prepared for use for emergency shelter in the event of a nuclear explosion in the area of the particular building. Temporary placards may be placed on buildings such as warning signs over tenting to indicate the building is being fumigated and that no one should enter.

In some locations it is common practice, and in some areas (such as California) it is required by law that any primary entrance to a commercial building have a placard attached above the entrance door(s) reading "This door to remain unlocked during business hours."

The two most common placards in general use on vehicles are disabled parking permits for personal automobiles, and hazardous materials (hazmats) warning signs for commercial vehicles. There are other types, such as the "wide load" signs used when mobile homes are transported by road.

Commercial vehicle placards are of two general types, the single indicator, where in specific information of a fixed nature is displayed by the sign, such as the yellow "oxidizing agent" sign below, and the NFPA "fire diamond" style device which can be changed to depict new information as the contents of the vehicle change, and which carries information about the compound being carried, placard is similar to posters and logos, its flammability and resistance to water, for example. To see the signs put on trucks and trains meaning hazmats see: Hazmat Placards.

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